Memory barriers are useful to ensure memory accesses from one CPU appear in
the original order as seen by other CPUs.
Some smp_rmb() and smp_wmb() are used, but they are not ordering multiple
memory accesses.
Remove them.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250626151940.1756398-1-namcao@linutronix.de
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
ftrace has two flavors:
1) static: Where every function always calls the ftrace trampoline
2) dynamic: Where each function has nops that can be changed on demand to
jump to the ftrace trampoline when needed.
The static flavor has very high performance overhead and was only created
to make it easier for architectures to implement the dynamic flavor. An
architecture developer can first implement the static ftrace to make sure
the trampolines work before working on the more complicated dynamic aspect
of ftrace. Once the architecture can support dynamic ftrace, there's no
reason to continue to support the static flavor. In fact, the static
flavor tends to bitrot and bugs start to appear in them.
Remove the prompt to pick DYNAMIC_FTRACE and simply enable it if the
architecture supports it.
Link: https://lore.kernel.org/all/f7e12c6d-892e-4ca3-9ef0-fbb524d04a48@ghiti.fr/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: ChenMiao <chenmiao.ku@gmail.com>
Link: https://lore.kernel.org/20250703115222.2d7c8cd5@batman.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a warning if unregister_ftrace_graph() is called without ever
registering it, or if register_ftrace_graph() is called twice. This can
detect errors when they happen and not later when there's a side effect:
Link: https://lore.kernel.org/all/20250617120830.24fbdd62@gandalf.local.home/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/20250701194451.22e34724@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the ring buffer was first introduced, reading the non-consuming
"trace" file required disabling the writing of the ring buffer. To make
sure the writing was fully disabled before iterating the buffer with a
non-consuming read, it would set the disable flag of the buffer and then
call an RCU synchronization to make sure all the buffers were
synchronized.
The function ring_buffer_read_start() originally would initialize the
iterator and call an RCU synchronization, but this was for each individual
per CPU buffer where this would get called many times on a machine with
many CPUs before the trace file could be read. The commit 72c9ddfd4c
("ring-buffer: Make non-consuming read less expensive with lots of cpus.")
separated ring_buffer_read_start into ring_buffer_read_prepare(),
ring_buffer_read_sync() and then ring_buffer_read_start() to allow each of
the per CPU buffers to be prepared, call the read_buffer_read_sync() once,
and then the ring_buffer_read_start() for each of the CPUs which made
things much faster.
The commit 1039221cc2 ("ring-buffer: Do not disable recording when there
is an iterator") removed the requirement of disabling the recording of the
ring buffer in order to iterate it, but it did not remove the
synchronization that was happening that was required to wait for all the
buffers to have no more writers. It's now OK for the buffers to have
writers and no synchronization is needed.
Remove the synchronization and put back the interface for the ring buffer
iterator back before commit 72c9ddfd4c was applied.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250630180440.3eabb514@batman.local.home
Reported-by: David Howells <dhowells@redhat.com>
Fixes: 1039221cc2 ("ring-buffer: Do not disable recording when there is an iterator")
Tested-by: David Howells <dhowells@redhat.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
As the trace event powernv_throttle is only used by the powernv code, move
it to a separate include file and have that code directly enable it.
Trace events can take up around 5K of memory when they are defined
regardless if they are used or not. It wastes memory to have them defined
in configurations where the tracepoint is not used.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/20250612145407.906308844@goodmis.org
Fixes: 0306e481d4 ("cpufreq: powernv/tracing: Add powernv_throttle tracepoint")
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Fix timerlat with use of FORTIFY_SOURCE
FORTIFY_SOURCE was added to the stack tracer where it compares the
entry->caller array to having entry->size elements.
timerlat has the following:
memcpy(&entry->caller, fstack->calls, size);
entry->size = size;
Which triggers FORTIFY_SOURCE as the caller is populated before the
entry->size is initialized.
Swap the order to satisfy FORTIFY_SOURCE logic.
- Add down_write(trace_event_sem) when adding trace events in modules
Trace events being added to the ftrace_events array are protected by
the trace_event_sem semaphore. But when loading modules that have
trace events, the addition of the events are not protected by the
semaphore and loading two modules that have events at the same time
can corrupt the list.
Also add a lockdep_assert_held(trace_event_sem) to
_trace_add_event_dirs() to confirm its held when iterating the list.
-----BEGIN PGP SIGNATURE-----
iIoEABYKADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCaH06gBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qoJsAP0a+/E0f+5g7O/OtYPVEDSCREv1vj9c
3dr0iWopqaOC7gEAw8Vc5iWIHKcB/JuJ+GqALoutL+lihruG26MWkFFsOgU=
=zH5J
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.16-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix timerlat with use of FORTIFY_SOURCE
FORTIFY_SOURCE was added to the stack tracer where it compares the
entry->caller array to having entry->size elements.
timerlat has the following:
memcpy(&entry->caller, fstack->calls, size);
entry->size = size;
Which triggers FORTIFY_SOURCE as the caller is populated before the
entry->size is initialized.
Swap the order to satisfy FORTIFY_SOURCE logic.
- Add down_write(trace_event_sem) when adding trace events in modules
Trace events being added to the ftrace_events array are protected by
the trace_event_sem semaphore. But when loading modules that have
trace events, the addition of the events are not protected by the
semaphore and loading two modules that have events at the same time
can corrupt the list.
Also add a lockdep_assert_held(trace_event_sem) to
_trace_add_event_dirs() to confirm it is held when iterating the
list.
* tag 'trace-v6.16-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Add down_write(trace_event_sem) when adding trace event
tracing/osnoise: Fix crash in timerlat_dump_stack()
When a module is loaded, it adds trace events defined by the module. It
may also need to modify the modules trace printk formats to replace enum
names with their values.
If two modules are loaded at the same time, the adding of the event to the
ftrace_events list can corrupt the walking of the list in the code that is
modifying the printk format strings and crash the kernel.
The addition of the event should take the trace_event_sem for write while
it adds the new event.
Also add a lockdep_assert_held() on that semaphore in
__trace_add_event_dirs() as it iterates the list.
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://lore.kernel.org/20250718223158.799bfc0c@batman.local.home
Reported-by: Fusheng Huang(黄富生) <Fusheng.Huang@luxshare-ict.com>
Closes: https://lore.kernel.org/all/20250717105007.46ccd18f@batman.local.home/
Fixes: 110bf2b764 ("tracing: add protection around module events unload")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
We have observed kernel panics when using timerlat with stack saving,
with the following dmesg output:
memcpy: detected buffer overflow: 88 byte write of buffer size 0
WARNING: CPU: 2 PID: 8153 at lib/string_helpers.c:1032 __fortify_report+0x55/0xa0
CPU: 2 UID: 0 PID: 8153 Comm: timerlatu/2 Kdump: loaded Not tainted 6.15.3-200.fc42.x86_64 #1 PREEMPT(lazy)
Call Trace:
<TASK>
? trace_buffer_lock_reserve+0x2a/0x60
__fortify_panic+0xd/0xf
__timerlat_dump_stack.cold+0xd/0xd
timerlat_dump_stack.part.0+0x47/0x80
timerlat_fd_read+0x36d/0x390
vfs_read+0xe2/0x390
? syscall_exit_to_user_mode+0x1d5/0x210
ksys_read+0x73/0xe0
do_syscall_64+0x7b/0x160
? exc_page_fault+0x7e/0x1a0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
__timerlat_dump_stack() constructs the ftrace stack entry like this:
struct stack_entry *entry;
...
memcpy(&entry->caller, fstack->calls, size);
entry->size = fstack->nr_entries;
Since commit e7186af7fb ("tracing: Add back FORTIFY_SOURCE logic to
kernel_stack event structure"), struct stack_entry marks its caller
field with __counted_by(size). At the time of the memcpy, entry->size
contains garbage from the ringbuffer, which under some circumstances is
zero, triggering a kernel panic by buffer overflow.
Populate the size field before the memcpy so that the out-of-bounds
check knows the correct size. This is analogous to
__ftrace_trace_stack().
Cc: stable@vger.kernel.org
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Attila Fazekas <afazekas@redhat.com>
Link: https://lore.kernel.org/20250716143601.7313-1-tglozar@redhat.com
Fixes: e7186af7fb ("tracing: Add back FORTIFY_SOURCE logic to kernel_stack event structure")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
After a recent change in clang to strengthen uninitialized warnings [1],
it points out that in one of the error paths in parse_btf_arg(), params
is used uninitialized:
kernel/trace/trace_probe.c:660:19: warning: variable 'params' is uninitialized when used here [-Wuninitialized]
660 | return PTR_ERR(params);
| ^~~~~~
Match many other NO_BTF_ENTRY error cases and return -ENOENT, clearing
up the warning.
Link: https://lore.kernel.org/all/20250715-trace_probe-fix-const-uninit-warning-v1-1-98960f91dd04@kernel.org/
Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/2110
Fixes: d157d76944 ("tracing/probes: Support BTF field access from $retval")
Link: 2464313eef [1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Add zoned block commands to blk_fill_rwbs:
- ZONE APPEND will be decoded as 'ZA'
- ZONE RESET will be decoded as 'ZR'
- ZONE RESET ALL will be decoded as 'ZRA'
- ZONE FINISH will be decoded as 'ZF'
- ZONE OPEN will be decoded as 'ZO'
- ZONE CLOSE will be decoded as 'ZC'
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250715115324.53308-2-johannes.thumshirn@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Attach_type will be set when a link is created by user. It is better to
record attach_type in bpf_link generically and have it available
universally for all link types. So add the attach_type field in bpf_link
and move the sleepable field to avoid unnecessary gap padding.
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20250710032038.888700-2-chen.dylane@linux.dev
Replace internal subbuf_start in blktrace with the default policy in
relayfs.
Remove dropped field from struct blktrace. Correspondingly, call the
common helper in relay. By incrementing full_count to keep track of how
many times we encountered a full buffer issue, user space will know how
many events were lost.
Link: https://lkml.kernel.org/r/20250612061201.34272-5-kerneljasonxing@gmail.com
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Yushan Zhou <katrinzhou@tencent.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "relayfs: misc changes", v5.
The series mostly focuses on the error counters which helps every user
debug their own kernel module.
This patch (of 5):
prev_padding represents the unused space of certain subbuffer. If the
content of a call of relay_write() exceeds the limit of the remainder of
this subbuffer, it will skip storing in the rest space and record the
start point as buf->prev_padding in relay_switch_subbuf(). Since the buf
is a per-cpu big buffer, the point of prev_padding as a global value for
the whole buffer instead of a single subbuffer (whose padding info is
stored in buf->padding[]) seems meaningless from the real use cases, so we
don't bother to record it any more.
Link: https://lkml.kernel.org/r/20250612061201.34272-1-kerneljasonxing@gmail.com
Link: https://lkml.kernel.org/r/20250612061201.34272-2-kerneljasonxing@gmail.com
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Yushan Zhou <katrinzhou@tencent.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The comment above buffer mentions sign, 10 bytes width for number and null
terminator, but buffer itself isn't large enough to hold that much data.
This is a cosmetic change, since PID cannot be negative, other than -1.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Link: https://lore.kernel.org/20250617152110.2530-1-a.sadovnikov@ispras.ru
Signed-off-by: Artem Sadovnikov <a.sadovnikov@ispras.ru>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Rewind persistent ring buffer pages which have been read in the previous
boot. Those pages are highly possible to be lost before writing it to the
disk if the previous kernel crashed. In this case, the trace data is kept
on the persistent ring buffer, but it can not be read because its commit
size has been reset after read. This skips clearing the commit size of
each sub-buffer and recover it after reboot.
Note: If you read the previous boot data via trace_pipe, that is not
accessible in that time. But reboot without clearing (or reusing) the read
data, the read data is recovered again in the next boot.
Thus, when you read the previous boot data, clear it by `echo > trace`.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/174899582116.955054.773265393511190051.stgit@mhiramat.tok.corp.google.com
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Now that there are 2 monitors for real-time applications, users may want to
enable both of them simultaneously. Make the number of per-task monitor
configurable. Default it to 2 for now.
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/93e83313fc4ba7f6e66f4abe80ca5f5494d658d0.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a monitor for checking that real-time tasks do not go to sleep in a
manner that may cause undesirable latency.
Also change
RV depends on TRACING
to
RV select TRACING
to avoid the following recursive dependency:
error: recursive dependency detected!
symbol TRACING is selected by PREEMPTIRQ_TRACEPOINTS
symbol PREEMPTIRQ_TRACEPOINTS depends on TRACE_IRQFLAGS
symbol TRACE_IRQFLAGS is selected by RV_MON_SLEEP
symbol RV_MON_SLEEP depends on RV
symbol RV depends on TRACING
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/75bc5bcc741d153aa279c95faf778dff35c5c8ad.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Userspace real-time applications may have design flaws that they raise
page faults in real-time threads, and thus have unexpected latencies.
Add an linear temporal logic monitor to detect this scenario.
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/78fea8a2de6d058241d3c6502c1a92910772b0ed.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add the container "rtapp" which is the monitor collection for detecting
problems with real-time applications. The monitors will be added in the
follow-up commits.
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/fb18b87631d386271de00959d8d4826f23fcd1cd.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
While attempting to implement DA monitors for some complex specifications,
deterministic automaton is found to be inappropriate as the specification
language. The automaton is complicated, hard to understand, and
error-prone.
For these cases, linear temporal logic is more suitable as the
specification language.
Add support for linear temporal logic runtime verification monitor.
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/d366c1fed60ed4e8f6451f3c15a99755f2740b5f.1752088709.git.namcao@linutronix.de
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
CONFIG_DA_MON_EVENTS is not specific to deterministic automaton. It could
be used for other monitor types. Therefore rename it to
CONFIG_RV_MON_EVENTS.
This prepares for the introduction of linear temporal logic monitor.
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/507210517123d887c1d208aa2fd45ec69765d3f0.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Each RV monitor has one static buffer to send to the reactors. If multiple
errors are detected simultaneously, the one buffer could be overwritten.
Instead, leave it to the reactors to handle buffering.
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Without "#undef TRACE_INCLUDE_FILE", there could be a build error due to
TRACE_INCLUDE_FILE being redefined. Therefore add it.
Also fix a typo while at it.
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/f805e074581e927bb176c742c981fa7675b6ebe5.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
A CPU mask on the stack is broken for large values of CONFIG_NR_CPUS:
kernel/trace/preemptirq_delay_test.c: In function ‘preemptirq_delay_run’:
kernel/trace/preemptirq_delay_test.c:143:1: error: the frame size of 8512 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]
Fall back to dynamic allocation here.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Song Chen <chensong_2000@189.cn>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250620111215.3365305-1-arnd@kernel.org
Fixes: 4b9091e1c1 ("kernel: trace: preemptirq_delay_test: add cpu affinity")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Freeing of filters requires to wait for both an RCU grace period as well as
a RCU task trace wait period after they have been detached from their
lists. The trace task period can be quite large so the freeing of the
filters was moved to use the call_rcu*() routines. The problem with that is
that the callback functions of call_rcu*() is done from a soft irq and can
cause latencies if the callback takes a bit of time.
The filters are freed per event in a system and the syscalls system
contains an event per system call, which can be over 700 events. Freeing 700
filters in a bottom half is undesirable.
Instead, move the freeing to use queue_rcu_work() which is done in task
context.
Link: https://lore.kernel.org/all/9a2f0cd0-1561-4206-8966-f93ccd25927f@paulmck-laptop/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250609131732.04fd303b@gandalf.local.home
Fixes: a9d0aab5eb ("tracing: Fix regression of filter waiting a long time on RCU synchronization")
Suggested-by: "Paul E. McKenney" <paulmck@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The dedicated cpumask_next_wrap() is more verbose and effective than
cpumask_next() followed by cpumask_first().
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250605000651.45281-1-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Alexei suggested, 'link_type' can be more precise and differentiate
for human in fdinfo. In fact BPF_LINK_TYPE_KPROBE_MULTI includes
kretprobe_multi type, the same as BPF_LINK_TYPE_UPROBE_MULTI, so we
can show it more concretely.
link_type: kprobe_multi
link_id: 1
prog_tag: d2b307e915f0dd37
...
link_type: kretprobe_multi
link_id: 2
prog_tag: ab9ea0545870781d
...
link_type: uprobe_multi
link_id: 9
prog_tag: e729f789e34a8eca
...
link_type: uretprobe_multi
link_id: 10
prog_tag: 7db356c03e61a4d4
Co-developed-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Link: https://lore.kernel.org/r/20250702153958.639852-1-chen.dylane@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
As same as fprobe, register tracepoint stub function only when enabling
tprobe events. The major changes are introducing a list of
tracepoint_user and its lock, and tprobe_event_module_nb, which is
another module notifier for module loading/unloading. By spliting the
lock from event_mutex and a module notifier for trace_fprobe, it
solved AB-BA lock dependency issue between event_mutex and
tracepoint_module_list_mutex.
Link: https://lore.kernel.org/all/174343538901.843280.423773753642677941.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Currently fprobe events are registered when it is defined. Thus it will
give some overhead even if it is disabled. This changes it to register the
fprobe only when it is enabled.
Link: https://lore.kernel.org/all/174343537128.843280.16131300052837035043.stgit@devnote2/
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cleanup __store_entry_arg() so that it is easier to understand.
The main complexity may come from combining the loops for finding
stored-entry-arg and max-offset and appending new entry.
This split those different loops into 3 parts, lookup the same
entry-arg, find the max offset and append new entry.
Link: https://lore.kernel.org/all/174323039929.348535.4705349977127704120.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cross-merge BPF, perf and other fixes after downstream PRs.
It restores BPF CI to green after critical fix
commit bc4394e5e7 ("perf: Fix the throttle error of some clock events")
No conflicts.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The underlying lookup_user_key() function uses a signed 32 bit integer
for key serial numbers because legitimate serial numbers are positive
(and > 3) and keyrings are negative. Using a u32 for the keyring in
the bpf function doesn't currently cause any conversion problems but
will start to trip the signed to unsigned conversion warnings when the
kernel enables them, so convert the argument to signed (and update the
tests accordingly) before it acquires more users.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Link: https://lore.kernel.org/r/84cdb0775254d297d75e21f577089f64abdfbd28.camel@HansenPartnership.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The variable "head" is allocated and initialized as a list before
allocating the first "item" for the list. If the allocation of "item"
fails, it frees "head" and then jumps to the label "free_now" which will
process head and free it.
This will cause a UAF of "head", and it doesn't need to free it before
jumping to the "free_now" label as that code will free it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250610093348.33c5643a@gandalf.local.home
Fixes: a9d0aab5eb ("tracing: Fix regression of filter waiting a long time on RCU synchronization")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202506070424.lCiNreTI-lkp@intel.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Fix regression of waiting a long time on updating trace event filters
When the faultable trace points were added, it needed task trace RCU
synchronization. This was added to the tracepoint_synchronize_unregister()
function. The filter logic always called this function whenever it
updated the trace event filters before freeing the old filters.
This increased the time of "trace-cmd record" from taking 13 seconds
to running over 2 minutes to complete.
Move the freeing of the filters to call_rcu*() logic, which brings the
time back down to 13 seconds.
- Fix ring_buffer_subbuf_order_set() error path lock protection
The error path of the ring_buffer_subbuf_order_set() released the
mutex too early and allowed subsequent accesses to setting the
subbuffer size to corrupt the data and cause a bug.
By moving the mutex locking to the end of the error path, it prevents
the reentrant access to the critical data and also allows the function
to convert the taking of the mutex over to the guard() logic.
- Remove unused power management clock events
The clock events were added in 2010 for power management. In 2011
arm used them. In 2013 the code they were used in was removed.
These events have been wasting memory since then.
- Fix sparse warnings
There was a few places that sparse warned about trace_events_filter.c
where file->filter was referenced directly, but it is annotated with
an __rcu tag. Use the helper functions and fix them up to use
rcu_dereference() properly.
-----BEGIN PGP SIGNATURE-----
iIoEABYKADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCaEST0xQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qgdSAPoD7L17oeiP5KQkM0wPuPBz0tmJF7XE
2VmHp1lBu5rYwgEAyHTD7SqWvInMMp9sGt5tzkByXpOsYC65/RprkbFpXwA=
=s4wK
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull more tracing fixes from Steven Rostedt:
- Fix regression of waiting a long time on updating trace event filters
When the faultable trace points were added, it needed task trace RCU
synchronization.
This was added to the tracepoint_synchronize_unregister() function.
The filter logic always called this function whenever it updated the
trace event filters before freeing the old filters. This increased
the time of "trace-cmd record" from taking 13 seconds to running over
2 minutes to complete.
Move the freeing of the filters to call_rcu*() logic, which brings
the time back down to 13 seconds.
- Fix ring_buffer_subbuf_order_set() error path lock protection
The error path of the ring_buffer_subbuf_order_set() released the
mutex too early and allowed subsequent accesses to setting the
subbuffer size to corrupt the data and cause a bug.
By moving the mutex locking to the end of the error path, it prevents
the reentrant access to the critical data and also allows the
function to convert the taking of the mutex over to the guard()
logic.
- Remove unused power management clock events
The clock events were added in 2010 for power management. In 2011 arm
used them. In 2013 the code they were used in was removed. These
events have been wasting memory since then.
- Fix sparse warnings
There was a few places that sparse warned about trace_events_filter.c
where file->filter was referenced directly, but it is annotated with
an __rcu tag. Use the helper functions and fix them up to use
rcu_dereference() properly.
* tag 'trace-v6.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Add rcu annotation around file->filter accesses
tracing: PM: Remove unused clock events
ring-buffer: Fix buffer locking in ring_buffer_subbuf_order_set()
tracing: Fix regression of filter waiting a long time on RCU synchronization
Running sparse on trace_events_filter.c triggered several warnings about
file->filter being accessed directly even though it's annotated with __rcu.
Add rcu_dereference() around it and shuffle the logic slightly so that
it's always referenced via accessor functions.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250607102821.6c7effbf@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
* Support for the FWFT SBI extension, which is part of SBI 3.0 and a
dependency for many new SBI and ISA extensions.
* Support for getrandom() in the VDSO.
* Support for mseal.
* Optimized routines for raid6 syndrome and recovery calculations.
* kexec_file() supports loading Image-formatted kernel binaries.
* Improvements to the instruction patching framework to allow for atomic
instruction patching, along with rules as to how systems need to
behave in order to function correctly.
* Support for a handful of new ISA extensions: Svinval, Zicbop, Zabha,
some SiFive vendor extensions.
* Various fixes and cleanups, including: misaligned access handling, perf
symbol mangling, module loading, PUD THPs, and improved uaccess
routines.
-----BEGIN PGP SIGNATURE-----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=cZGy
-----END PGP SIGNATURE-----
Merge tag 'riscv-for-linus-6.16-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
- Support for the FWFT SBI extension, which is part of SBI 3.0 and a
dependency for many new SBI and ISA extensions
- Support for getrandom() in the VDSO
- Support for mseal
- Optimized routines for raid6 syndrome and recovery calculations
- kexec_file() supports loading Image-formatted kernel binaries
- Improvements to the instruction patching framework to allow for
atomic instruction patching, along with rules as to how systems need
to behave in order to function correctly
- Support for a handful of new ISA extensions: Svinval, Zicbop, Zabha,
some SiFive vendor extensions
- Various fixes and cleanups, including: misaligned access handling,
perf symbol mangling, module loading, PUD THPs, and improved uaccess
routines
* tag 'riscv-for-linus-6.16-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (69 commits)
riscv: uaccess: Only restore the CSR_STATUS SUM bit
RISC-V: vDSO: Wire up getrandom() vDSO implementation
riscv: enable mseal sysmap for RV64
raid6: Add RISC-V SIMD syndrome and recovery calculations
riscv: mm: Add support for Svinval extension
RISC-V: Documentation: Add enough title underlines to CMODX
riscv: Improve Kconfig help for RISCV_ISA_V_PREEMPTIVE
MAINTAINERS: Update Atish's email address
riscv: uaccess: do not do misaligned accesses in get/put_user()
riscv: process: use unsigned int instead of unsigned long for put_user()
riscv: make unsafe user copy routines use existing assembly routines
riscv: hwprobe: export Zabha extension
riscv: Make regs_irqs_disabled() more clear
perf symbols: Ignore mapping symbols on riscv
RISC-V: Kconfig: Fix help text of CMDLINE_EXTEND
riscv: module: Optimize PLT/GOT entry counting
riscv: Add support for PUD THP
riscv: xchg: Prefetch the destination word for sc.w
riscv: Add ARCH_HAS_PREFETCH[W] support with Zicbop
riscv: Add support for Zicbop
...
When faultable trace events were added, a trace event may no longer use
normal RCU to synchronize but instead used synchronize_rcu_tasks_trace().
This synchronization takes a much longer time to synchronize.
The filter logic would free the filters by calling
tracepoint_synchronize_unregister() after it unhooked the filter strings
and before freeing them. With this function now calling
synchronize_rcu_tasks_trace() this increased the time to free a filter
tremendously. On a PREEMPT_RT system, it was even more noticeable.
# time trace-cmd record -p function sleep 1
[..]
real 2m29.052s
user 0m0.244s
sys 0m20.136s
As trace-cmd would clear out all the filters before recording, it could
take up to 2 minutes to do a recording of "sleep 1".
To find out where the issues was:
~# trace-cmd sqlhist -e -n sched_stack select start.prev_state as state, end.next_comm as comm, TIMESTAMP_DELTA_USECS as delta, start.STACKTRACE as stack from sched_switch as start join sched_switch as end on start.prev_pid = end.next_pid
Which will produce the following commands (and -e will also execute them):
echo 's:sched_stack s64 state; char comm[16]; u64 delta; unsigned long stack[];' >> /sys/kernel/tracing/dynamic_events
echo 'hist:keys=prev_pid:__arg_18057_2=prev_state,__arg_18057_4=common_timestamp.usecs,__arg_18057_7=common_stacktrace' >> /sys/kernel/tracing/events/sched/sched_switch/trigger
echo 'hist:keys=next_pid:__state_18057_1=$__arg_18057_2,__comm_18057_3=next_comm,__delta_18057_5=common_timestamp.usecs-$__arg_18057_4,__stack_18057_6=$__arg_18057_7:onmatch(sched.sched_switch).trace(sched_stack,$__state_18057_1,$__comm_18057_3,$__delta_18057_5,$__stack_18057_6)' >> /sys/kernel/tracing/events/sched/sched_switch/trigger
The above creates a synthetic event that creates a stack trace when a task
schedules out and records it with the time it scheduled back in. Basically
the time a task is off the CPU. It also records the state of the task when
it left the CPU (running, blocked, sleeping, etc). It also saves the comm
of the task as "comm" (needed for the next command).
~# echo 'hist:keys=state,stack.stacktrace:vals=delta:sort=state,delta if comm == "trace-cmd" && state & 3' > /sys/kernel/tracing/events/synthetic/sched_stack/trigger
The above creates a histogram with buckets per state, per stack, and the
value of the total time it was off the CPU for that stack trace. It filters
on tasks with "comm == trace-cmd" and only the sleeping and blocked states
(1 - sleeping, 2 - blocked).
~# trace-cmd record -p function sleep 1
~# cat /sys/kernel/tracing/events/synthetic/sched_stack/hist | tail -18
{ state: 2, stack.stacktrace __schedule+0x1545/0x3700
schedule+0xe2/0x390
schedule_timeout+0x175/0x200
wait_for_completion_state+0x294/0x440
__wait_rcu_gp+0x247/0x4f0
synchronize_rcu_tasks_generic+0x151/0x230
apply_subsystem_event_filter+0xa2b/0x1300
subsystem_filter_write+0x67/0xc0
vfs_write+0x1e2/0xeb0
ksys_write+0xff/0x1d0
do_syscall_64+0x7b/0x420
entry_SYSCALL_64_after_hwframe+0x76/0x7e
} hitcount: 237 delta: 99756288 <<--------------- Delta is 99 seconds!
Totals:
Hits: 525
Entries: 21
Dropped: 0
This shows that this particular trace waited for 99 seconds on
synchronize_rcu_tasks() in apply_subsystem_event_filter().
In fact, there's a lot of places in the filter code that spends a lot of
time waiting for synchronize_rcu_tasks_trace() in order to free the
filters.
Add helper functions that will use call_rcu*() variants to asynchronously
free the filters. This brings the timings back to normal:
# time trace-cmd record -p function sleep 1
[..]
real 0m14.681s
user 0m0.335s
sys 0m28.616s
And the histogram also shows this:
~# cat /sys/kernel/tracing/events/synthetic/sched_stack/hist | tail -21
{ state: 2, stack.stacktrace __schedule+0x1545/0x3700
schedule+0xe2/0x390
schedule_timeout+0x175/0x200
wait_for_completion_state+0x294/0x440
__wait_rcu_gp+0x247/0x4f0
synchronize_rcu_normal+0x3db/0x5c0
tracing_reset_online_cpus+0x8f/0x1e0
tracing_open+0x335/0x440
do_dentry_open+0x4c6/0x17a0
vfs_open+0x82/0x360
path_openat+0x1a36/0x2990
do_filp_open+0x1c5/0x420
do_sys_openat2+0xed/0x180
__x64_sys_openat+0x108/0x1d0
do_syscall_64+0x7b/0x420
} hitcount: 2 delta: 77044
Totals:
Hits: 55
Entries: 28
Dropped: 0
Where the total waiting time of synchronize_rcu_tasks_trace() is 77
milliseconds.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Andreas Ziegler <ziegler.andreas@siemens.com>
Cc: Felix MOESSBAUER <felix.moessbauer@siemens.com>
Link: https://lore.kernel.org/20250606201936.1e3d09a9@batman.local.home
Reported-by: "Flot, Julien" <julien.flot@siemens.com>
Tested-by: Julien Flot <julien.flot@siemens.com>
Fixes: a363d27cdb ("tracing: Allow system call tracepoints to handle page faults")
Closes: https://lore.kernel.org/all/240017f656631c7dd4017aa93d91f41f653788ea.camel@siemens.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
riscv patches for 6.16-rc1, part 2
* Performance improvements
- Add support for vdso getrandom
- Implement raid6 calculations using vectors
- Introduce svinval tlb invalidation
* Cleanup
- A bunch of deduplication of the macros we use for manipulating instructions
* Misc
- Introduce a kunit test for kprobes
- Add support for mseal as riscv fits the requirements (thanks to Lorenzo for making sure of that :))
[Palmer: There was a rebase between part 1 and part 2, so I've had to do
some more git surgery here... at least two rounds of surgery...]
* alex-pr-2: (866 commits)
RISC-V: vDSO: Wire up getrandom() vDSO implementation
riscv: enable mseal sysmap for RV64
raid6: Add RISC-V SIMD syndrome and recovery calculations
riscv: mm: Add support for Svinval extension
riscv: Add kprobes KUnit test
riscv: kprobes: Remove duplication of RV_EXTRACT_ITYPE_IMM
riscv: kprobes: Remove duplication of RV_EXTRACT_UTYPE_IMM
riscv: kprobes: Remove duplication of RV_EXTRACT_RD_REG
riscv: kprobes: Remove duplication of RVC_EXTRACT_BTYPE_IMM
riscv: kprobes: Remove duplication of RVC_EXTRACT_C2_RS1_REG
riscv: kproves: Remove duplication of RVC_EXTRACT_JTYPE_IMM
riscv: kprobes: Remove duplication of RV_EXTRACT_BTYPE_IMM
riscv: kprobes: Remove duplication of RV_EXTRACT_RS1_REG
riscv: kprobes: Remove duplication of RV_EXTRACT_JTYPE_IMM
riscv: kprobes: Move branch_funct3 to insn.h
riscv: kprobes: Move branch_rs2_idx to insn.h
Linux 6.15-rc6
Input: xpad - fix xpad_device sorting
Input: xpad - add support for several more controllers
Input: xpad - fix Share button on Xbox One controllers
...
The following ftrace patch for riscv uses a data store to update ftrace
function. Therefore, a romote fence is required to order it against
function_trace_op updates. The mechanism is similar to the fence between
function_trace_op and update_ftrace_func in the generic ftrace, so we
leverage the same ftrace_sync_ipi function.
[ alex: Fix build warning when !CONFIG_DYNAMIC_FTRACE ]
Signed-off-by: Andy Chiu <andybnac@gmail.com>
Link: https://lore.kernel.org/r/20250407180838.42877-4-andybnac@gmail.com
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
If ftrace is disabled, it is meaningless to allocate a module map.
Add a check in allocate_ftrace_mod_map() to not allocate if ftrace is
disabled.
Link: https://lore.kernel.org/20250529111955.2349189-3-yebin@huaweicloud.com
Signed-off-by: Ye Bin <yebin10@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The following issue happens with a buggy module:
BUG: unable to handle page fault for address: ffffffffc05d0218
PGD 1bd66f067 P4D 1bd66f067 PUD 1bd671067 PMD 101808067 PTE 0
Oops: Oops: 0000 [#1] SMP KASAN PTI
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
RIP: 0010:sized_strscpy+0x81/0x2f0
RSP: 0018:ffff88812d76fa08 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffffc0601010 RCX: dffffc0000000000
RDX: 0000000000000038 RSI: dffffc0000000000 RDI: ffff88812608da2d
RBP: 8080808080808080 R08: ffff88812608da2d R09: ffff88812608da68
R10: ffff88812608d82d R11: ffff88812608d810 R12: 0000000000000038
R13: ffff88812608da2d R14: ffffffffc05d0218 R15: fefefefefefefeff
FS: 00007fef552de740(0000) GS:ffff8884251c7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffc05d0218 CR3: 00000001146f0000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ftrace_mod_get_kallsym+0x1ac/0x590
update_iter_mod+0x239/0x5b0
s_next+0x5b/0xa0
seq_read_iter+0x8c9/0x1070
seq_read+0x249/0x3b0
proc_reg_read+0x1b0/0x280
vfs_read+0x17f/0x920
ksys_read+0xf3/0x1c0
do_syscall_64+0x5f/0x2e0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The above issue may happen as follows:
(1) Add kprobe tracepoint;
(2) insmod test.ko;
(3) Module triggers ftrace disabled;
(4) rmmod test.ko;
(5) cat /proc/kallsyms; --> Will trigger UAF as test.ko already removed;
ftrace_mod_get_kallsym()
...
strscpy(module_name, mod_map->mod->name, MODULE_NAME_LEN);
...
The problem is when a module triggers an issue with ftrace and
sets ftrace_disable. The ftrace_disable is set when an anomaly is
discovered and to prevent any more damage, ftrace stops all text
modification. The issue that happened was that the ftrace_disable stops
more than just the text modification.
When a module is loaded, its init functions can also be traced. Because
kallsyms deletes the init functions after a module has loaded, ftrace
saves them when the module is loaded and function tracing is enabled. This
allows the output of the function trace to show the init function names
instead of just their raw memory addresses.
When a module is removed, ftrace_release_mod() is called, and if
ftrace_disable is set, it just returns without doing anything more. The
problem here is that it leaves the mod_list still around and if kallsyms
is called, it will call into this code and access the module memory that
has already been freed as it will return:
strscpy(module_name, mod_map->mod->name, MODULE_NAME_LEN);
Where the "mod" no longer exists and triggers a UAF bug.
Link: https://lore.kernel.org/all/20250523135452.626d8dcd@gandalf.local.home/
Cc: stable@vger.kernel.org
Fixes: aba4b5c22c ("ftrace: Save module init functions kallsyms symbols for tracing")
Link: https://lore.kernel.org/20250529111955.2349189-2-yebin@huaweicloud.com
Signed-off-by: Ye Bin <yebin10@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Allow the persistent ring buffer to be memory mapped
In the last merge window there was issues with the implementation of
mapping the persistent ring buffer because it was assumed that the
persistent memory was just physical memory without being part of the
kernel virtual address space. But this was incorrect and the persistent
ring buffer can be mapped the same way as the allocated ring buffer is
mapped.
The meta data for the persistent ring buffer is different than the normal
ring buffer and the organization of mapping it to user space is a little
different. Make the updates needed to the meta data to allow the
persistent ring buffer to be mapped to user space.
- Fix cpus_read_lock() with buffer->mutex and cpu_buffer->mapping_lock
Mapping the ring buffer to user space uses the cpu_buffer->mapping_lock.
The buffer->mutex can be taken when the mapping_lock is held, giving the
locking order of: cpu_buffer->mapping_lock -->> buffer->mutex. But there
also exists the ordering:
buffer->mutex -->> cpus_read_lock()
mm->mmap_lock -->> cpu_buffer->mapping_lock
cpus_read_lock() -->> mm->mmap_lock
causing a circular chain of:
cpu_buffer->mapping_lock -> buffer->mutex -->> cpus_read_lock() -->>
mm->mmap_lock -->> cpu_buffer->mapping_lock
By moving the cpus_read_lock() outside the buffer->mutex where:
cpus_read_lock() -->> buffer->mutex, breaks the deadlock chain.
- Do not trigger WARN_ON() for commit overrun
When the ring buffer is user space mapped and there's a "commit overrun"
(where an interrupt preempted an event, and then added so many events it
filled the buffer having to drop events when it hit the preempted event)
a WARN_ON() was triggered if this was read via a memory mapped buffer.
This is due to "missed events" being non zero when the reader page ended
up with the commit page. The idea was, if the writer is on the reader page,
there's only one page that has been written to and there should be no
missed events. But if a commit overrun is done where the writer is off the
commit page and looped around to the commit page causing missed events, it
is possible that the reader page is the commit page with missed events.
Instead of triggering a WARN_ON() when the reader page is the commit page
with missed events, trigger it when the reader page is the tail_page with
missed events. That's because the writer is always on the tail_page if
an event was interrupted (which holds the commit event) and continues off
the commit page.
- Reset the persistent buffer if it is fully consumed
On boot up, if the user fully consumes the last boot buffer of the
persistent buffer, if it reboots without enabling it, there will still be
events in the buffer which can cause confusion. Instead, reset the buffer
when it is fully consumed, so that the data is not read again.
- Clean up some goto out jumps
There's a few cases that the code jumps to the "out:" label that simply
returns a value. There used to be more work done at those labels but now
that they simply return a value use a return instead of jumping to a
label.
- Use guard() to simplify some of the code
Add guard() around some locking instead of jumping to a label to do the
unlocking.
- Use free() to simplify some of the code
Use free(kfree) on variables that will get freed on error and use
return_ptr() to return the variable when its not freed. There's one
instance where free(kfree) simplifies the code on a temp variable that was
allocated just for the function use.
-----BEGIN PGP SIGNATURE-----
iIoEABYKADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCaDjJMxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qkDzAP468AZOnjIxezfzYEmtcDl8ZUgf2U3I
XtXjn7aKH/gZiwD/dCCZX2IY2gddqAb6s9Bo4/AWgtYbjacLPL+pWYbTJwQ=
=DOfF
-----END PGP SIGNATURE-----
Merge tag 'trace-ringbuffer-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ring-buffer updates from Steven Rostedt:
- Allow the persistent ring buffer to be memory mapped
In the last merge window there was issues with the implementation of
mapping the persistent ring buffer because it was assumed that the
persistent memory was just physical memory without being part of the
kernel virtual address space. But this was incorrect and the
persistent ring buffer can be mapped the same way as the allocated
ring buffer is mapped.
The metadata for the persistent ring buffer is different than the
normal ring buffer and the organization of mapping it to user space
is a little different. Make the updates needed to the meta data to
allow the persistent ring buffer to be mapped to user space.
- Fix cpus_read_lock() with buffer->mutex and cpu_buffer->mapping_lock
Mapping the ring buffer to user space uses the
cpu_buffer->mapping_lock. The buffer->mutex can be taken when the
mapping_lock is held, giving the locking order of:
cpu_buffer->mapping_lock -->> buffer->mutex. But there also exists
the ordering:
buffer->mutex -->> cpus_read_lock()
mm->mmap_lock -->> cpu_buffer->mapping_lock
cpus_read_lock() -->> mm->mmap_lock
causing a circular chain of:
cpu_buffer->mapping_lock -> buffer->mutex -->> cpus_read_lock() -->>
mm->mmap_lock -->> cpu_buffer->mapping_lock
By moving the cpus_read_lock() outside the buffer->mutex where:
cpus_read_lock() -->> buffer->mutex, breaks the deadlock chain.
- Do not trigger WARN_ON() for commit overrun
When the ring buffer is user space mapped and there's a "commit
overrun" (where an interrupt preempted an event, and then added so
many events it filled the buffer having to drop events when it hit
the preempted event) a WARN_ON() was triggered if this was read via a
memory mapped buffer.
This is due to "missed events" being non zero when the reader page
ended up with the commit page. The idea was, if the writer is on the
reader page, there's only one page that has been written to and there
should be no missed events.
But if a commit overrun is done where the writer is off the commit
page and looped around to the commit page causing missed events, it
is possible that the reader page is the commit page with missed
events.
Instead of triggering a WARN_ON() when the reader page is the commit
page with missed events, trigger it when the reader page is the
tail_page with missed events. That's because the writer is always on
the tail_page if an event was interrupted (which holds the commit
event) and continues off the commit page.
- Reset the persistent buffer if it is fully consumed
On boot up, if the user fully consumes the last boot buffer of the
persistent buffer, if it reboots without enabling it, there will
still be events in the buffer which can cause confusion. Instead,
reset the buffer when it is fully consumed, so that the data is not
read again.
- Clean up some goto out jumps
There's a few cases that the code jumps to the "out:" label that
simply returns a value. There used to be more work done at those
labels but now that they simply return a value use a return instead
of jumping to a label.
- Use guard() to simplify some of the code
Add guard() around some locking instead of jumping to a label to do
the unlocking.
- Use free() to simplify some of the code
Use free(kfree) on variables that will get freed on error and use
return_ptr() to return the variable when its not freed. There's one
instance where free(kfree) simplifies the code on a temp variable
that was allocated just for the function use.
* tag 'trace-ringbuffer-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Simplify functions with __free(kfree) to free allocations
ring-buffer: Make ring_buffer_{un}map() simpler with guard(mutex)
ring-buffer: Simplify ring_buffer_read_page() with guard()
ring-buffer: Simplify reset_disabled_cpu_buffer() with use of guard()
ring-buffer: Remove jump to out label in ring_buffer_swap_cpu()
ring-buffer: Removed unnecessary if() goto out where out is the next line
tracing: Reset last-boot buffers when reading out all cpu buffers
ring-buffer: Allow reserve_mem persistent ring buffers to be mmapped
ring-buffer: Do not trigger WARN_ON() due to a commit_overrun
ring-buffer: Move cpus_read_lock() outside of buffer->mutex
Calling conventions of ->d_automount() made saner (flagday change)
vfs_submount() is gone - its sole remaining user (trace_automount) had
been switched to saner primitives.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCaDoRWQAKCRBZ7Krx/gZQ
6wxMAQCzuMc2GiGBMXzeK4SGA7d5rsK71unf+zczOd8NvbTImQEAs1Cu3u3bF3pq
EmHQWFTKBpBf+RHsLSoDHwUA+9THowM=
=GXLi
-----END PGP SIGNATURE-----
Merge tag 'pull-automount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull automount updates from Al Viro:
"Automount wart removal
A bunch of odd boilerplate gone from instances - the reason for
those was the need to protect the yet-to-be-attched mount from
mark_mounts_for_expiry() deciding to take it out.
But that's easy to detect and take care of in mark_mounts_for_expiry()
itself; no need to have every instance simulate mount being busy by
grabbing an extra reference to it, with finish_automount() undoing
that once it attaches that mount.
Should've done it that way from the very beginning... This is a
flagday change, thankfully there are very few instances.
vfs_submount() is gone - its sole remaining user (trace_automount)
had been switched to saner primitives"
* tag 'pull-automount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
kill vfs_submount()
saner calling conventions for ->d_automount()
- Have module addresses get updated in the persistent ring buffer
The addresses of the modules from the previous boot are saved in the
persistent ring buffer. If the same modules are loaded and an address is
in the old buffer points to an address that was both saved in the
persistent ring buffer and is loaded in memory, shift the address to point
to the address that is loaded in memory in the trace event.
- Print function names for irqs off and preempt off callsites
When ignoring the print fmt of a trace event and just printing the fields
directly, have the fields for preempt off and irqs off events still show
the function name (via kallsyms) instead of just showing the raw address.
- Clean ups of the histogram code
The histogram functions saved over 800 bytes on the stack to process
events as they come in. Instead, create per-cpu buffers that can hold this
information and have a separate location for each context level (thread,
softirq, IRQ and NMI).
Also add some more comments to the code.
- Add "common_comm" field for histograms
Add "common_comm" that uses the current->comm as a field in an event
histogram and acts like any of the other fields of the event.
- Show "subops" in the enabled_functions file
When the function graph infrastructure is used, a subsystem has a "subops"
that it attaches its callback function to. Instead of the
enabled_functions just showing a function calling the function that calls
the subops functions, also show the subops functions that will get called
for that function too.
- Add "copy_trace_marker" option to instances
There are cases where an instance is created for tooling to write into,
but the old tooling has the top level instance hardcoded into the
application. New tools want to consume the data from an instance and not
the top level buffer. By adding a copy_trace_marker option, whenever the
top instance trace_marker is written into, a copy of it is also written
into the instance with this option set. This allows new tools to read what
old tools are writing into the top buffer.
If this option is cleared by the top instance, then what is written into
the trace_marker is not written into the top instance. This is a way to
redirect the trace_marker writes into another instance.
- Have tracepoints created by DECLARE_TRACE() use trace_<name>_tp()
If a tracepoint is created by DECLARE_TRACE() instead of TRACE_EVENT(),
then it will not be exposed via tracefs. Currently there's no way to
differentiate in the kernel the tracepoint functions between those that
are exposed via tracefs or not. A calling convention has been made
manually to append a "_tp" prefix for events created by DECLARE_TRACE().
Instead of doing this manually, force it so that all DECLARE_TRACE()
events have this notation.
- Use __string() for task->comm in some sched events
Instead of hardcoding the comm to be TASK_COMM_LEN in some of the
scheduler events use __string() which makes it dynamic. Note, if these
events are parsed by user space it they may break, and the event may have
to be converted back to the hardcoded size.
- Have function graph "depth" be unsigned to the user
Internally to the kernel, the "depth" field of the function graph event is
signed due to -1 being used for end of boundary. What actually gets
recorded in the event itself is zero or positive. Reflect this to user
space by showing "depth" as unsigned int and be consistent across all
events.
- Allow an arbitrary long CPU string to osnoise_cpus_write()
The filtering of which CPUs to write to can exceed 256 bytes. If a machine
has 256 CPUs, and the filter is to filter every other CPU, the write would
take a string larger than 256 bytes. Instead of using a fixed size buffer
on the stack that is 256 bytes, allocate it to handle what is passed in.
- Stop having ftrace check the per-cpu data "disabled" flag
The "disabled" flag in the data structure passed to most ftrace functions
is checked to know if tracing has been disabled or not. This flag was
added back in 2008 before the ring buffer had its own way to disable
tracing. The "disable" flag is now not always set when needed, and the
ring buffer flag should be used in all locations where the disabled is
needed. Since the "disable" flag is redundant and incorrect, stop using it.
Fix up some locations that use the "disable" flag to use the ring buffer
info.
- Use a new tracer_tracing_disable/enable() instead of data->disable flag
There's a few cases that set the data->disable flag to stop tracing, but
this flag is not consistently used. It is also an on/off switch where if a
function set it and calls another function that sets it, the called
function may incorrectly enable it.
Use a new trace_tracing_disable() and tracer_tracing_enable() that uses a
counter and can be nested. These use the ring buffer flags which are
always checked making the disabling more consistent.
- Save the trace clock in the persistent ring buffer
Save what clock was used for tracing in the persistent ring buffer and set
it back to that clock after a reboot.
- Remove unused reference to a per CPU data pointer in mmiotrace functions
- Remove unused buffer_page field from trace_array_cpu structure
- Remove more strncpy() instances
- Other minor clean ups and fixes
-----BEGIN PGP SIGNATURE-----
iIoEABYKADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCaDhiqRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qkheAQDpyRHoXF1AIoEqyahDax8f3vpZQeCH
B/mn+YJmU1wuVgEA7AFALov5SHKv4IzoARz68GXtR0jGhP5D8uebUhUqDAQ=
=WmFG
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing updates from Steven Rostedt:
- Have module addresses get updated in the persistent ring buffer
The addresses of the modules from the previous boot are saved in the
persistent ring buffer. If the same modules are loaded and an address
is in the old buffer points to an address that was both saved in the
persistent ring buffer and is loaded in memory, shift the address to
point to the address that is loaded in memory in the trace event.
- Print function names for irqs off and preempt off callsites
When ignoring the print fmt of a trace event and just printing the
fields directly, have the fields for preempt off and irqs off events
still show the function name (via kallsyms) instead of just showing
the raw address.
- Clean ups of the histogram code
The histogram functions saved over 800 bytes on the stack to process
events as they come in. Instead, create per-cpu buffers that can hold
this information and have a separate location for each context level
(thread, softirq, IRQ and NMI).
Also add some more comments to the code.
- Add "common_comm" field for histograms
Add "common_comm" that uses the current->comm as a field in an event
histogram and acts like any of the other fields of the event.
- Show "subops" in the enabled_functions file
When the function graph infrastructure is used, a subsystem has a
"subops" that it attaches its callback function to. Instead of the
enabled_functions just showing a function calling the function that
calls the subops functions, also show the subops functions that will
get called for that function too.
- Add "copy_trace_marker" option to instances
There are cases where an instance is created for tooling to write
into, but the old tooling has the top level instance hardcoded into
the application. New tools want to consume the data from an instance
and not the top level buffer. By adding a copy_trace_marker option,
whenever the top instance trace_marker is written into, a copy of it
is also written into the instance with this option set. This allows
new tools to read what old tools are writing into the top buffer.
If this option is cleared by the top instance, then what is written
into the trace_marker is not written into the top instance. This is a
way to redirect the trace_marker writes into another instance.
- Have tracepoints created by DECLARE_TRACE() use trace_<name>_tp()
If a tracepoint is created by DECLARE_TRACE() instead of
TRACE_EVENT(), then it will not be exposed via tracefs. Currently
there's no way to differentiate in the kernel the tracepoint
functions between those that are exposed via tracefs or not. A
calling convention has been made manually to append a "_tp" prefix
for events created by DECLARE_TRACE(). Instead of doing this
manually, force it so that all DECLARE_TRACE() events have this
notation.
- Use __string() for task->comm in some sched events
Instead of hardcoding the comm to be TASK_COMM_LEN in some of the
scheduler events use __string() which makes it dynamic. Note, if
these events are parsed by user space it they may break, and the
event may have to be converted back to the hardcoded size.
- Have function graph "depth" be unsigned to the user
Internally to the kernel, the "depth" field of the function graph
event is signed due to -1 being used for end of boundary. What
actually gets recorded in the event itself is zero or positive.
Reflect this to user space by showing "depth" as unsigned int and be
consistent across all events.
- Allow an arbitrary long CPU string to osnoise_cpus_write()
The filtering of which CPUs to write to can exceed 256 bytes. If a
machine has 256 CPUs, and the filter is to filter every other CPU,
the write would take a string larger than 256 bytes. Instead of using
a fixed size buffer on the stack that is 256 bytes, allocate it to
handle what is passed in.
- Stop having ftrace check the per-cpu data "disabled" flag
The "disabled" flag in the data structure passed to most ftrace
functions is checked to know if tracing has been disabled or not.
This flag was added back in 2008 before the ring buffer had its own
way to disable tracing. The "disable" flag is now not always set when
needed, and the ring buffer flag should be used in all locations
where the disabled is needed. Since the "disable" flag is redundant
and incorrect, stop using it. Fix up some locations that use the
"disable" flag to use the ring buffer info.
- Use a new tracer_tracing_disable/enable() instead of data->disable
flag
There's a few cases that set the data->disable flag to stop tracing,
but this flag is not consistently used. It is also an on/off switch
where if a function set it and calls another function that sets it,
the called function may incorrectly enable it.
Use a new trace_tracing_disable() and tracer_tracing_enable() that
uses a counter and can be nested. These use the ring buffer flags
which are always checked making the disabling more consistent.
- Save the trace clock in the persistent ring buffer
Save what clock was used for tracing in the persistent ring buffer
and set it back to that clock after a reboot.
- Remove unused reference to a per CPU data pointer in mmiotrace
functions
- Remove unused buffer_page field from trace_array_cpu structure
- Remove more strncpy() instances
- Other minor clean ups and fixes
* tag 'trace-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (36 commits)
tracing: Fix compilation warning on arm32
tracing: Record trace_clock and recover when reboot
tracing/sched: Use __string() instead of fixed lengths for task->comm
tracepoint: Have tracepoints created with DECLARE_TRACE() have _tp suffix
tracing: Cleanup upper_empty() in pid_list
tracing: Allow the top level trace_marker to write into another instances
tracing: Add a helper function to handle the dereference arg in verifier
tracing: Remove unnecessary "goto out" that simply returns ret is trigger code
tracing: Fix error handling in event_trigger_parse()
tracing: Rename event_trigger_alloc() to trigger_data_alloc()
tracing: Replace deprecated strncpy() with strscpy() for stack_trace_filter_buf
tracing: Remove unused buffer_page field from trace_array_cpu structure
tracing: Use atomic_inc_return() for updating "disabled" counter in irqsoff tracer
tracing: Convert the per CPU "disabled" counter to local from atomic
tracing: branch: Use trace_tracing_is_on_cpu() instead of "disabled" field
ring-buffer: Add ring_buffer_record_is_on_cpu()
tracing: Do not use per CPU array_buffer.data->disabled for cpumask
ftrace: Do not disabled function graph based on "disabled" field
tracing: kdb: Use tracer_tracing_on/off() instead of setting per CPU disabled
tracing: Use tracer_tracing_disable() instead of "disabled" field for ftrace_dump_one()
...
The function rb_allocate_pages() allocates cpu_buffer and on error needs
to free it. It has a single return. Use __free(kfree) and return directly
on errors and have the return use return_ptr(cpu_buffer).
The function alloc_buffer() allocates buffer and on error needs to free
it. It has a single return. Use __free(kfree) and return directly on
errors and have the return use return_ptr(buffer).
The function __rb_map_vma() allocates a temporary array "pages". Have it
use __free() and not worry about freeing it when returning.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250527143144.6edc4625@gandalf.local.home
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Convert the taking of the buffer->mutex and the cpu_buffer->mapping_lock
over to guard(mutex) and simplify the ring_buffer_map() and
ring_buffer_unmap() functions.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250527122009.267efb72@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function ring_buffer_read_page() had two gotos. One was simply
returning "ret" and the other was unlocking the reader_lock.
There's no reason to use goto to simply return the "ret" variable. Instead
just return the value.
The jump to the unlocking of the reader_lock can be replaced by
guard(raw_spinlock_irqsave)(&cpu_buffer->reader_lock).
With these two changes the "ret" variable is no longer used and can be
removed. The return value on non-error is what was read and is stored in
the "read" variable.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250527145216.0187cf36@gandalf.local.home
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Use guard(raw_spinlock_irqsave)() in reset_disabled_cpu_buffer() to
simplify the locking.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250527144623.77a9cc47@gandalf.local.home
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function ring_buffer_swap_cpu() has a bunch of jumps to the label out
that simply returns "ret". There's no reason to jump to a label that
simply returns a value. Just return directly from there.
This goes back to almost the beginning when commit 8aabee573d
("ring-buffer: remove unneeded get_online_cpus") was introduced. That
commit removed a put_online_cpus() from that label, but never updated all
the jumps to it that now no longer needed to do anything but return a
value.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250527145753.6b45d840@gandalf.local.home
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In the function ring_buffer_discard_commit() there's an if statement that
jumps to the next line:
if (rb_try_to_discard(cpu_buffer, event))
goto out;
out:
This was caused by the change that modified the way timestamps were taken
in interrupt context, and removed the code between the if statement and
the goto, but failed to update the conditional logic.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250527155116.227f35be@gandalf.local.home
Fixes: a389d86f7f ("ring-buffer: Have nested events still record running time stamp")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reset the last-boot ring buffers when read() reads out all cpu
buffers through trace_pipe/trace_pipe_raw. This prevents ftrace to
unwind ring buffer read pointer next boot.
Note that this resets only when all per-cpu buffers are empty, and
read via read(2) syscall. For example, if you read only one of the
per-cpu trace_pipe, it does not reset it. Also, reading buffer by
splice(2) syscall does not reset because some data in the reader
(the last) page.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/174792929202.496143.8184644221859580999.stgit@mhiramat.tok.corp.google.com
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the persistent ring buffer is created from the memory returned by
reserve_mem there is nothing prohibiting it to be memory mapped to user
space. The memory is the same as the pages allocated by alloc_page().
The way the memory is managed by the ring buffer code is slightly
different though and needs to be addressed.
The persistent memory uses the page->id for its own purpose where as the
user mmap buffer currently uses that for the subbuf array mapped to user
space. If the buffer is a persistent buffer, use the page index into that
buffer as the identifier instead of the page->id.
That is, the page->id for a persistent buffer, represents the order of the
buffer is in the link list. ->id == 0 means it is the reader page.
When a reader page is swapped, the new reader page's ->id gets zero, and
the old reader page gets the ->id of the page that it swapped with.
The user space mapping has the ->id is the index of where it was mapped in
user space and does not change while it is mapped.
Since the persistent buffer is fixed in its location, the index of where
a page is in the memory range can be used as the "id" to put in the meta
page array, and it can be mapped in the same order to user space as it is
in the persistent memory.
A new rb_page_id() helper function is used to get and set the id depending
on if the page is a normal memory allocated buffer or a physical memory
mapped buffer.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/20250401203332.246646011@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When reading a memory mapped buffer the reader page is just swapped out
with the last page written in the write buffer. If the reader page is the
same as the commit buffer (the buffer that is currently being written to)
it was assumed that it should never have missed events. If it does, it
triggers a WARN_ON_ONCE().
But there just happens to be one scenario where this can legitimately
happen. That is on a commit_overrun. A commit overrun is when an interrupt
preempts an event being written to the buffer and then the interrupt adds
so many new events that it fills and wraps the buffer back to the commit.
Any new events would then be dropped and be reported as "missed_events".
In this case, the next page to read is the commit buffer and after the
swap of the reader page, the reader page will be the commit buffer, but
this time there will be missed events and this triggers the following
warning:
------------[ cut here ]------------
WARNING: CPU: 2 PID: 1127 at kernel/trace/ring_buffer.c:7357 ring_buffer_map_get_reader+0x49a/0x780
Modules linked in: kvm_intel kvm irqbypass
CPU: 2 UID: 0 PID: 1127 Comm: trace-cmd Not tainted 6.15.0-rc7-test-00004-g478bc2824b45-dirty #564 PREEMPT
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:ring_buffer_map_get_reader+0x49a/0x780
Code: 00 00 00 48 89 fe 48 c1 ee 03 80 3c 2e 00 0f 85 ec 01 00 00 4d 3b a6 a8 00 00 00 0f 85 8a fd ff ff 48 85 c0 0f 84 55 fe ff ff <0f> 0b e9 4e fe ff ff be 08 00 00 00 4c 89 54 24 58 48 89 54 24 50
RSP: 0018:ffff888121787dc0 EFLAGS: 00010002
RAX: 00000000000006a2 RBX: ffff888100062800 RCX: ffffffff8190cb49
RDX: ffff888126934c00 RSI: 1ffff11020200a15 RDI: ffff8881010050a8
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffed1024d26982
R10: ffff888126934c17 R11: ffff8881010050a8 R12: ffff888126934c00
R13: ffff8881010050b8 R14: ffff888101005000 R15: ffff888126930008
FS: 00007f95c8cd7540(0000) GS:ffff8882b576e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f95c8de4dc0 CR3: 0000000128452002 CR4: 0000000000172ef0
Call Trace:
<TASK>
? __pfx_ring_buffer_map_get_reader+0x10/0x10
tracing_buffers_ioctl+0x283/0x370
__x64_sys_ioctl+0x134/0x190
do_syscall_64+0x79/0x1c0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f95c8de48db
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007ffe037ba110 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffe037bb2b0 RCX: 00007f95c8de48db
RDX: 0000000000000000 RSI: 0000000000005220 RDI: 0000000000000006
RBP: 00007ffe037ba180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe037bb6f8 R14: 00007f95c9065000 R15: 00005575c7492c90
</TASK>
irq event stamp: 5080
hardirqs last enabled at (5079): [<ffffffff83e0adb0>] _raw_spin_unlock_irqrestore+0x50/0x70
hardirqs last disabled at (5080): [<ffffffff83e0aa83>] _raw_spin_lock_irqsave+0x63/0x70
softirqs last enabled at (4182): [<ffffffff81516122>] handle_softirqs+0x552/0x710
softirqs last disabled at (4159): [<ffffffff815163f7>] __irq_exit_rcu+0x107/0x210
---[ end trace 0000000000000000 ]---
The above was triggered by running on a kernel with both lockdep and KASAN
as well as kmemleak enabled and executing the following command:
# perf record -o perf-test.dat -a -- trace-cmd record --nosplice -e all -p function hackbench 50
With perf interjecting a lot of interrupts and trace-cmd enabling all
events as well as function tracing, with lockdep, KASAN and kmemleak
enabled, it could cause an interrupt preempting an event being written to
add enough events to wrap the buffer. trace-cmd was modified to have
--nosplice use mmap instead of reading the buffer.
The way to differentiate this case from the normal case of there only
being one page written to where the swap of the reader page received that
one page (which is the commit page), check if the tail page is on the
reader page. The difference between the commit page and the tail page is
that the tail page is where new writes go to, and the commit page holds
the first write that hasn't been committed yet. In the case of an
interrupt preempting the write of an event and filling the buffer, it
would move the tail page but not the commit page.
Have the warning only trigger if the tail page is also on the reader page,
and also print out the number of events dropped by a commit overrun as
that can not yet be safely added to the page so that the reader can see
there were events dropped.
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250528121555.2066527e@gandalf.local.home
Fixes: fe832be05a ("ring-buffer: Have mmapped ring buffer keep track of missed events")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
-----BEGIN PGP SIGNATURE-----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=j3t8
-----END PGP SIGNATURE-----
Merge tag 'bpf-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Fix and improve BTF deduplication of identical BTF types (Alan
Maguire and Andrii Nakryiko)
- Support up to 12 arguments in BPF trampoline on arm64 (Xu Kuohai and
Alexis Lothoré)
- Support load-acquire and store-release instructions in BPF JIT on
riscv64 (Andrea Parri)
- Fix uninitialized values in BPF_{CORE,PROBE}_READ macros (Anton
Protopopov)
- Streamline allowed helpers across program types (Feng Yang)
- Support atomic update for hashtab of BPF maps (Hou Tao)
- Implement json output for BPF helpers (Ihor Solodrai)
- Several s390 JIT fixes (Ilya Leoshkevich)
- Various sockmap fixes (Jiayuan Chen)
- Support mmap of vmlinux BTF data (Lorenz Bauer)
- Support BPF rbtree traversal and list peeking (Martin KaFai Lau)
- Tests for sockmap/sockhash redirection (Michal Luczaj)
- Introduce kfuncs for memory reads into dynptrs (Mykyta Yatsenko)
- Add support for dma-buf iterators in BPF (T.J. Mercier)
- The verifier support for __bpf_trap() (Yonghong Song)
* tag 'bpf-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (135 commits)
bpf, arm64: Remove unused-but-set function and variable.
selftests/bpf: Add tests with stack ptr register in conditional jmp
bpf: Do not include stack ptr register in precision backtracking bookkeeping
selftests/bpf: enable many-args tests for arm64
bpf, arm64: Support up to 12 function arguments
bpf: Check rcu_read_lock_trace_held() in bpf_map_lookup_percpu_elem()
bpf: Avoid __bpf_prog_ret0_warn when jit fails
bpftool: Add support for custom BTF path in prog load/loadall
selftests/bpf: Add unit tests with __bpf_trap() kfunc
bpf: Warn with __bpf_trap() kfunc maybe due to uninitialized variable
bpf: Remove special_kfunc_set from verifier
selftests/bpf: Add test for open coded dmabuf_iter
selftests/bpf: Add test for dmabuf_iter
bpf: Add open coded dmabuf iterator
bpf: Add dmabuf iterator
dma-buf: Rename debugfs symbols
bpf: Fix error return value in bpf_copy_from_user_dynptr
libbpf: Use mmap to parse vmlinux BTF from sysfs
selftests: bpf: Add a test for mmapable vmlinux BTF
btf: Allow mmap of vmlinux btf
...
On arm32, size_t is defined to be unsigned int, while PAGE_SIZE is
unsigned long. This hence triggers a compilation warning as min()
asserts the type of two operands to be equal. Casting PAGE_SIZE to size_t
solves this issue and works on other target architectures as well.
Compilation warning details:
kernel/trace/trace.c: In function 'tracing_splice_read_pipe':
./include/linux/minmax.h:20:28: warning: comparison of distinct pointer types lacks a cast
(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
^
./include/linux/minmax.h:26:4: note: in expansion of macro '__typecheck'
(__typecheck(x, y) && __no_side_effects(x, y))
^~~~~~~~~~~
...
kernel/trace/trace.c:6771:8: note: in expansion of macro 'min'
min((size_t)trace_seq_used(&iter->seq),
^~~
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20250526013731.1198030-1-pantaixi@huaweicloud.com
Fixes: f5178c41bb ("tracing: Fix oob write in trace_seq_to_buffer()")
Reviewed-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Pan Taixi <pantaixi@huaweicloud.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
* Move kern_table members out of kernel/sysctl.c
Moved a subset (tracing, panic, signal, stack_tracer and sparc) out of the
kern_table array. The goal is for kern_table to only have sysctl elements. All
this increases modularity by placing the ctl_tables closer to where they are
used while reducing the chances of merge conflicts in kernel/sysctl.c.
* Fixed sysctl unit test panic by relocating it to selftests
* Testing
These have been in linux-next from rc2, so they have had more than a month
worth of testing.
-----BEGIN PGP SIGNATURE-----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=45X2
-----END PGP SIGNATURE-----
Merge tag 'sysctl-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl
Pull sysctl updates from Joel Granados:
- Move kern_table members out of kernel/sysctl.c
Moved a subset (tracing, panic, signal, stack_tracer and sparc) out
of the kern_table array. The goal is for kern_table to only have
sysctl elements. All this increases modularity by placing the
ctl_tables closer to where they are used while reducing the chances
of merge conflicts in kernel/sysctl.c.
- Fixed sysctl unit test panic by relocating it to selftests
* tag 'sysctl-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl:
sysctl: Close test ctl_headers with a for loop
sysctl: call sysctl tests with a for loop
sysctl: Add 0012 to test the u8 range check
sysctl: move u8 register test to lib/test_sysctl.c
sparc: mv sparc sysctls into their own file under arch/sparc/kernel
stack_tracer: move sysctl registration to kernel/trace/trace_stack.c
tracing: Move trace sysctls into trace.c
signal: Move signal ctl tables into signal.c
panic: Move panic ctl tables into panic.c
-----BEGIN PGP SIGNATURE-----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=1PNK
-----END PGP SIGNATURE-----
Merge tag 'for-6.16/block-20250523' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:
- ublk updates:
- Add support for updating the size of a ublk instance
- Zero-copy improvements
- Auto-registering of buffers for zero-copy
- Series simplifying and improving GET_DATA and request lookup
- Series adding quiesce support
- Lots of selftests additions
- Various cleanups
- NVMe updates via Christoph:
- add per-node DMA pools and use them for PRP/SGL allocations
(Caleb Sander Mateos, Keith Busch)
- nvme-fcloop refcounting fixes (Daniel Wagner)
- support delayed removal of the multipath node and optionally
support the multipath node for private namespaces (Nilay Shroff)
- support shared CQs in the PCI endpoint target code (Wilfred
Mallawa)
- support admin-queue only authentication (Hannes Reinecke)
- use the crc32c library instead of the crypto API (Eric Biggers)
- misc cleanups (Christoph Hellwig, Marcelo Moreira, Hannes
Reinecke, Leon Romanovsky, Gustavo A. R. Silva)
- MD updates via Yu:
- Fix that normal IO can be starved by sync IO, found by mkfs on
newly created large raid5, with some clean up patches for bdev
inflight counters
- Clean up brd, getting rid of atomic kmaps and bvec poking
- Add loop driver specifically for zoned IO testing
- Eliminate blk-rq-qos calls with a static key, if not enabled
- Improve hctx locking for when a plug has IO for multiple queues
pending
- Remove block layer bouncing support, which in turn means we can
remove the per-node bounce stat as well
- Improve blk-throttle support
- Improve delay support for blk-throttle
- Improve brd discard support
- Unify IO scheduler switching. This should also fix a bunch of lockdep
warnings we've been seeing, after enabling lockdep support for queue
freezing/unfreezeing
- Add support for block write streams via FDP (flexible data placement)
on NVMe
- Add a bunch of block helpers, facilitating the removal of a bunch of
duplicated boilerplate code
- Remove obsolete BLK_MQ pci and virtio Kconfig options
- Add atomic/untorn write support to blktrace
- Various little cleanups and fixes
* tag 'for-6.16/block-20250523' of git://git.kernel.dk/linux: (186 commits)
selftests: ublk: add test for UBLK_F_QUIESCE
ublk: add feature UBLK_F_QUIESCE
selftests: ublk: add test case for UBLK_U_CMD_UPDATE_SIZE
traceevent/block: Add REQ_ATOMIC flag to block trace events
ublk: run auto buf unregisgering in same io_ring_ctx with registering
io_uring: add helper io_uring_cmd_ctx_handle()
ublk: remove io argument from ublk_auto_buf_reg_fallback()
ublk: handle ublk_set_auto_buf_reg() failure correctly in ublk_fetch()
selftests: ublk: add test for covering UBLK_AUTO_BUF_REG_FALLBACK
selftests: ublk: support UBLK_F_AUTO_BUF_REG
ublk: support UBLK_AUTO_BUF_REG_FALLBACK
ublk: register buffer to local io_uring with provided buf index via UBLK_F_AUTO_BUF_REG
ublk: prepare for supporting to register request buffer automatically
ublk: convert to refcount_t
selftests: ublk: make IO & device removal test more stressful
nvme: rename nvme_mpath_shutdown_disk to nvme_mpath_remove_disk
nvme: introduce multipath_always_on module param
nvme-multipath: introduce delayed removal of the multipath head node
nvme-pci: derive and better document max segments limits
nvme-pci: use struct_size for allocation struct nvme_dev
...
On error, copy_from_user returns number of bytes not copied to
destination, but current implementation of copy_user_data_sleepable does
not handle that correctly and returns it as error value, which may
confuse user, expecting meaningful negative error value.
Fixes: a498ee7576 ("bpf: Implement dynptr copy kfuncs")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250523181705.261585-1-mykyta.yatsenko5@gmail.com
Filesystems like XFS can implement atomic write I/O using either
REQ_ATOMIC flag set in the bio or via CoW operation. It will be useful
if we have a flag in trace events to distinguish between the two. This
patch adds char 'U' (Untorn writes) to rwbs field of the trace events
if REQ_ATOMIC flag is set in the bio.
<W/ REQ_ATOMIC>
=================
xfs_io-4238 [009] ..... 4148.126843: block_rq_issue: 259,0 WFSU 16384 () 768 + 32 none,0,0 [xfs_io]
<idle>-0 [009] d.h1. 4148.129864: block_rq_complete: 259,0 WFSU () 768 + 32 none,0,0 [0]
<W/O REQ_ATOMIC>
===============
xfs_io-4237 [010] ..... 4143.325616: block_rq_issue: 259,0 WS 16384 () 768 + 32 none,0,0 [xfs_io]
<idle>-0 [010] d.H1. 4143.329138: block_rq_complete: 259,0 WS () 768 + 32 none,0,0 [0]
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://lore.kernel.org/r/44317cb2ec4588f6a2c1501a96684e6a1196e8ba.1747921498.git.ritesh.list@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This reverts commit 4a8f635a60.
Althought get_pid_task() internally already calls rcu_read_lock() and
rcu_read_unlock(), the find_vpid() was not.
The documentation for find_vpid() clearly states:
"Must be called with the tasklist_lock or rcu_read_lock() held."
Add proper rcu_read_lock/unlock() to protect the find_vpid().
Fixes: 4a8f635a60 ("bpf: remove unnecessary rcu_read_{lock,unlock}() in multi-uprobe attach logic")
Reported-by: Xuewen Yan <xuewen.yan@unisoc.com>
Signed-off-by: Di Shen <di.shen@unisoc.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20250520054943.5002-1-xuewen.yan@unisoc.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
- Fix sample code that uses trace_array_printk()
The sample code for in kernel use of trace_array (that creates an instance
for use within the kernel) and shows how to use trace_array_printk() that
writes into the created instance, used trace_printk_init_buffers(). But
that function is used to initialize normal trace_printk() and produces the
NOTICE banner which is not needed for use of trace_array_printk(). The
function to initialize that is trace_array_init_printk() that takes the
created trace array instance as a parameter.
Update the sample code to reflect the proper usage.
- Fix preemption count output for stacktrace event
The tracing buffer shows the preempt count level when an event executes.
Because writing the event itself disables preemption, this needs to be
accounted for when recording. The stacktrace event did not account for
this so the output of the stacktrace event showed preemption was disabled
while the event that triggered the stacktrace shows preemption is enabled
and this leads to confusion. Account for preemption being disabled for the
stacktrace event.
The same happened for stack traces triggered by function tracer.
- Fix persistent ring buffer when trace_pipe is used
The ring buffer swaps the reader page with the next page to read from the
write buffer when trace_pipe is used. If there's only a page of data in
the ring buffer, this swap will cause the "commit" pointer (last data
written) to be on the reader page. If more data is written to the buffer,
it is added to the reader page until it falls off back into the write
buffer.
If the system reboots and the commit pointer is still on the reader page,
even if new data was written, the persistent buffer validator will miss
finding the commit pointer because it only checks the write buffer and
does not check the reader page. This causes the validator to fail the
validation and clear the buffer, where the new data is lost.
There was a check for this, but it checked the "head pointer", which was
incorrect, because the "head pointer" always stays on the write buffer and
is the next page to swap out for the reader page. Fix the logic to catch
this case and allow the user to still read the data after reboot.
-----BEGIN PGP SIGNATURE-----
iIoEABYKADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCaCTZHBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qu04AQDjOS46Y8d58MuwjLrQAotOUnANZADz
7d+5snlcMjhqkAEAo+zc2z9LgqBAnv1VG3GEPgac0JmyPeOnqSJRWRpRXAM=
=UveQ
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix sample code that uses trace_array_printk()
The sample code for in kernel use of trace_array (that creates an
instance for use within the kernel) and shows how to use
trace_array_printk() that writes into the created instance, used
trace_printk_init_buffers(). But that function is used to initialize
normal trace_printk() and produces the NOTICE banner which is not
needed for use of trace_array_printk(). The function to initialize
that is trace_array_init_printk() that takes the created trace array
instance as a parameter.
Update the sample code to reflect the proper usage.
- Fix preemption count output for stacktrace event
The tracing buffer shows the preempt count level when an event
executes. Because writing the event itself disables preemption, this
needs to be accounted for when recording. The stacktrace event did
not account for this so the output of the stacktrace event showed
preemption was disabled while the event that triggered the stacktrace
shows preemption is enabled and this leads to confusion. Account for
preemption being disabled for the stacktrace event.
The same happened for stack traces triggered by function tracer.
- Fix persistent ring buffer when trace_pipe is used
The ring buffer swaps the reader page with the next page to read from
the write buffer when trace_pipe is used. If there's only a page of
data in the ring buffer, this swap will cause the "commit" pointer
(last data written) to be on the reader page. If more data is written
to the buffer, it is added to the reader page until it falls off back
into the write buffer.
If the system reboots and the commit pointer is still on the reader
page, even if new data was written, the persistent buffer validator
will miss finding the commit pointer because it only checks the write
buffer and does not check the reader page. This causes the validator
to fail the validation and clear the buffer, where the new data is
lost.
There was a check for this, but it checked the "head pointer", which
was incorrect, because the "head pointer" always stays on the write
buffer and is the next page to swap out for the reader page. Fix the
logic to catch this case and allow the user to still read the data
after reboot.
* tag 'trace-v6.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Fix persistent buffer when commit page is the reader page
ftrace: Fix preemption accounting for stacktrace filter command
ftrace: Fix preemption accounting for stacktrace trigger command
tracing: samples: Initialize trace_array_printk() with the correct function
The ring buffer is made up of sub buffers (sometimes called pages as they
are by default PAGE_SIZE). It has the following "pages":
"tail page" - this is the page that the next write will write to
"head page" - this is the page that the reader will swap the reader page with.
"reader page" - This belongs to the reader, where it will swap the head
page from the ring buffer so that the reader does not
race with the writer.
The writer may end up on the "reader page" if the ring buffer hasn't
written more than one page, where the "tail page" and the "head page" are
the same.
The persistent ring buffer has meta data that points to where these pages
exist so on reboot it can re-create the pointers to the cpu_buffer
descriptor. But when the commit page is on the reader page, the logic is
incorrect.
The check to see if the commit page is on the reader page checked if the
head page was the reader page, which would never happen, as the head page
is always in the ring buffer. The correct check would be to test if the
commit page is on the reader page. If that's the case, then it can exit
out early as the commit page is only on the reader page when there's only
one page of data in the buffer. There's no reason to iterate the ring
buffer pages to find the "commit page" as it is already found.
To trigger this bug:
# echo 1 > /sys/kernel/tracing/instances/boot_mapped/events/syscalls/sys_enter_fchownat/enable
# touch /tmp/x
# chown sshd /tmp/x
# reboot
On boot up, the dmesg will have:
Ring buffer meta [0] is from previous boot!
Ring buffer meta [1] is from previous boot!
Ring buffer meta [2] is from previous boot!
Ring buffer meta [3] is from previous boot!
Ring buffer meta [4] commit page not found
Ring buffer meta [5] is from previous boot!
Ring buffer meta [6] is from previous boot!
Ring buffer meta [7] is from previous boot!
Where the buffer on CPU 4 had a "commit page not found" error and that
buffer is cleared and reset causing the output to be empty and the data lost.
When it works correctly, it has:
# cat /sys/kernel/tracing/instances/boot_mapped/trace_pipe
<...>-1137 [004] ..... 998.205323: sys_enter_fchownat: __syscall_nr=0x104 (260) dfd=0xffffff9c (4294967196) filename=(0xffffc90000a0002c) user=0x3e8 (1000) group=0xffffffff (4294967295) flag=0x0 (0
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250513115032.3e0b97f7@gandalf.local.home
Fixes: 5f3b6e839f ("ring-buffer: Validate boot range memory events")
Reported-by: Tasos Sahanidis <tasos@tasossah.com>
Tested-by: Tasos Sahanidis <tasos@tasossah.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When using the stacktrace trigger command to trace syscalls, the
preemption count was consistently reported as 1 when the system call
event itself had 0 (".").
For example:
root@ubuntu22-vm:/sys/kernel/tracing/events/syscalls/sys_enter_read
$ echo stacktrace > trigger
$ echo 1 > enable
sshd-416 [002] ..... 232.864910: sys_read(fd: a, buf: 556b1f3221d0, count: 8000)
sshd-416 [002] ...1. 232.864913: <stack trace>
=> ftrace_syscall_enter
=> syscall_trace_enter
=> do_syscall_64
=> entry_SYSCALL_64_after_hwframe
The root cause is that the trace framework disables preemption in __DO_TRACE before
invoking the trigger callback.
Use the tracing_gen_ctx_dec() that will accommodate for the increase of
the preemption count in __DO_TRACE when calling the callback. The result
is the accurate reporting of:
sshd-410 [004] ..... 210.117660: sys_read(fd: 4, buf: 559b725ba130, count: 40000)
sshd-410 [004] ..... 210.117662: <stack trace>
=> ftrace_syscall_enter
=> syscall_trace_enter
=> do_syscall_64
=> entry_SYSCALL_64_after_hwframe
Cc: stable@vger.kernel.org
Fixes: ce33c845b0 ("tracing: Dump stacktrace trigger to the corresponding instance")
Link: https://lore.kernel.org/20250512094246.1167956-1-dolinux.peng@gmail.com
Signed-off-by: pengdonglin <dolinux.peng@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Record trace_clock information in the trace_scratch area and recover
the trace_clock when boot, so that reader can docode the timestamp
correctly.
Note that since most trace_clocks records the timestamp in nano-
seconds, this is not a bug. But some trace_clock, like counter and
tsc will record the counter value. Only for those trace_clock user
needs this information.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/174720625803.1925039.1815089037443798944.stgit@mhiramat.tok.corp.google.com
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Instead of find_first_bit() use the dedicated bitmap_empty(),
and make upper_empty() a nice one-liner.
While there, fix opencoded BITS_PER_TYPE().
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250429195119.620204-1-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Since the shared trace_probe_log variable can be accessed and
modified via probe event create operation of kprobe_events,
uprobe_events, and dynamic_events, it should be protected.
In the dynamic_events, all operations are serialized by
`dyn_event_ops_mutex`. But kprobe_events and uprobe_events
interfaces are not serialized.
To solve this issue, introduces dyn_event_create(), which runs
create() operation under the mutex, for kprobe_events and
uprobe_events. This also uses lockdep to check the mutex is
held when using trace_probe_log* APIs.
Link: https://lore.kernel.org/all/174684868120.551552.3068655787654268804.stgit@devnote2/
Reported-by: Paul Cacheux <paulcacheux@gmail.com>
Closes: https://lore.kernel.org/all/20250510074456.805a16872b591e2971a4d221@kernel.org/
Fixes: ab105a4fb8 ("tracing: Use tracing error_log with probe events")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
This patch introduces a new set of kfuncs for working with dynptrs in
BPF programs, enabling reading variable-length user or kernel data
into dynptr directly. To enable memory-safety, verifier allows only
constant-sized reads via existing bpf_probe_read_{user|kernel} etc.
kfuncs, dynptr-based kfuncs allow dynamically-sized reads without memory
safety shortcomings.
The following kfuncs are introduced:
* `bpf_probe_read_kernel_dynptr()`: probes kernel-space data into a dynptr
* `bpf_probe_read_user_dynptr()`: probes user-space data into a dynptr
* `bpf_probe_read_kernel_str_dynptr()`: probes kernel-space string into
a dynptr
* `bpf_probe_read_user_str_dynptr()`: probes user-space string into a
dynptr
* `bpf_copy_from_user_dynptr()`: sleepable, copies user-space data into
a dynptr for the current task
* `bpf_copy_from_user_str_dynptr()`: sleepable, copies user-space string
into a dynptr for the current task
* `bpf_copy_from_user_task_dynptr()`: sleepable, copies user-space data
of the task into a dynptr
* `bpf_copy_from_user_task_str_dynptr()`: sleepable, copies user-space
string of the task into a dynptr
The implementation is built on two generic functions:
* __bpf_dynptr_copy
* __bpf_dynptr_copy_str
These functions take function pointers as arguments, enabling the
copying of data from various sources, including both kernel and user
space.
Use __always_inline for generic functions and callbacks to make sure the
compiler doesn't generate indirect calls into callbacks, which is more
expensive, especially on some kernel configurations. Inlining allows
compiler to put direct calls into all the specific callback implementations
(copy_user_data_sleepable, copy_user_data_nofault, and so on).
Reviewed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Link: https://lore.kernel.org/r/20250512205348.191079-3-mykyta.yatsenko5@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make sure trace_probe_log_clear is called in the tracing
eprobe code path, matching the trace_probe_log_init call.
Link: https://lore.kernel.org/all/20250504-fix-trace-probe-log-race-v3-1-9e99fec7eddc@gmail.com/
Signed-off-by: Paul Cacheux <paulcacheux@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
When CONFIG_PROVE_RCU_LIST is enabled, fprobe triggers the following
warning:
WARNING: suspicious RCU usage
kernel/trace/fprobe.c:457 RCU-list traversed in non-reader section!!
other info that might help us debug this:
#1: ffffffff863c4e08 (fprobe_mutex){+.+.}-{4:4}, at: fprobe_module_callback+0x7b/0x8c0
Call Trace:
fprobe_module_callback
notifier_call_chain
blocking_notifier_call_chain
This warning occurs because fprobe_remove_node_in_module() traverses an
RCU list using RCU primitives without holding an RCU read lock. However,
the function is only called from fprobe_module_callback(), which holds
the fprobe_mutex lock that provides sufficient protection for safely
traversing the list.
Fix the warning by specifying the locking design to the
CONFIG_PROVE_RCU_LIST mechanism. Add the lockdep_is_held() argument to
hlist_for_each_entry_rcu() to inform the RCU checker that fprobe_mutex
provides the required protection.
Link: https://lore.kernel.org/all/20250410-fprobe-v1-1-068ef5f41436@debian.org/
Fixes: a3dc2983ca ("tracing: fprobe: Cleanup fprobe hash when module unloading")
Signed-off-by: Breno Leitao <leitao@debian.org>
Tested-by: Antonio Quartulli <antonio@mandelbit.com>
Tested-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Adding support to retrieve ref_ctr_offset for uprobe perf link,
which got somehow omitted from the initial uprobe link info changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/bpf/20250509153539.779599-2-jolsa@kernel.org
There are applications that have it hard coded to write into the top level
trace_marker instance (/sys/kernel/tracing/trace_marker). This can be
annoying if a profiler is using that instance for other work, or if it
needs all writes to go into a new instance.
A new option is created called "copy_trace_marker". By default, the top
level has this set, as that is the default buffer that writing into the
top level trace_marker file will go to. But now if an instance is created
and sets this option, all writes into the top level trace_marker will also
be written into that instance buffer just as if an application were to
write into the instance's trace_marker file.
If the top level instance disables this option, then writes to its own
trace_marker and trace_marker_raw files will not go into its buffer.
If no instance has this option set, then the write will return an error
and errno will contain ENODEV.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250508095639.39f84eda@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a helper function called handle_dereference_arg() to replace the logic
that is identical in two locations of test_event_printk().
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250507191703.5dd8a61d@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There's several functions that have "goto out;" where the label out is just:
out:
return ret;
Simplify the code by just doing the return in the location and removing
all the out labels and jumps.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Link: https://lore.kernel.org/20250507145456.121186494@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
According to trigger_data_alloc() doc, trigger_data_free() should be
used to free an event_trigger_data object. This fixes a mismatch introduced
when kzalloc was replaced with trigger_data_alloc without updating
the corresponding deallocation calls.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Link: https://lore.kernel.org/20250507145455.944453325@goodmis.org
Link: https://lore.kernel.org/20250318112737.4174-1-linmq006@gmail.com
Fixes: e1f187d09e ("tracing: Have existing event_command.parse() implementations use helpers")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
[ SDR: Changed event_trigger_alloc/free() to trigger_data_alloc/free() ]
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function event_trigger_alloc() creates an event_trigger_data
descriptor and states that it needs to be freed via event_trigger_free().
This is incorrect, it needs to be freed by trigger_data_free() as
event_trigger_free() adds ref counting.
Rename event_trigger_alloc() to trigger_data_alloc() and state that it
needs to be freed via trigger_data_free(). This naming convention
was introducing bugs.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Link: https://lore.kernel.org/20250507145455.776436410@goodmis.org
Fixes: 86599dbe2c ("tracing: Add helper functions to simplify event_command.parse() callback handling")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The trace_array_cpu had a "buffer_page" field that was originally going to
be used as a backup page for the ring buffer. But the ring buffer has its
own way of reusing pages and this field was never used.
Remove it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.738849456@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The irqsoff tracer uses the per CPU "disabled" field to prevent corruption
of the accounting when it starts to trace interrupts disabled, but there's
a slight race that could happen if for some reason it was called twice.
Use atomic_inc_return() instead.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.567884756@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The per CPU "disabled" counter is used for the latency tracers and stack
tracers to make sure that their accounting isn't messed up by an NMI or
interrupt coming in and affecting the same CPU data. But the counter is an
atomic_t type. As it only needs to synchronize against the current CPU,
switch it over to local_t type.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.394925376@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The branch tracer currently checks the per CPU "disabled" field to know if
tracing is enabled or not for the CPU. As the "disabled" value is not used
anymore to turn of tracing generically, use tracing_tracer_is_on_cpu()
instead.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.224658526@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add the function ring_buffer_record_is_on_cpu() that returns true if the
ring buffer for a give CPU is writable and false otherwise.
Also add tracer_tracing_is_on_cpu() to return if the ring buffer for a
given CPU is writeable for a given trace_array.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.059853898@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
Do not bother setting the per CPU disabled flag of the array_buffer data
to use to determine what CPUs can write to the buffer and only rely on the
ring buffer code itself to disabled it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212235.885452497@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
Do not bother disabling the function graph tracer if the per CPU disabled
field is set. Just record as normal. If tracing is disabled in the ring
buffer it will not be recorded.
Also, when tracing is enabled again, it will not drop the return call of
the function.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212235.715752008@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
The kdb_ftdump() function iterates over all the current tracing CPUs and
increments the "disabled" counter before doing the dump, and decrements it
afterward.
As the disabled flag can be ignored, doing this today is not reliable.
Instead, simply call tracer_tracing_off() and then tracer_tracing_on() to
disable and then enabled the entire ring buffer in one go!
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Daniel Thompson <danielt@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/20250505212235.549033722@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
The ftrace_dump_one() function iterates over all the current tracing CPUs and
increments the "disabled" counter before doing the dump, and decrements it
afterward.
As the disabled flag can be ignored, doing this today is not reliable.
Instead use the new tracer_tracing_disable() that calls into the ring
buffer code to do the disabling.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212235.381188238@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Allow a tracer to disable writing to its buffer for a temporary amount of
time and re-enable it.
The tracer_tracing_disable() will disable writing to the trace array
buffer, and requires a tracer_tracing_enable() to re-enable it.
The difference between tracer_tracing_disable() and tracer_tracing_off()
is that the disable version can nest, and requires as many enable() calls
as disable() calls to re-enable the buffer. Where as the off() function
can be called multiple times and only requires a singe tracer_tracing_on()
to re-enable the buffer.
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Daniel Thompson <danielt@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/20250505212235.210330010@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ignore_pid boolean on the per CPU data descriptor is updated at
sched_switch when a new task is scheduled in. If the new task is to be
ignored, it is set to true, otherwise it is set to false. The current task
should always have the correct value as it is updated when the task is
scheduled in.
Instead of breaking up the read of this value, which requires preemption
to be disabled, just use this_cpu_read() which gives a snapshot of the
value. Since the value will always be correct for a given task (because
it's updated at sched switch) it doesn't need preemption disabled.
This will also allow trace events to be called with preemption enabled.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212235.038958766@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
There's no reason for the function tracer to check it, if tracing is
disabled, the ring buffer will not record the event anyway.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212234.868972758@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The mmiotracer referenced the per CPU array_buffer->data descriptor but
never actually used it. Remove the references to it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212234.696945463@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Allocate kernel memory for processing CPU string
(/sys/kernel/tracing/osnoise/cpus) also in osnoise_cpus_write to allow
the writing of a CPU string of an arbitrary length.
This replaces the 256-byte buffer, which is insufficient with the rising
number of CPUs. For example, if I wanted to measure on every even CPU
on a system with 256 CPUs, the string would be 456 characters long.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250425091839.343289-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The structure ftrace_func_mapper only contains a single field and that is
a ftrace_hash. It is used to abstract it out from a normal hash to control
users of how it gets modified.
The freeing of a ftrace_func_mapper structure is:
free_ftrace_hash(&mapper->hash);
Without context, this looks like a bug. It should be commented that it is
not a bug and it is freed this way.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/20250416165420.5c717420@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Depth is stored as int because the code uses negative values to break
out of iterations. But what is recorded is always zero or positive. So
expose it as unsigned int instead of int.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250412221847.17310-3-iii@linux.ibm.com
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function graph infrastructure uses subops of the function tracer.
These are not shown in enabled_functions. Add a "subops:" section to the
enabled_functions line to show what functions are attached via subops. If
the subops is from the function_graph infrastructure, then show the entry
and return callbacks that are attached.
Here's an example of the output:
schedule_on_each_cpu (1) tramp: 0xffffffffc03ef000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 subops: {ent:trace_graph_entry+0x0/0x20 ret:trace_graph_return+0x0/0x150}
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250410153830.5d97f108@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The last remaining user of vfs_submount() (tracefs) is easy to convert
to fs_context_for_submount(); do that and bury that thing, along with
SB_SUBMOUNT
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Tested-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If one wants to trace the name of the task that wakes up a process and
pass that to the synthetic events, there's nothing currently that lets the
synthetic events do that. Add a "common_comm" to the histogram logic that
allows histograms save the current->comm as a variable that can be passed
through and added to a synthetic event:
# cd /sys/kernel/tracing
# echo 's:wake_lat char[] waker; char[] wakee; u64 delta;' >> dynamic_events
# echo 'hist:keys=pid:comm=common_comm:ts=common_timestamp.usecs if !(common_flags & 0x18)' > events/sched/sched_waking/trigger
# echo 'hist:keys=next_pid:wake_comm=$comm:delta=common_timestamp.usecs-$ts:onmatch(sched.sched_waking).trace(wake_lat,$wake_comm,next_comm,$delta)' > events/sched/sched_switch/trigger
The above will create a synthetic trace event that will save both the name
of the waker and the wakee but only if the wakeup did not happen in a hard
or soft interrupt context.
The "common_comm" is used to save the task->comm at the time of the
initial event and is passed via the "comm" variable to the second event,
and that is saved as the "waker" field in the "wake_lat" synthetic event.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250407154912.3c6c6246@gandalf.local.home
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The histogram trigger has three somewhat large arrays on the kernel stack:
unsigned long entries[HIST_STACKTRACE_DEPTH];
u64 var_ref_vals[TRACING_MAP_VARS_MAX];
char compound_key[HIST_KEY_SIZE_MAX];
Checking the function event_hist_trigger() stack frame size, it currently
uses 816 bytes for its stack frame due to these variables!
Instead, allocate a per CPU structure that holds these arrays for each
context level (normal, softirq, irq and NMI). That is, each CPU will have
4 of these structures. This will be allocated when the first histogram
trigger is enabled and freed when the last is disabled. When the
histogram callback triggers, it will request this structure. The request
will disable preemption, get the per CPU structure at the index of the
per CPU variable, and increment that variable.
The callback will use the arrays in this structure to perform its work and
then release the structure. That in turn will simply decrement the per CPU
index and enable preemption.
Moving the variables from the kernel stack to the per CPU structure brings
the stack frame of event_hist_trigger() down to just 112 bytes.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Link: https://lore.kernel.org/20250407123851.74ea8d58@gandalf.local.home
Fixes: 067fe038e7 ("tracing: Add variable reference handling to hist triggers")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The add_to_key() function tests if the key is a string or some data. If
it's a string it does some further calculations of the string size (still
truncating it to the max size it can be), and calls strncpy().
If the key isn't as string it calls memcpy(). The interesting point is
that both use the exact same parameters:
strncpy(compound_key + key_field->offset, (char *)key, size);
} else
memcpy(compound_key + key_field->offset, key, size);
As strncpy() is being used simply as a memcpy() for a string, and since
strncpy() is deprecated, just call memcpy() for both memory and string
keys.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/20250403210637.1c477d4a@gandalf.local.home
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the "fields" option is set in a trace instance, it ignores the "print fmt"
portion of the trace event and just prints the raw fields defined by the
TP_STRUCT__entry() of the TRACE_EVENT() macro.
The preempt_disable/enable and irq_disable/enable events record only the
caller offset from _stext to save space in the ring buffer. Even though
the "fields" option only prints the fields, it also tries to print what
they represent too, which includes function names.
Add a check in the output of the event field printing to see if the field
name is "caller_offs" or "parent_offs" and then print the function at the
offset from _stext of that field.
Instead of just showing:
irq_disable: caller_offs=0xba634d (12215117) parent_offs=0x39d10e2 (60625122)
Show:
irq_disable: caller_offs=trace_hardirqs_off.part.0+0xad/0x130 0xba634d (12215117) parent_offs=_raw_spin_lock_irqsave+0x62/0x70 0x39d10e2 (60625122)
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250506105131.4b6089a9@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add adjustments to the values of the "fields" output if the buffer is a
persistent ring buffer to adjust the addresses to both the kernel core and
kernel modules if they match a module in the persistent memory and that
module is also loaded.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250325185619.54b85587@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The trace_adjust_address() will take a given address and examine the
persistent ring buffer to see if the address matches a module that is
listed there. If it does not, it will just adjust the value to the core
kernel delta. But if the address was for something that was not part of
the core kernel text or data it should not be adjusted.
Check the result of the adjustment and only return the adjustment if it
lands in the current kernel text or data. If not, return the original
address.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250506102300.0ba2f9e0@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the "fields" option is enabled, the "print fmt" of the trace event is
ignored and only the fields are printed. But some fields contain function
pointers. Instead of just showing the hex value in this case, show the
function name when possible:
Instead of having:
# echo 1 > options/fields
# cat trace
[..]
kmem_cache_free: call_site=0xffffffffa9afcf31 (-1448095951) ptr=0xffff888124452910 (-131386736039664) name=kmemleak_object
Have it output:
kmem_cache_free: call_site=rcu_do_batch+0x3d1/0x14a0 (-1768960207) ptr=0xffff888132ea5ed0 (854220496) name=kmemleak_object
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250325213919.624181915@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Now that module addresses are saved in the persistent ring buffer, their
addresses can be used to adjust the address in the persistent ring buffer
to the address of the module that is currently loaded.
Instead of blindly using the text_delta that only works for core kernel
code, call the trace_adjust_address() that will see if the address matches
an address saved in the persistent ring buffer, and then uses that against
the matching module if it is loaded.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250506111648.5df7f3ec@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The block layer bounce buffering support is unused now, remove it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250505081138.3435992-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently the calling conventions for ->d_automount() instances have
an odd wart - returned new mount to be attached is expected to have
refcount 2.
That kludge is intended to make sure that mark_mounts_for_expiry() called
before we get around to attaching that new mount to the tree won't decide
to take it out. finish_automount() drops the extra reference after it's
done with attaching mount to the tree - or drops the reference twice in
case of error. ->d_automount() instances have rather counterintuitive
boilerplate in them.
There's a much simpler approach: have mark_mounts_for_expiry() skip the
mounts that are yet to be mounted. And to hell with grabbing/dropping
those extra references. Makes for simpler correctness analysis, at that...
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Acked-by: David Howells <dhowells@redhat.com>
Tested-by: David Howells <dhowells@redhat.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The function trace_adjust_address() is used to map addresses of modules
stored in the persistent memory and are also loaded in the current boot to
return the current address for the module.
If there's only one module entry, it will simply use that, otherwise it
performs a bsearch of the entry array to find the modules to offset with.
The issue is if there are no modules in the array. The code does not
account for that and ends up referencing the first element in the array
which does not exist and causes a crash.
If nr_entries is zero, exit out early as if this was a core kernel
address.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250501151909.65910359@gandalf.local.home
Fixes: 35a380ddbc ("tracing: Show last module text symbols in the stacktrace")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The check for a failed memory location is incorrectly checking
the wrong level of pointer indirection by checking !filter_hash
rather than !*filter_hash. Fix this.
Cc: asami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250422221335.89896-1-colin.i.king@gmail.com
Fixes: 0ae6b8ce20 ("ftrace: Fix accounting of subop hashes")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
syzbot reported this bug:
==================================================================
BUG: KASAN: slab-out-of-bounds in trace_seq_to_buffer kernel/trace/trace.c:1830 [inline]
BUG: KASAN: slab-out-of-bounds in tracing_splice_read_pipe+0x6be/0xdd0 kernel/trace/trace.c:6822
Write of size 4507 at addr ffff888032b6b000 by task syz.2.320/7260
CPU: 1 UID: 0 PID: 7260 Comm: syz.2.320 Not tainted 6.15.0-rc1-syzkaller-00301-g3bde70a2c827 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xc3/0x670 mm/kasan/report.c:521
kasan_report+0xe0/0x110 mm/kasan/report.c:634
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
__asan_memcpy+0x3c/0x60 mm/kasan/shadow.c:106
trace_seq_to_buffer kernel/trace/trace.c:1830 [inline]
tracing_splice_read_pipe+0x6be/0xdd0 kernel/trace/trace.c:6822
....
==================================================================
It has been reported that trace_seq_to_buffer() tries to copy more data
than PAGE_SIZE to buf. Therefore, to prevent this, we should use the
smaller of trace_seq_used(&iter->seq) and PAGE_SIZE as an argument.
Link: https://lore.kernel.org/20250422113026.13308-1-aha310510@gmail.com
Reported-by: syzbot+c8cd2d2c412b868263fb@syzkaller.appspotmail.com
Fixes: 3c56819b14 ("tracing: splice support for tracing_pipe")
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Many conditional checks in switch-case are redundant
with bpf_base_func_proto and should be removed.
Regarding the permission checks bpf_base_func_proto:
The permission checks in bpf_prog_load (as outlined below)
ensure that the trace has both CAP_BPF and CAP_PERFMON capabilities,
thus enabling the use of corresponding prototypes
in bpf_base_func_proto without adverse effects.
bpf_prog_load
......
bpf_cap = bpf_token_capable(token, CAP_BPF);
......
if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
type != BPF_PROG_TYPE_CGROUP_SKB &&
!bpf_cap)
goto put_token;
......
if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON))
goto put_token;
......
Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20250423073151.297103-1-yangfeng59949@163.com
The filter string testing uses strncpy_from_kernel/user_nofault() to
retrieve the string to test the filter against. The if() statement was
incorrect as it considered 0 as a fault, when it is only negative that it
faulted.
Running the following commands:
# cd /sys/kernel/tracing
# echo "filename.ustring ~ \"/proc*\"" > events/syscalls/sys_enter_openat/filter
# echo 1 > events/syscalls/sys_enter_openat/enable
# ls /proc/$$/maps
# cat trace
Would produce nothing, but with the fix it will produce something like:
ls-1192 [007] ..... 8169.828333: sys_openat(dfd: ffffffffffffff9c, filename: 7efc18359904, flags: 80000, mode: 0)
Link: https://lore.kernel.org/all/CAEf4BzbVPQ=BjWztmEwBPRKHUwNfKBkS3kce-Rzka6zvbQeVpg@mail.gmail.com/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250417183003.505835fb@gandalf.local.home
Fixes: 77360f9bbc ("tracing: Add test for user space strings when filtering on string pointers")
Reported-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Reported-by: Mykyta Yatsenko <mykyta.yatsenko5@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
ftrace_graph_ent.depth is int, but ftrace_graph_ent_entry.depth is
unsigned long. This confuses trace-cmd on 64-bit big-endian systems and
makes it print a huge amount of spaces. Fix this by using unsigned int,
which has a matching size, instead.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250412221847.17310-2-iii@linux.ibm.com
Fixes: ff5c9c576e ("ftrace: Add support for function argument to graph tracer")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The maximum of the ftrace hash bits is made fls(32) in
register_ftrace_direct(), which seems illogical. So, we fix it by making
the max hash bits FTRACE_HASH_MAX_BITS instead.
Link: https://lore.kernel.org/20250413014444.36724-1-dongml2@chinatelecom.cn
Fixes: d05cb47066 ("ftrace: Fix modification of direct_function hash while in use")
Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The subops processing creates new hashes when adding and removing subops.
There were some places that the old hashes that were replaced were not
freed and this caused some memory leaks.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250417135939.245b128d@gandalf.local.home
Fixes: 0ae6b8ce20 ("ftrace: Fix accounting of subop hashes")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There's several locations that free a ftrace hash pointer but may be
referenced again. Reset them to EMPTY_HASH so that a u-a-f bug doesn't
happen.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250417110933.20ab718b@gandalf.local.home
Fixes: 0ae6b8ce20 ("ftrace: Fix accounting of subop hashes")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The reworking to fix and simplify the ftrace_startup_subops() and the
ftrace_shutdown_subops() made it possible for the filter_hash and
notrace_hash variables to be used uninitialized in a way that the compiler
did not catch it.
Initialize both filter_hash and notrace_hash to the EMPTY_HASH as that is
what they should be if they never are used.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250417104017.3aea66c2@gandalf.local.home
Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Fixes: 0ae6b8ce20 ("ftrace: Fix accounting of subop hashes")
Closes: https://lore.kernel.org/all/1db64a42-626d-4b3a-be08-c65e47333ce2@linux.ibm.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Hide get_vm_area() from MMUless builds
The function get_vm_area() is not defined when CONFIG_MMU is not defined.
Hide that function within #ifdef CONFIG_MMU.
- Fix output of synthetic events when they have dynamic strings
The print fmt of the synthetic event's format file use to have "%.*s" for
dynamic size strings even though the user space exported arguments had
only __get_str() macro that provided just a nul terminated string. This
was fixed so that user space could parse this properly. But the reason
that it had "%.*s" was because internally it provided the maximum size of
the string as one of the arguments. The fix that replaced "%.*s" with "%s"
caused the trace output (when the kernel reads the event) to write
"(efault)" as it would now read the length of the string as "%s".
As the string provided is always nul terminated, there's no reason for the
internal code to use "%.*s" anyway. Just remove the length argument to
match the "%s" that is now in the format.
- Fix the ftrace subops hash logic of the manager ops hash
The function_graph uses the ftrace subops code. The subops code is a way
to have a single ftrace_ops registered with ftrace to determine what
functions will call the ftrace_ops callback. More than one user of
function graph can register a ftrace_ops with it. The function graph
infrastructure will then add this ftrace_ops as a subops with the main
ftrace_ops it registers with ftrace. This is because the functions will
always call the function graph callback which in turn calls the subops
ftrace_ops callbacks.
The main ftrace_ops must add a callback to all the functions that the
subops want a callback from. When a subops is registered, it will update
the main ftrace_ops hash to include the functions it wants. This is the
logic that was broken.
The ftrace_ops hash has a "filter_hash" and a "notrace_hash" were all the
functions in the filter_hash but not in the notrace_hash are attached by
ftrace. The original logic would have the main ftrace_ops filter_hash be a
union of all the subops filter_hashes and the main notrace_hash would be a
intersect of all the subops filter hashes. But this was incorrect because
the notrace hash depends on the filter_hash it is associated to and not
the union of all filter_hashes.
Instead, when a subops is added, just include all the functions of the
subops hash that are in its filter_hash but not in its notrace_hash. The
main subops hash should not use its notrace hash, unless all of its subops
hashes have an empty filter_hash (which means to attach to all functions),
and then, and only then, the main ftrace_ops notrace hash can be the
intersect of all the subops hashes.
This not only fixes the bug, but also simplifies the code.
- Add a selftest to better test the subops filtering
Add a selftest that would catch the bug fixed by the above change.
- Fix extra newline printed in function tracing with retval
The function parameter code changed the output logic slightly and called
print_graph_retval() and also printed a newline. The print_graph_retval()
also prints a newline which caused blank lines to be printed in the
function graph tracer when retval was added. This caused one of the
selftests to fail if retvals were enabled. Instead remove the new line
output from print_graph_retval() and have the callers always print the
new line so that it doesn't have to do special logic if it calls
print_graph_retval() or not.
- Fix out-of-bound memory access in the runtime verifier
When rv_is_container_monitor() is called on the last entry on the link
list it references the next entry, which is the list head and causes an
out-of-bound memory access.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ/rXQxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qoj7AQC0C2awpJSUIRj91qjPtMYuNUE3AVpB
EEZEkt19LfE//gEA1fOx3Cors/LrY9dthn/3LMKL23vo9c4i0ffhs2X+1gE=
=XJL5
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
- Hide get_vm_area() from MMUless builds
The function get_vm_area() is not defined when CONFIG_MMU is not
defined. Hide that function within #ifdef CONFIG_MMU.
- Fix output of synthetic events when they have dynamic strings
The print fmt of the synthetic event's format file use to have "%.*s"
for dynamic size strings even though the user space exported
arguments had only __get_str() macro that provided just a nul
terminated string. This was fixed so that user space could parse this
properly.
But the reason that it had "%.*s" was because internally it provided
the maximum size of the string as one of the arguments. The fix that
replaced "%.*s" with "%s" caused the trace output (when the kernel
reads the event) to write "(efault)" as it would now read the length
of the string as "%s".
As the string provided is always nul terminated, there's no reason
for the internal code to use "%.*s" anyway. Just remove the length
argument to match the "%s" that is now in the format.
- Fix the ftrace subops hash logic of the manager ops hash
The function_graph uses the ftrace subops code. The subops code is a
way to have a single ftrace_ops registered with ftrace to determine
what functions will call the ftrace_ops callback. More than one user
of function graph can register a ftrace_ops with it. The function
graph infrastructure will then add this ftrace_ops as a subops with
the main ftrace_ops it registers with ftrace. This is because the
functions will always call the function graph callback which in turn
calls the subops ftrace_ops callbacks.
The main ftrace_ops must add a callback to all the functions that the
subops want a callback from. When a subops is registered, it will
update the main ftrace_ops hash to include the functions it wants.
This is the logic that was broken.
The ftrace_ops hash has a "filter_hash" and a "notrace_hash" where
all the functions in the filter_hash but not in the notrace_hash are
attached by ftrace. The original logic would have the main ftrace_ops
filter_hash be a union of all the subops filter_hashes and the main
notrace_hash would be a intersect of all the subops filter hashes.
But this was incorrect because the notrace hash depends on the
filter_hash it is associated to and not the union of all
filter_hashes.
Instead, when a subops is added, just include all the functions of
the subops hash that are in its filter_hash but not in its
notrace_hash. The main subops hash should not use its notrace hash,
unless all of its subops hashes have an empty filter_hash (which
means to attach to all functions), and then, and only then, the main
ftrace_ops notrace hash can be the intersect of all the subops
hashes.
This not only fixes the bug, but also simplifies the code.
- Add a selftest to better test the subops filtering
Add a selftest that would catch the bug fixed by the above change.
- Fix extra newline printed in function tracing with retval
The function parameter code changed the output logic slightly and
called print_graph_retval() and also printed a newline. The
print_graph_retval() also prints a newline which caused blank lines
to be printed in the function graph tracer when retval was added.
This caused one of the selftests to fail if retvals were enabled.
Instead remove the new line output from print_graph_retval() and have
the callers always print the new line so that it doesn't have to do
special logic if it calls print_graph_retval() or not.
- Fix out-of-bound memory access in the runtime verifier
When rv_is_container_monitor() is called on the last entry on the
link list it references the next entry, which is the list head and
causes an out-of-bound memory access.
* tag 'trace-v6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
rv: Fix out-of-bound memory access in rv_is_container_monitor()
ftrace: Do not have print_graph_retval() add a newline
tracing/selftest: Add test to better test subops filtering of function graph
ftrace: Fix accounting of subop hashes
ftrace: Properly merge notrace hashes
tracing: Do not add length to print format in synthetic events
tracing: Hide get_vm_area() from MMUless builds
When rv_is_container_monitor() is called on the last monitor in
rv_monitors_list, KASAN yells:
BUG: KASAN: global-out-of-bounds in rv_is_container_monitor+0x101/0x110
Read of size 8 at addr ffffffff97c7c798 by task setup/221
The buggy address belongs to the variable:
rv_monitors_list+0x18/0x40
This is due to list_next_entry() is called on the last entry in the list.
It wraps around to the first list_head, and the first list_head is not
embedded in struct rv_monitor_def.
Fix it by checking if the monitor is last in the list.
Cc: stable@vger.kernel.org
Cc: Gabriele Monaco <gmonaco@redhat.com>
Fixes: cb85c660fc ("rv: Add option for nested monitors and include sched")
Link: https://lore.kernel.org/e85b5eeb7228bfc23b8d7d4ab5411472c54ae91b.1744355018.git.namcao@linutronix.de
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The retval and retaddr options for function_graph tracer will add a
comment at the end of a function for both leaf and non leaf functions that
looks like:
__wake_up_common(); /* ret=0x1 */
} /* pick_next_task_fair ret=0x0 */
The function print_graph_retval() adds a newline after the "*/". But if
that's not called, the caller function needs to make sure there's a
newline added.
This is confusing and when the function parameters code was added, it
added a newline even when calling print_graph_retval() as the fact that
the print_graph_retval() function prints a newline isn't obvious.
This caused an extra newline to be printed and that made it fail the
selftests when the retval option was set, as the selftests were not
expecting blank lines being injected into the trace.
Instead of having print_graph_retval() print a newline, just have the
caller always print the newline regardless if it calls print_graph_retval()
or not. This not only fixes this bug, but it also simplifies the code.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250411133015.015ca393@gandalf.local.home
Reported-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/all/ccc40f2b-4b9e-4abd-8daf-d22fce2a86f0@sirena.org.uk/
Fixes: ff5c9c576e ("ftrace: Add support for function argument to graph tracer")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function graph infrastructure uses ftrace to hook to functions. It has
a single ftrace_ops to manage all the users of function graph. Each
individual user (tracing, bpf, fprobes, etc) has its own ftrace_ops to
track the functions it will have its callback called from. These
ftrace_ops are "subops" to the main ftrace_ops of the function graph
infrastructure.
Each ftrace_ops has a filter_hash and a notrace_hash that is defined as:
Only trace functions that are in the filter_hash but not in the
notrace_hash.
If the filter_hash is empty, it means to trace all functions.
If the notrace_hash is empty, it means do not disable any function.
The function graph main ftrace_ops needs to be a superset containing all
the functions to be traced by all the subops it has. The algorithm to
perform this merge was incorrect.
When the first subops was added to the main ops, it simply made the main
ops a copy of the subops (same filter_hash and notrace_hash).
When a second ops was added, it joined the new subops filter_hash with the
main ops filter_hash as a union of the two sets. The intersect between the
new subops notrace_hash and the main ops notrace_hash was created as the
new notrace_hash of the main ops.
The issue here is that it would then start tracing functions than no
subops were tracing. For example if you had two subops that had:
subops 1:
filter_hash = '*sched*' # trace all functions with "sched" in it
notrace_hash = '*time*' # except do not trace functions with "time"
subops 2:
filter_hash = '*lock*' # trace all functions with "lock" in it
notrace_hash = '*clock*' # except do not trace functions with "clock"
The intersect of '*time*' functions with '*clock*' functions could be the
empty set. That means the main ops will be tracing all functions with
'*time*' and all "*clock*" in it!
Instead, modify the algorithm to be a bit simpler and correct.
First, when adding a new subops, even if it's the first one, do not add
the notrace_hash if the filter_hash is not empty. Instead, just add the
functions that are in the filter_hash of the subops but not in the
notrace_hash of the subops into the main ops filter_hash. There's no
reason to add anything to the main ops notrace_hash.
The notrace_hash of the main ops should only be non empty iff all subops
filter_hashes are empty (meaning to trace all functions) and all subops
notrace_hashes include the same functions.
That is, the main ops notrace_hash is empty if any subops filter_hash is
non empty.
The main ops notrace_hash only has content in it if all subops
filter_hashes are empty, and the content are only functions that intersect
all the subops notrace_hashes. If any subops notrace_hash is empty, then
so is the main ops notrace_hash.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Andy Chiu <andybnac@gmail.com>
Link: https://lore.kernel.org/20250409152720.216356767@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The global notrace hash should be jointly decided by the intersection of
each subops's notrace hash, but not the filter hash.
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20250408160258.48563-1-andybnac@gmail.com
Fixes: 5fccc7552c ("ftrace: Add subops logic to allow one ops to manage many")
Signed-off-by: Andy Chiu <andybnac@gmail.com>
[ fixed removing of freeing of filter_hash ]
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The link_create.flags are currently not used for multi-uprobes, so return
-EINVAL if it is set, same as for other attach APIs.
We allow target_fd to have an arbitrary value for multi-uprobe, though,
as there are existing users (libbpf) relying on this.
Fixes: 89ae89f53d ("bpf: Add multi uprobe link")
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250407035752.1108927-2-chen.dylane@linux.dev
The link_create.flags are currently not used for multi-kprobes, so return
-EINVAL if it is set, same as for other attach APIs.
We allow target_fd, on the other hand, to have an arbitrary value for
multi-kprobe, as there are existing users (libbpf) relying on this.
Fixes: 0dcac27254 ("bpf: Add multi kprobe link")
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250407035752.1108927-1-chen.dylane@linux.dev
The following causes a vsnprintf fault:
# echo 's:wake_lat char[] wakee; u64 delta;' >> /sys/kernel/tracing/dynamic_events
# echo 'hist:keys=pid:ts=common_timestamp.usecs if !(common_flags & 0x18)' > /sys/kernel/tracing/events/sched/sched_waking/trigger
# echo 'hist:keys=next_pid:delta=common_timestamp.usecs-$ts:onmatch(sched.sched_waking).trace(wake_lat,next_comm,$delta)' > /sys/kernel/tracing/events/sched/sched_switch/trigger
Because the synthetic event's "wakee" field is created as a dynamic string
(even though the string copied is not). The print format to print the
dynamic string changed from "%*s" to "%s" because another location
(__set_synth_event_print_fmt()) exported this to user space, and user
space did not need that. But it is still used in print_synth_event(), and
the output looks like:
<idle>-0 [001] d..5. 193.428167: wake_lat: wakee=(efault)sshd-sessiondelta=155
sshd-session-879 [001] d..5. 193.811080: wake_lat: wakee=(efault)kworker/u34:5delta=58
<idle>-0 [002] d..5. 193.811198: wake_lat: wakee=(efault)bashdelta=91
bash-880 [002] d..5. 193.811371: wake_lat: wakee=(efault)kworker/u35:2delta=21
<idle>-0 [001] d..5. 193.811516: wake_lat: wakee=(efault)sshd-sessiondelta=129
sshd-session-879 [001] d..5. 193.967576: wake_lat: wakee=(efault)kworker/u34:5delta=50
The length isn't needed as the string is always nul terminated. Just print
the string and not add the length (which was hard coded to the max string
length anyway).
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Douglas Raillard <douglas.raillard@arm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://lore.kernel.org/20250407154139.69955768@gandalf.local.home
Fixes: 4d38328eb4 ("tracing: Fix synth event printk format for str fields");
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Move stack_tracer_enabled into trace_stack_sysctl_table. This is part of
a greater effort to move ctl tables into their respective subsystems
which will reduce the merge conflicts in kernel/sysctl.c.
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Joel Granados <joel.granados@kernel.org>
Move trace ctl tables into their own const array in
kernel/trace/trace.c. The sysctl table register is called with
subsys_initcall placing if after its original place in proc_root_init.
This is part of a greater effort to move ctl tables into their
respective subsystems which will reduce the merge conflicts in
kernel/sysctl.c.
Signed-off-by: Joel Granados <joel.granados@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- fprobe: Fix to remove fprobe_hlist_node when module unloading
When a fprobe target module is removed, the fprobe_hlist_node
should be removed from the fprobe's hash table to prevent reusing
accidentally if another module is loaded at the same address.
- fprobe: Fix to lock module while registering fprobe
The module containing the function to be probeed is locked using a
reference counter until the fprobe registration is complete, which
prevents use after free.
- fprobe-events: Fix possible UAF on modules
Basically as same as above, but in the fprobe-events layer we also
need to get module reference counter when we find the tracepoint
in the module.
-----BEGIN PGP SIGNATURE-----
iQFPBAABCgA5FiEEh7BulGwFlgAOi5DV2/sHvwUrPxsFAmf0kJ8bHG1hc2FtaS5o
aXJhbWF0c3VAZ21haWwuY29tAAoJENv7B78FKz8b+bEIALiFuYBn2y26OJnfaRnW
rgSC2JupswEVg7HwsN5kA/x1ypXl9SPfJGjbiHLUTq9+4KGOBTmY+k5/OpVO+Qkh
3nYKOkZxKRTglA7hRSTH0rxDV1eobps4nv/xkPjprugcjCGU54+4yb9Hq7Kyflpa
o8p+VS/0VOJ9f3Iy9a9JRfu9qE7Qzz9USCj4N64WMgx/qczPe27twqFEaUpTf1VW
Sw9twtKnqGs9hNE2QmhlzUBuq6gOZMXkjH6t1U4pMWBGB51JqZ5ZBhC4kL/5XEIZ
bEau82El5qdieQC2B7c0RxldceKa4t4QUlJDalZGKpxvTXrCw9rFyv0dRe2cXnKm
Yo0=
=I+MO
-----END PGP SIGNATURE-----
Merge tag 'probes-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes fixes from Masami Hiramatsu:
- fprobe: remove fprobe_hlist_node when module unloading
When a fprobe target module is removed, the fprobe_hlist_node should
be removed from the fprobe's hash table to prevent reusing
accidentally if another module is loaded at the same address.
- fprobe: lock module while registering fprobe
The module containing the function to be probeed is locked using a
reference counter until the fprobe registration is complete, which
prevents use after free.
- fprobe-events: fix possible UAF on modules
Basically as same as above, but in the fprobe-events layer we also
need to get module reference counter when we find the tracepoint in
the module.
* tag 'probes-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: fprobe: Cleanup fprobe hash when module unloading
tracing: fprobe events: Fix possible UAF on modules
tracing: fprobe: Fix to lock module while registering fprobe
Cleanup fprobe address hash table on module unloading because the
target symbols will be disappeared when unloading module and not
sure the same symbol is mapped on the same address.
Note that this is at least disables the fprobes if a part of target
symbols on the unloaded modules. Unlike kprobes, fprobe does not
re-enable the probe point by itself. To do that, the caller should
take care register/unregister fprobe when loading/unloading modules.
This simplifies the fprobe state managememt related to the module
loading/unloading.
Link: https://lore.kernel.org/all/174343534473.843280.13988101014957210732.stgit@devnote2/
Fixes: 4346ba1604 ("fprobe: Rewrite fprobe on function-graph tracer")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
The function get_vm_area() is not defined for non-MMU builds and causes a
build error if it is used. Hide the map_pages() function around a:
#ifdef CONFIG_MMU
to keep it from being compiled when CONFIG_MMU is not set.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250407120111.2ccc9319@gandalf.local.home
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Closes: https://lore.kernel.org/all/4f8ece8b-8862-4f7c-8ede-febd28f8a9fe@roeck-us.net/
Fixes: 394f3f02de ("tracing: Use vmap_page_range() to map memmap ring buffer")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
It was mistaken that the physical memory returned from "reserve_mem" had to
be vmap()'d to get to it from a virtual address. But reserve_mem already
maps the memory to the virtual address of the kernel so a simple
phys_to_virt() can be used to get to the virtual address from the physical
memory returned by "reserve_mem". With this new found knowledge, the
code can be cleaned up and simplified.
- Enforce that the persistent memory is page aligned
As the buffers using the persistent memory are all going to be
mapped via pages, make sure that the memory given to the tracing
infrastructure is page aligned. If it is not, it will print a warning
and fail to map the buffer.
- Use phys_to_virt() to get the virtual address from reserve_mem
Instead of calling vmap() on the physical memory returned from
"reserve_mem", use phys_to_virt() instead.
As the memory returned by "memmap" or any other means where a physical
address is given to the tracing infrastructure, it still needs to
be vmap(). Since this memory can never be returned back to the buddy
allocator nor should it ever be memmory mapped to user space, flag
this buffer and up the ref count. The ref count will keep it from
ever being freed, and the flag will prevent it from ever being memory
mapped to user space.
- Use vmap_page_range() for memmap virtual address mapping
For the memmap buffer, instead of allocating an array of struct pages,
assigning them to the contiguous phsycial memory and then passing that to
vmap(), use vmap_page_range() instead
- Replace flush_dcache_folio() with flush_kernel_vmap_range()
Instead of calling virt_to_folio() and passing that to
flush_dcache_folio(), just call flush_kernel_vmap_range() directly.
This also fixes a bug where if a subbuffer was bigger than PAGE_SIZE
only the PAGE_SIZE portion would be flushed.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ+6oZRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qhq6AP481KHAgaowQCg7zrKPkMlbYBIigYoU
7aqoAg2rSLBRSQEAl8fViHZgZ9Q+O7xdozQWiIR7/KQW8VIaTcP/V7cHkAU=
=+5JB
-----END PGP SIGNATURE-----
Merge tag 'trace-ringbuffer-v6.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ring-buffer updates from Steven Rostedt:
"Persistent buffer cleanups and simplifications.
It was mistaken that the physical memory returned from "reserve_mem"
had to be vmap()'d to get to it from a virtual address. But
reserve_mem already maps the memory to the virtual address of the
kernel so a simple phys_to_virt() can be used to get to the virtual
address from the physical memory returned by "reserve_mem". With this
new found knowledge, the code can be cleaned up and simplified.
- Enforce that the persistent memory is page aligned
As the buffers using the persistent memory are all going to be
mapped via pages, make sure that the memory given to the tracing
infrastructure is page aligned. If it is not, it will print a
warning and fail to map the buffer.
- Use phys_to_virt() to get the virtual address from reserve_mem
Instead of calling vmap() on the physical memory returned from
"reserve_mem", use phys_to_virt() instead.
As the memory returned by "memmap" or any other means where a
physical address is given to the tracing infrastructure, it still
needs to be vmap(). Since this memory can never be returned back to
the buddy allocator nor should it ever be memmory mapped to user
space, flag this buffer and up the ref count. The ref count will
keep it from ever being freed, and the flag will prevent it from
ever being memory mapped to user space.
- Use vmap_page_range() for memmap virtual address mapping
For the memmap buffer, instead of allocating an array of struct
pages, assigning them to the contiguous phsycial memory and then
passing that to vmap(), use vmap_page_range() instead
- Replace flush_dcache_folio() with flush_kernel_vmap_range()
Instead of calling virt_to_folio() and passing that to
flush_dcache_folio(), just call flush_kernel_vmap_range() directly.
This also fixes a bug where if a subbuffer was bigger than
PAGE_SIZE only the PAGE_SIZE portion would be flushed"
* tag 'trace-ringbuffer-v6.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Use flush_kernel_vmap_range() over flush_dcache_folio()
tracing: Use vmap_page_range() to map memmap ring buffer
tracing: Have reserve_mem use phys_to_virt() and separate from memmap buffer
tracing: Enforce the persistent ring buffer to be page aligned
- Fix build error when CONFIG_PROBE_EVENTS_BTF_ARGS is not enabled
The tracing of arguments in the function tracer depends on some
functions that are only defined when PROBE_EVENTS_BTF_ARGS is enabled.
In fact, PROBE_EVENTS_BTF_ARGS also depends on all the same configs
as the function argument tracing requires. Just have the function
argument tracing depend on PROBE_EVENTS_BTF_ARGS.
- Free module_delta for persistent ring buffer instance
When an instance holds the persistent ring buffer, it allocates
a helper array to hold the deltas between where modules are loaded
on the last boot and the current boot. This array needs to be freed
when the instance is freed.
- Add cond_resched() to loop in ftrace_graph_set_hash()
The hash functions in ftrace loop over every function that can be
enabled by ftrace. This can be 50,000 functions or more. This
loop is known to trigger soft lockup warnings and requires a
cond_resched(). The loop in ftrace_graph_set_hash() was missing it.
- Fix the event format verifier to include "%*p.." arguments
To prevent events from dereferencing stale pointers that can
happen if a trace event uses a dereferece pointer to something
that was not copied into the ring buffer and can be freed by the
time the trace is read, a verifier is called. At boot or module
load, the verifier scans the print format string for pointers
that can be dereferenced and it checks the arguments to make sure
they do not contain something that can be freed. The "%*p" was
not handled, which would add another argument and cause the verifier
to not only not verify this pointer, but it will look at the wrong
argument for every pointer after that.
- Fix mcount sorttable building for different endian type target
When modifying the ELF file to sort the mcount_loc table in the
sorttable.c code, the endianess of the file and the host is used
to determine if the bytes need to be swapped when calculations are
done. A change was made to the sorting of the mcount_loc that read
the values from the ELF file into an array and the swap happened
on the filling of the array. But one of the calculations of the
array still did the swap when it did not need to. This caused building
on a little endian machine for a big endian target to not find
the mcount function in the 'nm' table and it zeroed it out, causing
there to be no functions available to trace.
- Add goto out_unlock jump to rv_register_monitor() on error path
One of the error paths in rv_register_monitor() just returned the
error when it should have jumped to the out_unlock label to release
the mutex.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ+2tyBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qjPYAPwJDti6nHTqheFwIa1WzJ3yC2tKRYKt
1E5PYW/2Ct5NmwEAqgg3TvJppXHymVdutLghhGFnlBnyTWMI+KIhparSBw8=
=NFM5
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix build error when CONFIG_PROBE_EVENTS_BTF_ARGS is not enabled
The tracing of arguments in the function tracer depends on some
functions that are only defined when PROBE_EVENTS_BTF_ARGS is
enabled. In fact, PROBE_EVENTS_BTF_ARGS also depends on all the same
configs as the function argument tracing requires. Just have the
function argument tracing depend on PROBE_EVENTS_BTF_ARGS.
- Free module_delta for persistent ring buffer instance
When an instance holds the persistent ring buffer, it allocates a
helper array to hold the deltas between where modules are loaded on
the last boot and the current boot. This array needs to be freed when
the instance is freed.
- Add cond_resched() to loop in ftrace_graph_set_hash()
The hash functions in ftrace loop over every function that can be
enabled by ftrace. This can be 50,000 functions or more. This loop is
known to trigger soft lockup warnings and requires a cond_resched().
The loop in ftrace_graph_set_hash() was missing it.
- Fix the event format verifier to include "%*p.." arguments
To prevent events from dereferencing stale pointers that can happen
if a trace event uses a dereferece pointer to something that was not
copied into the ring buffer and can be freed by the time the trace is
read, a verifier is called. At boot or module load, the verifier
scans the print format string for pointers that can be dereferenced
and it checks the arguments to make sure they do not contain
something that can be freed. The "%*p" was not handled, which would
add another argument and cause the verifier to not only not verify
this pointer, but it will look at the wrong argument for every
pointer after that.
- Fix mcount sorttable building for different endian type target
When modifying the ELF file to sort the mcount_loc table in the
sorttable.c code, the endianess of the file and the host is used to
determine if the bytes need to be swapped when calculations are done.
A change was made to the sorting of the mcount_loc that read the
values from the ELF file into an array and the swap happened on the
filling of the array. But one of the calculations of the array still
did the swap when it did not need to. This caused building on a
little endian machine for a big endian target to not find the mcount
function in the 'nm' table and it zeroed it out, causing there to be
no functions available to trace.
- Add goto out_unlock jump to rv_register_monitor() on error path
One of the error paths in rv_register_monitor() just returned the
error when it should have jumped to the out_unlock label to release
the mutex.
* tag 'trace-v6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
rv: Fix missing unlock on double nested monitors return path
scripts/sorttable: Fix endianness handling in build-time mcount sort
tracing: Verify event formats that have "%*p.."
ftrace: Add cond_resched() to ftrace_graph_set_hash()
tracing: Free module_delta on freeing of persistent ring buffer
ftrace: Have tracing function args depend on PROBE_EVENTS_BTF_ARGS
-----BEGIN PGP SIGNATURE-----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=Biv4
-----END PGP SIGNATURE-----
Merge tag 'printk-for-6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull more printk updates from Petr Mladek:
- Silence warnings about candidates for ‘gnu_print’ format attribute
* tag 'printk-for-6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
vsnprintf: Silence false positive GCC warning for va_format()
vsnprintf: Drop unused const char fmt * in va_format()
vsnprintf: Mark binary printing functions with __printf() attribute
tracing: Mark binary printing functions with __printf() attribute
seq_file: Mark binary printing functions with __printf() attribute
seq_buf: Mark binary printing functions with __printf() attribute
Some architectures do not have data cache coherency between user and
kernel space. For these architectures, the cache needs to be flushed on
both the kernel and user addresses so that user space can see the updates
the kernel has made.
Instead of using flush_dcache_folio() and playing with virt_to_folio()
within the call to that function, use flush_kernel_vmap_range() which
takes the virtual address and does the work for those architectures that
need it.
This also fixes a bug where the flush of the reader page only flushed one
page. If the sub-buffer order is 1 or more, where the sub-buffer size
would be greater than a page, it would miss the rest of the sub-buffer
content, as the "reader page" is not just a page, but the size of a
sub-buffer.
Link: https://lore.kernel.org/all/CAG48ez3w0my4Rwttbc5tEbNsme6tc0mrSN95thjXUFaJ3aQ6SA@mail.gmail.com/
Cc: stable@vger.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Rapoport <rppt@kernel.org>
Link: https://lore.kernel.org/20250402144953.920792197@goodmis.org
Fixes: 117c39200d ("ring-buffer: Introducing ring-buffer mapping functions");
Suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The code to map the physical memory retrieved by memmap currently
allocates an array of pages to cover the physical memory and then calls
vmap() to map it to a virtual address. Instead of using this temporary
array of struct page descriptors, simply use vmap_page_range() that can
directly map the contiguous physical memory to a virtual address.
Link: https://lore.kernel.org/all/CAHk-=whUOfVucfJRt7E0AH+GV41ELmS4wJqxHDnui6Giddfkzw@mail.gmail.com/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/20250402144953.754618481@goodmis.org
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The reserve_mem kernel command line option may pass back a physical
address, but the memory is still part of the normal memory just like
using memblock_alloc() would be. This means that the physical memory
returned by the reserve_mem command line option can be converted directly
to virtual memory by simply using phys_to_virt().
When freeing the buffer there's no need to call vunmap() anymore as the
memory allocated by reserve_mem is freed by the call to
reserve_mem_release_by_name().
Because the persistent ring buffer can also be allocated via the memmap
option, which *is* different than normal memory as it cannot be added back
to the buddy system, it must be treated differently. It still needs to be
virtually mapped to have access to it. It also can not be freed nor can it
ever be memory mapped to user space.
Create a new trace_array flag called TRACE_ARRAY_FL_MEMMAP which gets set
if the buffer is created by the memmap option, and this will prevent the
buffer from being memory mapped by user space.
Also increment the ref count for memmap'ed buffers so that they can never
be freed.
Link: https://lore.kernel.org/all/Z-wFszhJ_9o4dc8O@kernel.org/
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/20250402144953.583750106@goodmis.org
Suggested-by: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Enforce that the address and the size of the memory used by the persistent
ring buffer is page aligned. Also update the documentation to reflect this
requirement.
Link: https://lore.kernel.org/all/CAHk-=whUOfVucfJRt7E0AH+GV41ELmS4wJqxHDnui6Giddfkzw@mail.gmail.com/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/20250402144953.412882844@goodmis.org
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Commit ac91052f0a ("tracing: tprobe-events: Fix leakage of module
refcount") moved try_module_get() from __find_tracepoint_module_cb()
to find_tracepoint() caller, but that introduced a possible UAF
because the module can be unloaded before try_module_get(). In this
case, the module object should be freed too. Thus, try_module_get()
does not only fail but may access to the freed object.
To avoid that, try_module_get() in __find_tracepoint_module_cb()
again.
Link: https://lore.kernel.org/all/174342990779.781946.9138388479067729366.stgit@devnote2/
Fixes: ac91052f0a ("tracing: tprobe-events: Fix leakage of module refcount")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
RV doesn't support nested monitors having children monitors themselves
and exits with the EINVAL code. However, it returns without unlocking
the rv_interface_lock.
Unlock the lock before returning from the initialisation function.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/20250402071351.19864-2-gmonaco@redhat.com
Fixes: cb85c660fc ("rv: Add option for nested monitors and include sched")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Julia Lawall <julia.lawall@inria.fr>
Closes: https://lore.kernel.org/r/202503310200.UBXGitB4-lkp@intel.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The trace event verifier checks the formats of trace events to make sure
that they do not point at memory that is not in the trace event itself or
in data that will never be freed. If an event references data that was
allocated when the event triggered and that same data is freed before the
event is read, then the kernel can crash by reading freed memory.
The verifier runs at boot up (or module load) and scans the print formats
of the events and checks their arguments to make sure that dereferenced
pointers are safe. If the format uses "%*p.." the verifier will ignore it,
and that could be dangerous. Cover this case as well.
Also add to the sample code a use case of "%*pbl".
Link: https://lore.kernel.org/all/bcba4d76-2c3f-4d11-baf0-02905db953dd@oracle.com/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 5013f454a3 ("tracing: Add check of trace event print fmts for dereferencing pointers")
Link: https://lore.kernel.org/20250327195311.2d89ec66@gandalf.local.home
Reported-by: Libo Chen <libo.chen@oracle.com>
Reviewed-by: Libo Chen <libo.chen@oracle.com>
Tested-by: Libo Chen <libo.chen@oracle.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the kernel contains a large number of functions that can be traced,
the loop in ftrace_graph_set_hash() may take a lot of time to execute.
This may trigger the softlockup watchdog.
Add cond_resched() within the loop to allow the kernel to remain
responsive even when processing a large number of functions.
This matches the cond_resched() that is used in other locations of the
code that iterates over all functions that can be traced.
Cc: stable@vger.kernel.org
Fixes: b9b0c831be ("ftrace: Convert graph filter to use hash tables")
Link: https://lore.kernel.org/tencent_3E06CE338692017B5809534B9C5C03DA7705@qq.com
Signed-off-by: zhoumin <teczm@foxmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
If a persistent ring buffer is created, a "module_delta" array is also
allocated to hold the module deltas of loaded modules that match modules
in the scratch area. If this buffer gets freed, the module_delta array is
not freed and causes a memory leak.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250401124525.1f9ac02a@gandalf.local.home
Fixes: 35a380ddbc ("tracing: Show last module text symbols in the stacktrace")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The option PROBE_EVENTS_BTF_ARGS enables the functions
btf_find_func_proto() and btf_get_func_param() which are used by the
function argument tracing code. The option FUNCTION_TRACE_ARGS was
dependent on the same configs that PROBE_EVENTS_BTF_ARGS was dependent on,
but it was also dependent on PROBE_EVENTS_BTF_ARGS. In fact, if
PROBE_EVENTS_BTF_ARGS is supported then FUNCTION_TRACE_ARGS is supported.
Just make FUNCTION_TRACE_ARGS depend on PROBE_EVENTS_BTF_ARGS.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/20250401113601.17fa1129@gandalf.local.home
Fixes: 533c20b062 ("ftrace: Add print_function_args()")
Closes: https://lore.kernel.org/all/DB9PR08MB75820599801BAD118D123D7D93AD2@DB9PR08MB7582.eurprd08.prod.outlook.com/
Reported-by: Christian Loehle <Christian.Loehle@arm.com>
Tested-by: Christian Loehle <Christian.Loehle@arm.com>
Tested-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Restructure the persistent memory to have a "scratch" area
Instead of hard coding the KASLR offset in the persistent memory
by the ring buffer, push that work up to the callers of the persistent
memory as they are the ones that need this information. The offsets
and such is not important to the ring buffer logic and it should
not be part of that.
A scratch pad is now created when the caller allocates a ring buffer
from persistent memory by stating how much memory it needs to save.
- Allow where modules are loaded to be saved in the new scratch pad
Save the addresses of modules when they are loaded into the persistent
memory scratch pad.
- A new module_for_each_mod() helper function was created
With the acknowledgement of the module maintainers a new module helper
function was created to iterate over all the currently loaded modules.
This has a callback to be called for each module. This is needed for
when tracing is started in the persistent buffer and the currently loaded
modules need to be saved in the scratch area.
- Expose the last boot information where the kernel and modules were loaded
The last_boot_info file is updated to print out the addresses of where
the kernel "_text" location was loaded from a previous boot, as well
as where the modules are loaded. If the buffer is recording the current
boot, it only prints "# Current" so that it does not expose the KASLR
offset of the currently running kernel.
- Allow the persistent ring buffer to be released (freed)
To have this in production environments, where the kernel command line can
not be changed easily, the ring buffer needs to be freed when it is not
going to be used. The memory for the buffer will always be allocated at
boot up, but if the system isn't going to enable tracing, the memory needs
to be freed. Allow it to be freed and added back to the kernel memory
pool.
- Allow stack traces to print the function names in the persistent buffer
Now that the modules are saved in the persistent ring buffer, if the same
modules are loaded, the printing of the function names will examine the
saved modules. If the module is found in the scratch area and is also
loaded, then it will do the offset shift and use kallsyms to display the
function name. If the address is not found, it simply displays the address
from the previous boot in hex.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ+cUERQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qrAsAQCFt2nfzxoe3wtF5EqIT1VHp/8bQVjG
gBe8B6ouboreogD/dS7yK8MRy24ZAmObGwYG0RbVicd50S7P8Rf7+823ng8=
=OJKk
-----END PGP SIGNATURE-----
Merge tag 'trace-ringbuffer-v6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ring-buffer updates from Steven Rostedt:
- Restructure the persistent memory to have a "scratch" area
Instead of hard coding the KASLR offset in the persistent memory by
the ring buffer, push that work up to the callers of the persistent
memory as they are the ones that need this information. The offsets
and such is not important to the ring buffer logic and it should not
be part of that.
A scratch pad is now created when the caller allocates a ring buffer
from persistent memory by stating how much memory it needs to save.
- Allow where modules are loaded to be saved in the new scratch pad
Save the addresses of modules when they are loaded into the
persistent memory scratch pad.
- A new module_for_each_mod() helper function was created
With the acknowledgement of the module maintainers a new module
helper function was created to iterate over all the currently loaded
modules. This has a callback to be called for each module. This is
needed for when tracing is started in the persistent buffer and the
currently loaded modules need to be saved in the scratch area.
- Expose the last boot information where the kernel and modules were
loaded
The last_boot_info file is updated to print out the addresses of
where the kernel "_text" location was loaded from a previous boot, as
well as where the modules are loaded. If the buffer is recording the
current boot, it only prints "# Current" so that it does not expose
the KASLR offset of the currently running kernel.
- Allow the persistent ring buffer to be released (freed)
To have this in production environments, where the kernel command
line can not be changed easily, the ring buffer needs to be freed
when it is not going to be used. The memory for the buffer will
always be allocated at boot up, but if the system isn't going to
enable tracing, the memory needs to be freed. Allow it to be freed
and added back to the kernel memory pool.
- Allow stack traces to print the function names in the persistent
buffer
Now that the modules are saved in the persistent ring buffer, if the
same modules are loaded, the printing of the function names will
examine the saved modules. If the module is found in the scratch area
and is also loaded, then it will do the offset shift and use kallsyms
to display the function name. If the address is not found, it simply
displays the address from the previous boot in hex.
* tag 'trace-ringbuffer-v6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Use _text and the kernel offset in last_boot_info
tracing: Show last module text symbols in the stacktrace
ring-buffer: Remove the unused variable bmeta
tracing: Skip update_last_data() if cleared and remove active check for save_mod()
tracing: Initialize scratch_size to zero to prevent UB
tracing: Fix a compilation error without CONFIG_MODULES
tracing: Freeable reserved ring buffer
mm/memblock: Add reserved memory release function
tracing: Update modules to persistent instances when loaded
tracing: Show module names and addresses of last boot
tracing: Have persistent trace instances save module addresses
module: Add module_for_each_mod() function
tracing: Have persistent trace instances save KASLR offset
ring-buffer: Add ring_buffer_meta_scratch()
ring-buffer: Add buffer meta data for persistent ring buffer
ring-buffer: Use kaslr address instead of text delta
ring-buffer: Fix bytes_dropped calculation issue
- Use RCU instead of RCU-sched
The mix of rcu_read_lock(), rcu_read_lock_sched() and preempt_disable()
in the module code and its users has been replaced with just
rcu_read_lock().
- The rest of changes are smaller fixes and updates.
The changes have been on linux-next for at least 2 weeks, with the RCU
cleanup present for 2 months. One performance problem was reported with the
RCU change when KASAN + lockdep were enabled, but it was effectively
addressed by the already merged ee57ab5a32 ("locking/lockdep: Disable
KASAN instrumentation of lockdep.c").
-----BEGIN PGP SIGNATURE-----
iQFIBAABCAAyFiEEIduBR9MnFA82q/jtumpXJwqY6poFAmfmwrsUHHBldHIucGF2
bHVAc3VzZS5jb20ACgkQumpXJwqY6prWxgf/S7Pvdywm10vJ6fooYa+GxXNMwhyh
XRjZ4m9gjeTNf2KLwX0XHv0XZeFHOmHfjd3iI+pS6CXZnCFTN9J3XPLYsrTxXUb6
U6zzLf8Zsz8TzeI4dgvSBsZln7oICSACkAgdJCq23hpNKeaeRo91dgiZaIwyZJG3
FekqSFtP7pYhfFoNkrFKysqbgl1+RWWZ79L2qRJA0bPzVFlvRUuh6cOHQw+8RMqf
BYLwnArjTkW8AcXpxIXSiwphDHVZ81B96xoplavyoprA5FDpv1W+8y4DtxdWFn+1
QVWCs/ZV3KrwXWpZev625w3fIOOIXILqRINOzLfvXTw+1xFS3TzSQEpVeg==
=4OKc
-----END PGP SIGNATURE-----
Merge tag 'modules-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux
Pull modules updates from Petr Pavlu:
- Use RCU instead of RCU-sched
The mix of rcu_read_lock(), rcu_read_lock_sched() and
preempt_disable() in the module code and its users has
been replaced with just rcu_read_lock()
- The rest of changes are smaller fixes and updates
* tag 'modules-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux: (32 commits)
MAINTAINERS: Update the MODULE SUPPORT section
module: Remove unnecessary size argument when calling strscpy()
module: Replace deprecated strncpy() with strscpy()
params: Annotate struct module_param_attrs with __counted_by()
bug: Use RCU instead RCU-sched to protect module_bug_list.
static_call: Use RCU in all users of __module_text_address().
kprobes: Use RCU in all users of __module_text_address().
bpf: Use RCU in all users of __module_text_address().
jump_label: Use RCU in all users of __module_text_address().
jump_label: Use RCU in all users of __module_address().
x86: Use RCU in all users of __module_address().
cfi: Use RCU while invoking __module_address().
powerpc/ftrace: Use RCU in all users of __module_text_address().
LoongArch: ftrace: Use RCU in all users of __module_text_address().
LoongArch/orc: Use RCU in all users of __module_address().
arm64: module: Use RCU in all users of __module_text_address().
ARM: module: Use RCU in all users of __module_text_address().
module: Use RCU in all users of __module_text_address().
module: Use RCU in all users of __module_address().
module: Use RCU in search_module_extables().
...
-----BEGIN PGP SIGNATURE-----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=aN/V
-----END PGP SIGNATURE-----
Merge tag 'bpf-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
"For this merge window we're splitting BPF pull request into three for
higher visibility: main changes, res_spin_lock, try_alloc_pages.
These are the main BPF changes:
- Add DFA-based live registers analysis to improve verification of
programs with loops (Eduard Zingerman)
- Introduce load_acquire and store_release BPF instructions and add
x86, arm64 JIT support (Peilin Ye)
- Fix loop detection logic in the verifier (Eduard Zingerman)
- Drop unnecesary lock in bpf_map_inc_not_zero() (Eric Dumazet)
- Add kfunc for populating cpumask bits (Emil Tsalapatis)
- Convert various shell based tests to selftests/bpf/test_progs
format (Bastien Curutchet)
- Allow passing referenced kptrs into struct_ops callbacks (Amery
Hung)
- Add a flag to LSM bpf hook to facilitate bpf program signing
(Blaise Boscaccy)
- Track arena arguments in kfuncs (Ihor Solodrai)
- Add copy_remote_vm_str() helper for reading strings from remote VM
and bpf_copy_from_user_task_str() kfunc (Jordan Rome)
- Add support for timed may_goto instruction (Kumar Kartikeya
Dwivedi)
- Allow bpf_get_netns_cookie() int cgroup_skb programs (Mahe Tardy)
- Reduce bpf_cgrp_storage_busy false positives when accessing cgroup
local storage (Martin KaFai Lau)
- Introduce bpf_dynptr_copy() kfunc (Mykyta Yatsenko)
- Allow retrieving BTF data with BTF token (Mykyta Yatsenko)
- Add BPF kfuncs to set and get xattrs with 'security.bpf.' prefix
(Song Liu)
- Reject attaching programs to noreturn functions (Yafang Shao)
- Introduce pre-order traversal of cgroup bpf programs (Yonghong
Song)"
* tag 'bpf-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (186 commits)
selftests/bpf: Add selftests for load-acquire/store-release when register number is invalid
bpf: Fix out-of-bounds read in check_atomic_load/store()
libbpf: Add namespace for errstr making it libbpf_errstr
bpf: Add struct_ops context information to struct bpf_prog_aux
selftests/bpf: Sanitize pointer prior fclose()
selftests/bpf: Migrate test_xdp_vlan.sh into test_progs
selftests/bpf: test_xdp_vlan: Rename BPF sections
bpf: clarify a misleading verifier error message
selftests/bpf: Add selftest for attaching fexit to __noreturn functions
bpf: Reject attaching fexit/fmod_ret to __noreturn functions
bpf: Only fails the busy counter check in bpf_cgrp_storage_get if it creates storage
bpf: Make perf_event_read_output accessible in all program types.
bpftool: Using the right format specifiers
bpftool: Add -Wformat-signedness flag to detect format errors
selftests/bpf: Test freplace from user namespace
libbpf: Pass BPF token from find_prog_btf_id to BPF_BTF_GET_FD_BY_ID
bpf: Return prog btf_id without capable check
bpf: BPF token support for BPF_BTF_GET_FD_BY_ID
bpf, x86: Fix objtool warning for timed may_goto
bpf: Check map->record at the beginning of check_and_free_fields()
...
Instead of using kaslr_offset() just record the location of "_text". This
makes it possible for user space to use either the System.map or
/proc/kallsyms as what to map all addresses to functions with.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250326220304.38dbedcd@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Since the previous boot trace buffer can include module text address in
the stacktrace. As same as the kernel text address, convert the module
text address using the module address information.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/174282689201.356346.17647540360450727687.stgit@mhiramat.tok.corp.google.com
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
If the last boot data is already cleared, there is no reason to update it
again. Skip if the TRACE_ARRAY_FL_LAST_BOOT is cleared.
Also, for calling save_mod() when module loading, we don't need to check
the trace is active or not because any module address can be on the
stacktrace.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/174165660328.1173316.15529357882704817499.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In allocate_trace_buffer() the following code:
buf->buffer = ring_buffer_alloc_range(size, rb_flags, 0,
tr->range_addr_start,
tr->range_addr_size,
struct_size(tscratch, entries, 128));
tscratch = ring_buffer_meta_scratch(buf->buffer, &scratch_size);
setup_trace_scratch(tr, tscratch, scratch_size);
Has undefined behavior if ring_buffer_alloc_range() fails because
"scratch_size" is not initialize. If the allocation fails, then
buf->buffer will be NULL. The ring_buffer_meta_scratch() will return
NULL immediately if it is passed a NULL buffer and it will not update
scratch_size. Then setup_trace_scratch() will return immediately if
tscratch is NULL.
Although there's no real issue here, but it is considered undefined
behavior to pass an uninitialized variable to a function as input, and
UBSan may complain about it.
Just initialize scratch_size to zero to make the code defined behavior and
a little more robust.
Link: https://lore.kernel.org/all/44c5deaa-b094-4852-90f9-52f3fb10e67a@stanley.mountain/
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are some code which depends on CONFIG_MODULES. #ifdef
to enclose it.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/174230515367.2909896.8132122175220657625.stgit@mhiramat.tok.corp.google.com
Fixes: dca91c1c5468 ("tracing: Have persistent trace instances save module addresses")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Make the ring buffer on reserved memory to be freeable. This allows us
to free the trace instance on the reserved memory without changing
cmdline and rebooting. Even if we can not change the kernel cmdline
for security reason, we can release the reserved memory for the ring
buffer as free (available) memory.
For example, boot kernel with reserved memory;
"reserve_mem=20M:2M:trace trace_instance=boot_mapped^traceoff@trace"
~ # free
total used free shared buff/cache available
Mem: 1995548 50544 1927568 14964 17436 1911480
Swap: 0 0 0
~ # rmdir /sys/kernel/tracing/instances/boot_mapped/
[ 23.704023] Freeing reserve_mem:trace memory: 20476K
~ # free
total used free shared buff/cache available
Mem: 2016024 41844 1956740 14968 17440 1940572
Swap: 0 0 0
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mike Rapoport <rppt@kernel.org>
Link: https://lore.kernel.org/173989134814.230693.18199312930337815629.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When a module is loaded and a persistent buffer is actively tracing, add
it to the list of modules in the persistent memory.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250305164609.469844721@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add the last boot module's names and addresses to the last_boot_info file.
This only shows the module information from a previous boot. If the buffer
is started and is recording the current boot, this file still will only
show "current".
~# cat instances/boot_mapped/last_boot_info
10c00000 [kernel]
ffffffffc00ca000 usb_serial_simple
ffffffffc00ae000 usbserial
ffffffffc008b000 bfq
~# echo function > instances/boot_mapped/current_tracer
~# cat instances/boot_mapped/last_boot_info
# Current
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250305164609.299186021@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
For trace instances that are mapped to persistent memory, have them use
the scratch area to save the currently loaded modules. This will allow
where the modules have been loaded on the next boot so that their
addresses can be deciphered by using where they were loaded previously.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250305164609.129741650@goodmis.org
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There's no reason to save the KASLR offset for the ring buffer itself.
That is used by the tracer. Now that the tracer has a way to save data in
the persistent memory of the ring buffer, have the tracing infrastructure
take care of the saving of the KASLR offset.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250305164608.792722274@goodmis.org
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Now that there's one meta data at the start of the persistent memory used by
the ring buffer, allow the caller to request some memory right after that
data that it can use as its own persistent memory.
Also fix some white space issues with ring_buffer_alloc().
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250305164608.619631731@goodmis.org
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Instead of just having a meta data at the first page of each sub buffer
that has duplicate data, add a new meta page to the entire block of memory
that holds the duplicate data and remove it from the sub buffer meta data.
This will open up the extra memory in this first page to be used by the
tracer for its own persistent data.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250305164608.446351513@goodmis.org
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Instead of saving off the text and data pointers and using them to compare
with the current boot's text and data pointers, just save off the KASLR
offset. Then that can be used to figure out how to read the previous boots
buffer.
The last_boot_info will now show this offset, but only if it is for a
previous boot:
~# cat instances/boot_mapped/last_boot_info
39000000 [kernel]
~# echo function > instances/boot_mapped/current_tracer
~# cat instances/boot_mapped/last_boot_info
# Current
If the KASLR offset saved is for the current boot, the last_boot_info will
show the value of "current".
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250305164608.274956504@goodmis.org
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The calculation of bytes-dropped and bytes_dropped_nested is reversed.
Although it does not affect the final calculation of total_dropped,
it should still be modified.
Link: https://lore.kernel.org/20250223070106.6781-1-yangfeng59949@163.com
Fixes: 6c43e554a2 ("ring-buffer: Add ring buffer startup selftest")
Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Binary printing functions are using printf() type of format, and compiler
is not happy about them as is:
kernel/trace/trace.c:3292:9: error: function ‘trace_vbprintk’ might be a candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format]
kernel/trace/trace_seq.c:182:9: error: function ‘trace_seq_bprintf’ might be a candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format]
Fix the compilation errors by adding __printf() attribute.
While at it, move existing __printf() attributes from the implementations
to the declarations. IT also fixes incorrect attribute parameters that are
used for trace_array_printk().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250321144822.324050-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
- probe-events: Add comments about entry data storing code to clarify
where and how the entry data is stored for function return events.
- probe-events: Log error for exceeding the number of arguments to help
user to identify error reason via tracefs/error_log file.
- selftests/ftrace: Improve the ftracetest to add followngs.
. Expand the tprobe event test to check if it can correctly find
the wrong format tracepoint name.
. Add new syntax error test to check whether error_log correctly
indicates a wrong character in the tracepoint name.
. Add a new dynamic events argument limitation test case which checks
max number of probe arguments.
-----BEGIN PGP SIGNATURE-----
iQFPBAABCgA5FiEEh7BulGwFlgAOi5DV2/sHvwUrPxsFAmflTlobHG1hc2FtaS5o
aXJhbWF0c3VAZ21haWwuY29tAAoJENv7B78FKz8ba9UIALzzZQxzUhJYO/B/XaCz
KTuSrU2594cLr3nCrmCfL3UHUCr5IcjXKCfUdrgzE9mckWF+nVRXWwbp29KpOQky
fzU9Ardbr7ksGAYFk4My+P/BeYa7vh9LwofXzWlJibANVxWvq66+GfKnWnh1P8Bl
/zjov61DAEQmDfXNGZ2oTmKnYYMoPkJU4voRvAEUgiP02SrF04UUa00uC7hmZJJV
aI5b6TatE5FDEmAoHWh0cf04HoyevRyLVOQd5GSswH/oWpyhs90M7a9WENHamBx6
RXEZ3xYyuH9zBSvYVeRn2H1eHnGCR4RMctZiRGXF8EdLWo7RXRQ1Hp9CgvwDrU8Z
IL0=
=vZ3e
-----END PGP SIGNATURE-----
Merge tag 'probes-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes updates from Masami Hiramatsu:
- probe-events: Add comments about entry data storing code to clarify
where and how the entry data is stored for function return events.
- probe-events: Log error for exceeding the number of arguments to help
user to identify error reason via tracefs/error_log file.
- Improve the ftracetest selftests:
- Expand the tprobe event test to check if it can correctly find the
wrong format tracepoint name.
- Add new syntax error test to check whether error_log correctly
indicates a wrong character in the tracepoint name.
- Add a new dynamic events argument limitation test case which
checks max number of probe arguments.
* tag 'probes-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: probe-events: Add comments about entry data storing code
selftests/ftrace: Add dynamic events argument limitation test case
selftests/ftrace: Add new syntax error test
selftests/ftrace: Expand the tprobe event test to check wrong format
tracing: probe-events: Log error for exceeding the number of arguments
- Add option traceoff_after_boot
In order to debug kernel boot, it sometimes is helpful to enable tracing
via the kernel command line. Unfortunately, by the time the login prompt
appears, the trace is overwritten by the init process and other user space
start up applications. Adding a "traceoff_after_boot" will disable tracing
when the kernel passes control to init which will allow developers to be
able to see the traces that occurred during boot.
- Clean up the mmflags macros that display the GFP flags in trace events
The macros to print the GFP flags for trace events had a bit of
duplication. The code was restructured to remove duplication and in the
process it also adds some flags that were missed before.
- Removed some dead code and scripts/draw_functrace.py
draw_functrace.py hasn't worked in years and as nobody complained
about it, remove it.
- Constify struct event_trigger_ops
The event_trigger_ops is just a structure that has function pointers that
are assigned when the variables are created. These variables should all be
constants.
- Other minor clean ups and fixes
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ+V9IhQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qr4RAP9JhE3n69pGuOVaJTN/LGLr2Axl59n4
KqZSZS1nUM76/gD6AxYpR7nxyxgJ7VjNkLptS9tSjJVdPDxGAl0v3eO04w4=
=SU30
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing updates from Steven Rostedt:
- Add option traceoff_after_boot
In order to debug kernel boot, it sometimes is helpful to enable
tracing via the kernel command line. Unfortunately, by the time the
login prompt appears, the trace is overwritten by the init process
and other user space start up applications.
Adding a "traceoff_after_boot" will disable tracing when the kernel
passes control to init which will allow developers to be able to see
the traces that occurred during boot.
- Clean up the mmflags macros that display the GFP flags in trace
events
The macros to print the GFP flags for trace events had a bit of
duplication. The code was restructured to remove duplication and in
the process it also adds some flags that were missed before.
- Removed some dead code and scripts/draw_functrace.py
draw_functrace.py hasn't worked in years and as nobody complained
about it, remove it.
- Constify struct event_trigger_ops
The event_trigger_ops is just a structure that has function pointers
that are assigned when the variables are created. These variables
should all be constants.
- Other minor clean ups and fixes
* tag 'trace-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Replace strncpy with memcpy for fixed-length substring copy
tracing: Fix synth event printk format for str fields
tracing: Do not use PERF enums when perf is not defined
tracing: Ensure module defining synth event cannot be unloaded while tracing
tracing: fix return value in __ftrace_event_enable_disable for TRACE_REG_UNREGISTER
tracing/osnoise: Fix possible recursive locking for cpus_read_lock()
tracing: Align synth event print fmt
tracing: gfp: vsprintf: Do not print "none" when using %pGg printf format
tracepoint: Print the function symbol when tracepoint_debug is set
tracing: Constify struct event_trigger_ops
scripts/tracing: Remove scripts/tracing/draw_functrace.py
tracing: Update MAINTAINERS file to include tracepoint.c
tracing/user_events: Slightly simplify user_seq_show()
tracing/user_events: Don't use %pK through printk
tracing: gfp: Remove duplication of recording GFP flags
tracing: Remove orphaned event_trace_printk
ring-buffer: Fix typo in comment about header page pointer
tracing: Add traceoff_after_boot option
- Add some trace events to osnoise and timerlat sample generation
This adds more information to the osnoise and timerlat tracers as well as
allows BPF programs to be attached to these locations to extract even more
data.
- Fix to DECLARE_TRACE_CONDITION() macro
It wasn't used but now will be and it happened to be broken causing the
build to fail.
- Add scheduler specification monitors to runtime verifier (RV)
This is a continuation of Daniel Bristot's work.
RV allows monitors to run and react concurrently. Running the cumulative
model is equivalent to running single components using the same
reactors, with the advantage that it's easier to point out which
specification failed in case of error.
This update introduces nested monitors to RV, in short, the sysfs
monitor folder will contain a monitor named sched, which is nothing but
an empty container for other monitors. Controlling the sched monitor
(enable, disable, set reactors) controls all nested monitors.
The following scheduling monitors are added:
* sco: scheduling context operations
Monitor to ensure sched_set_state happens only in thread context
* tss: task switch while scheduling
Monitor to ensure sched_switch happens only in scheduling context
* snroc: set non runnable on its own context
Monitor to ensure set_state happens only in the respective task's context
* scpd: schedule called with preemption disabled
Monitor to ensure schedule is called with preemption disabled
* snep: schedule does not enable preempt
Monitor to ensure schedule does not enable preempt
* sncid: schedule not called with interrupt disabled
Monitor to ensure schedule is not called with interrupt disabled
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ+QhuxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qg62AP9bkeNDbiCuAqjZGddV09Hw26wC3yum
kQoNSebD8G52rQEA9GDjK37xGzYwW/fJokhJVTV39qfub6inAJE5dS6WeQY=
=8Ikv
-----END PGP SIGNATURE-----
Merge tag 'trace-latency-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull latency tracing updates from Steven Rostedt:
- Add some trace events to osnoise and timerlat sample generation
This adds more information to the osnoise and timerlat tracers as
well as allows BPF programs to be attached to these locations to
extract even more data.
- Fix to DECLARE_TRACE_CONDITION() macro
It wasn't used but now will be and it happened to be broken causing
the build to fail.
- Add scheduler specification monitors to runtime verifier (RV)
This is a continuation of Daniel Bristot's work.
RV allows monitors to run and react concurrently. Running the
cumulative model is equivalent to running single components using the
same reactors, with the advantage that it's easier to point out which
specification failed in case of error.
This update introduces nested monitors to RV, in short, the sysfs
monitor folder will contain a monitor named sched, which is nothing
but an empty container for other monitors. Controlling the sched
monitor (enable, disable, set reactors) controls all nested monitors.
The following scheduling monitors are added:
- sco: scheduling context operations
Monitor to ensure sched_set_state happens only in thread context
- tss: task switch while scheduling
Monitor to ensure sched_switch happens only in scheduling context
- snroc: set non runnable on its own context
Monitor to ensure set_state happens only in the respective task's context
- scpd: schedule called with preemption disabled
Monitor to ensure schedule is called with preemption disabled
- snep: schedule does not enable preempt
Monitor to ensure schedule does not enable preempt
- sncid: schedule not called with interrupt disabled
Monitor to ensure schedule is not called with interrupt disabled
* tag 'trace-latency-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tools/rv: Allow rv list to filter for container
Documentation/rv: Add docs for the sched monitors
verification/dot2k: Add support for nested monitors
tools/rv: Add support for nested monitors
rv: Add scpd, snep and sncid per-cpu monitors
rv: Add snroc per-task monitor
rv: Add sco and tss per-cpu monitors
rv: Add option for nested monitors and include sched
sched: Add sched tracepoints for RV task model
rv: Add license identifiers to monitor files
tracing: Fix DECLARE_TRACE_CONDITION
trace/osnoise: Add trace events for samples
- Record function parameters for function and function graph tracers
An option has been added to function tracer (func-args) and the function
graph tracer (funcgraph-args) that when set, the tracers will record the
registers that hold the arguments into each function event. On reading of
the trace, it will use BTF to print those arguments. Most archs support up
to 6 arguments (depending on the complexity of the arguments) and those
are printed. If a function has more arguments then what was recorded, the
output will end with " ... )".
Example of function graph tracer:
6) | dummy_xmit [dummy](skb = 0x8887c100, dev = 0x872ca000) {
6) | consume_skb(skb = 0x8887c100) {
6) | skb_release_head_state(skb = 0x8887c100) {
6) 0.178 us | sock_wfree(skb = 0x8887c100)
6) 0.627 us | }
- The rest of the changes are minor clean ups and fixes
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ+M9vRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qrBGAP9NTn4Lpci69n8FJGfz+UKUEKbzOOeg
QrkIZIxbm8N56gEA0RaUionWjt1znZXUdBTsE3h+en/Ik0//VZytQcmJBwM=
=fxuG
-----END PGP SIGNATURE-----
Merge tag 'ftrace-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace updates from Steven Rostedt:
- Record function parameters for function and function graph tracers
An option has been added to function tracer (func-args) and the
function graph tracer (funcgraph-args) that when set, the tracers
will record the registers that hold the arguments into each function
event. On reading of the trace, it will use BTF to print those
arguments. Most archs support up to 6 arguments (depending on the
complexity of the arguments) and those are printed.
If a function has more arguments then what was recorded, the output
will end with " ... )".
Example of function graph tracer:
6) | dummy_xmit [dummy](skb = 0x8887c100, dev = 0x872ca000) {
6) | consume_skb(skb = 0x8887c100) {
6) | skb_release_head_state(skb = 0x8887c100) {
6) 0.178 us | sock_wfree(skb = 0x8887c100)
6) 0.627 us | }
- The rest of the changes are minor clean ups and fixes
* tag 'ftrace-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Use hashtable.h for event_hash
tracing: Fix use-after-free in print_graph_function_flags during tracer switching
function_graph: Remove the unused variable func
ftrace: Add arguments to function tracer
ftrace: Have funcgraph-args take affect during tracing
ftrace: Add support for function argument to graph tracer
ftrace: Add print_function_args()
ftrace: Have ftrace_free_filter() WARN and exit if ops is active
fgraph: Correct typo in ftrace_return_to_handler comment
- Implement arm64 build time sorting of the mcount location table
When gcc is used to build arm64, the mcount_loc section is all zeros in
the vmlinux elf file. The addresses are stored in the Elf_Rela location.
To sort at build time, an array is allocated and the addresses are added
to it via the content of the mcount_loc section as well as he Elf_Rela
data. After sorting, the information is put back into the Elf_Rela which
now has the section sorted.
- Make sorting of mcount location table for arm64 work with clang as well
When clang is used, the mcount_loc section contains the addresses, unlike
the gcc build. An array is still created and the sorting works for both
methods.
- Remove weak functions from the mcount_loc section
Have the sorttable code pass in the data of functions defined via nm -S
which shows the functions as well as their sizes. Using this information
the sorttable code can determine if a function in the mcount_loc section
was weak and overridden. If the function is not found, it is set to be
zero. On boot, when the mcount_loc section is read and the ftrace table is
created, if the address in the mcount_loc is not in the kernel core text
then it is removed and not added to the ftrace_filter_functions (the
functions that can be attached by ftrace callbacks).
- Update and fix the reporting of how much data is used for ftrace functions
On boot, a report of how many pages were used by the ftrace table as well
as how they were grouped (the table holds a list of sections that are
groups of pages that were able to be allocated). The removing of the weak
functions required the accounting to be updated.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ+MnThQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qivsAQDhPOCaONai7rvHX9T1aOHGjdajZ7SI
qoZgBOsc2ZUkoQD/U2M/m7Yof9aR4I+VFKtT5NsAwpfqPSOL/t/1j6UEOQ8=
=45AV
-----END PGP SIGNATURE-----
Merge tag 'trace-sorttable-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing / sorttable updates from Steven Rostedt:
- Implement arm64 build time sorting of the mcount location table
When gcc is used to build arm64, the mcount_loc section is all zeros
in the vmlinux elf file. The addresses are stored in the Elf_Rela
location.
To sort at build time, an array is allocated and the addresses are
added to it via the content of the mcount_loc section as well as he
Elf_Rela data. After sorting, the information is put back into the
Elf_Rela which now has the section sorted.
- Make sorting of mcount location table for arm64 work with clang as
well
When clang is used, the mcount_loc section contains the addresses,
unlike the gcc build. An array is still created and the sorting works
for both methods.
- Remove weak functions from the mcount_loc section
Have the sorttable code pass in the data of functions defined via
'nm -S' which shows the functions as well as their sizes. Using this
information the sorttable code can determine if a function in the
mcount_loc section was weak and overridden. If the function is not
found, it is set to be zero. On boot, when the mcount_loc section is
read and the ftrace table is created, if the address in the
mcount_loc is not in the kernel core text then it is removed and not
added to the ftrace_filter_functions (the functions that can be
attached by ftrace callbacks).
- Update and fix the reporting of how much data is used for ftrace
functions
On boot, a report of how many pages were used by the ftrace table as
well as how they were grouped (the table holds a list of sections
that are groups of pages that were able to be allocated). The
removing of the weak functions required the accounting to be updated.
* tag 'trace-sorttable-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
scripts/sorttable: Allow matches to functions before function entry
scripts/sorttable: Use normal sort if theres no relocs in the mcount section
ftrace: Check against is_kernel_text() instead of kaslr_offset()
ftrace: Test mcount_loc addr before calling ftrace_call_addr()
ftrace: Have ftrace pages output reflect freed pages
ftrace: Update the mcount_loc check of skipped entries
scripts/sorttable: Zero out weak functions in mcount_loc table
scripts/sorttable: Always use an array for the mcount_loc sorting
scripts/sorttable: Have mcount rela sort use direct values
arm64: scripts/sorttable: Implement sorting mcount_loc at boot for arm64
-----BEGIN PGP SIGNATURE-----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=oxfV
-----END PGP SIGNATURE-----
Merge tag 'lsm-pr-20250323' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm
Pull lsm updates from Paul Moore:
- Various minor updates to the LSM Rust bindings
Changes include marking trivial Rust bindings as inlines and comment
tweaks to better reflect the LSM hooks.
- Add LSM/SELinux access controls to io_uring_allowed()
Similar to the io_uring_disabled sysctl, add a LSM hook to
io_uring_allowed() to enable LSMs a simple way to enforce security
policy on the use of io_uring. This pull request includes SELinux
support for this new control using the io_uring/allowed permission.
- Remove an unused parameter from the security_perf_event_open() hook
The perf_event_attr struct parameter was not used by any currently
supported LSMs, remove it from the hook.
- Add an explicit MAINTAINERS entry for the credentials code
We've seen problems in the past where patches to the credentials code
sent by non-maintainers would often languish on the lists for
multiple months as there was no one explicitly tasked with the
responsibility of reviewing and/or merging credentials related code.
Considering that most of the code under security/ has a vested
interest in ensuring that the credentials code is well maintained,
I'm volunteering to look after the credentials code and Serge Hallyn
has also volunteered to step up as an official reviewer. I posted the
MAINTAINERS update as a RFC to LKML in hopes that someone else would
jump up with an "I'll do it!", but beyond Serge it was all crickets.
- Update Stephen Smalley's old email address to prevent confusion
This includes a corresponding update to the mailmap file.
* tag 'lsm-pr-20250323' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
mailmap: map Stephen Smalley's old email addresses
lsm: remove old email address for Stephen Smalley
MAINTAINERS: add Serge Hallyn as a credentials reviewer
MAINTAINERS: add an explicit credentials entry
cred,rust: mark Credential methods inline
lsm,rust: reword "destroy" -> "release" in SecurityCtx
lsm,rust: mark SecurityCtx methods inline
perf: Remove unnecessary parameter of security check
lsm: fix a missing security_uring_allowed() prototype
io_uring,lsm,selinux: add LSM hooks for io_uring_setup()
io_uring: refactor io_uring_allowed()
checkpatch.pl reports the following warning:
WARNING: Prefer strscpy, strscpy_pad, or __nonstring over strncpy
(see: https://github.com/KSPP/linux/issues/90)
In synth_field_string_size(), replace strncpy() with memcpy() to copy 'len'
characters from 'start' to 'buf'. The code manually adds a NUL terminator
after the copy, making memcpy safe here.
Link: https://lore.kernel.org/20250325181232.38284-1-siddarthsgml@gmail.com
Signed-off-by: Siddarth G <siddarthsgml@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The printk format for synth event uses "%.*s" to print string fields,
but then only passes the pointer part as var arg.
Replace %.*s with %s as the C string is guaranteed to be null-terminated.
The output in print fmt should never have been updated as __get_str()
handles the string limit because it can access the length of the string in
the string meta data that is saved in the ring buffer.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 8db4d6bfbb ("tracing: Change synthetic event string format to limit printed length")
Link: https://lore.kernel.org/20250325165202.541088-1-douglas.raillard@arm.com
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
hrtimers are initialized with hrtimer_init() and a subsequent store to
the callback pointer. This turned out to be suboptimal for the upcoming
Rust integration and is obviously a silly implementation to begin with.
This cleanup replaces the hrtimer_init(T); T->function = cb; sequence
with hrtimer_setup(T, cb);
The conversion was done with Coccinelle and a few manual fixups.
Once the conversion has completely landed in mainline, hrtimer_init()
will be removed and the hrtimer::function becomes a private member.
-----BEGIN PGP SIGNATURE-----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=bYAX
-----END PGP SIGNATURE-----
Merge tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer cleanups from Thomas Gleixner:
"A treewide hrtimer timer cleanup
hrtimers are initialized with hrtimer_init() and a subsequent store to
the callback pointer. This turned out to be suboptimal for the
upcoming Rust integration and is obviously a silly implementation to
begin with.
This cleanup replaces the hrtimer_init(T); T->function = cb; sequence
with hrtimer_setup(T, cb);
The conversion was done with Coccinelle and a few manual fixups.
Once the conversion has completely landed in mainline, hrtimer_init()
will be removed and the hrtimer::function becomes a private member"
* tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits)
wifi: rt2x00: Switch to use hrtimer_update_function()
io_uring: Use helper function hrtimer_update_function()
serial: xilinx_uartps: Use helper function hrtimer_update_function()
ASoC: fsl: imx-pcm-fiq: Switch to use hrtimer_setup()
RDMA: Switch to use hrtimer_setup()
virtio: mem: Switch to use hrtimer_setup()
drm/vmwgfx: Switch to use hrtimer_setup()
drm/xe/oa: Switch to use hrtimer_setup()
drm/vkms: Switch to use hrtimer_setup()
drm/msm: Switch to use hrtimer_setup()
drm/i915/request: Switch to use hrtimer_setup()
drm/i915/uncore: Switch to use hrtimer_setup()
drm/i915/pmu: Switch to use hrtimer_setup()
drm/i915/perf: Switch to use hrtimer_setup()
drm/i915/gvt: Switch to use hrtimer_setup()
drm/i915/huc: Switch to use hrtimer_setup()
drm/amdgpu: Switch to use hrtimer_setup()
stm class: heartbeat: Switch to use hrtimer_setup()
i2c: Switch to use hrtimer_setup()
iio: Switch to use hrtimer_setup()
...
two locking commits in the locking tree,
part of the locking-core-2025-03-22 pull request. ]
x86 CPU features support:
- Generate the <asm/cpufeaturemasks.h> header based on build config
(H. Peter Anvin, Xin Li)
- x86 CPUID parsing updates and fixes (Ahmed S. Darwish)
- Introduce the 'setcpuid=' boot parameter (Brendan Jackman)
- Enable modifying CPU bug flags with '{clear,set}puid='
(Brendan Jackman)
- Utilize CPU-type for CPU matching (Pawan Gupta)
- Warn about unmet CPU feature dependencies (Sohil Mehta)
- Prepare for new Intel Family numbers (Sohil Mehta)
Percpu code:
- Standardize & reorganize the x86 percpu layout and
related cleanups (Brian Gerst)
- Convert the stackprotector canary to a regular percpu
variable (Brian Gerst)
- Add a percpu subsection for cache hot data (Brian Gerst)
- Unify __pcpu_op{1,2}_N() macros to __pcpu_op_N() (Uros Bizjak)
- Construct __percpu_seg_override from __percpu_seg (Uros Bizjak)
MM:
- Add support for broadcast TLB invalidation using AMD's INVLPGB instruction
(Rik van Riel)
- Rework ROX cache to avoid writable copy (Mike Rapoport)
- PAT: restore large ROX pages after fragmentation
(Kirill A. Shutemov, Mike Rapoport)
- Make memremap(MEMREMAP_WB) map memory as encrypted by default
(Kirill A. Shutemov)
- Robustify page table initialization (Kirill A. Shutemov)
- Fix flush_tlb_range() when used for zapping normal PMDs (Jann Horn)
- Clear _PAGE_DIRTY for kernel mappings when we clear _PAGE_RW
(Matthew Wilcox)
KASLR:
- x86/kaslr: Reduce KASLR entropy on most x86 systems,
to support PCI BAR space beyond the 10TiB region
(CONFIG_PCI_P2PDMA=y) (Balbir Singh)
CPU bugs:
- Implement FineIBT-BHI mitigation (Peter Zijlstra)
- speculation: Simplify and make CALL_NOSPEC consistent (Pawan Gupta)
- speculation: Add a conditional CS prefix to CALL_NOSPEC (Pawan Gupta)
- RFDS: Exclude P-only parts from the RFDS affected list (Pawan Gupta)
System calls:
- Break up entry/common.c (Brian Gerst)
- Move sysctls into arch/x86 (Joel Granados)
Intel LAM support updates: (Maciej Wieczor-Retman)
- selftests/lam: Move cpu_has_la57() to use cpuinfo flag
- selftests/lam: Skip test if LAM is disabled
- selftests/lam: Test get_user() LAM pointer handling
AMD SMN access updates:
- Add SMN offsets to exclusive region access (Mario Limonciello)
- Add support for debugfs access to SMN registers (Mario Limonciello)
- Have HSMP use SMN through AMD_NODE (Yazen Ghannam)
Power management updates: (Patryk Wlazlyn)
- Allow calling mwait_play_dead with an arbitrary hint
- ACPI/processor_idle: Add FFH state handling
- intel_idle: Provide the default enter_dead() handler
- Eliminate mwait_play_dead_cpuid_hint()
Bootup:
Build system:
- Raise the minimum GCC version to 8.1 (Brian Gerst)
- Raise the minimum LLVM version to 15.0.0
(Nathan Chancellor)
Kconfig: (Arnd Bergmann)
- Add cmpxchg8b support back to Geode CPUs
- Drop 32-bit "bigsmp" machine support
- Rework CONFIG_GENERIC_CPU compiler flags
- Drop configuration options for early 64-bit CPUs
- Remove CONFIG_HIGHMEM64G support
- Drop CONFIG_SWIOTLB for PAE
- Drop support for CONFIG_HIGHPTE
- Document CONFIG_X86_INTEL_MID as 64-bit-only
- Remove old STA2x11 support
- Only allow CONFIG_EISA for 32-bit
Headers:
- Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI and non-UAPI headers
(Thomas Huth)
Assembly code & machine code patching:
- x86/alternatives: Simplify alternative_call() interface (Josh Poimboeuf)
- x86/alternatives: Simplify callthunk patching (Peter Zijlstra)
- KVM: VMX: Use named operands in inline asm (Josh Poimboeuf)
- x86/hyperv: Use named operands in inline asm (Josh Poimboeuf)
- x86/traps: Cleanup and robustify decode_bug() (Peter Zijlstra)
- x86/kexec: Merge x86_32 and x86_64 code using macros from <asm/asm.h>
(Uros Bizjak)
- Use named operands in inline asm (Uros Bizjak)
- Improve performance by using asm_inline() for atomic locking instructions
(Uros Bizjak)
Earlyprintk:
- Harden early_serial (Peter Zijlstra)
NMI handler:
- Add an emergency handler in nmi_desc & use it in nmi_shootdown_cpus()
(Waiman Long)
Miscellaneous fixes and cleanups:
- by Ahmed S. Darwish, Andy Shevchenko, Ard Biesheuvel,
Artem Bityutskiy, Borislav Petkov, Brendan Jackman, Brian Gerst,
Dan Carpenter, Dr. David Alan Gilbert, H. Peter Anvin,
Ingo Molnar, Josh Poimboeuf, Kevin Brodsky, Mike Rapoport,
Lukas Bulwahn, Maciej Wieczor-Retman, Max Grobecker,
Patryk Wlazlyn, Pawan Gupta, Peter Zijlstra,
Philip Redkin, Qasim Ijaz, Rik van Riel, Thomas Gleixner,
Thorsten Blum, Tom Lendacky, Tony Luck, Uros Bizjak,
Vitaly Kuznetsov, Xin Li, liuye.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=Dcb3
-----END PGP SIGNATURE-----
Merge tag 'x86-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core x86 updates from Ingo Molnar:
"x86 CPU features support:
- Generate the <asm/cpufeaturemasks.h> header based on build config
(H. Peter Anvin, Xin Li)
- x86 CPUID parsing updates and fixes (Ahmed S. Darwish)
- Introduce the 'setcpuid=' boot parameter (Brendan Jackman)
- Enable modifying CPU bug flags with '{clear,set}puid=' (Brendan
Jackman)
- Utilize CPU-type for CPU matching (Pawan Gupta)
- Warn about unmet CPU feature dependencies (Sohil Mehta)
- Prepare for new Intel Family numbers (Sohil Mehta)
Percpu code:
- Standardize & reorganize the x86 percpu layout and related cleanups
(Brian Gerst)
- Convert the stackprotector canary to a regular percpu variable
(Brian Gerst)
- Add a percpu subsection for cache hot data (Brian Gerst)
- Unify __pcpu_op{1,2}_N() macros to __pcpu_op_N() (Uros Bizjak)
- Construct __percpu_seg_override from __percpu_seg (Uros Bizjak)
MM:
- Add support for broadcast TLB invalidation using AMD's INVLPGB
instruction (Rik van Riel)
- Rework ROX cache to avoid writable copy (Mike Rapoport)
- PAT: restore large ROX pages after fragmentation (Kirill A.
Shutemov, Mike Rapoport)
- Make memremap(MEMREMAP_WB) map memory as encrypted by default
(Kirill A. Shutemov)
- Robustify page table initialization (Kirill A. Shutemov)
- Fix flush_tlb_range() when used for zapping normal PMDs (Jann Horn)
- Clear _PAGE_DIRTY for kernel mappings when we clear _PAGE_RW
(Matthew Wilcox)
KASLR:
- x86/kaslr: Reduce KASLR entropy on most x86 systems, to support PCI
BAR space beyond the 10TiB region (CONFIG_PCI_P2PDMA=y) (Balbir
Singh)
CPU bugs:
- Implement FineIBT-BHI mitigation (Peter Zijlstra)
- speculation: Simplify and make CALL_NOSPEC consistent (Pawan Gupta)
- speculation: Add a conditional CS prefix to CALL_NOSPEC (Pawan
Gupta)
- RFDS: Exclude P-only parts from the RFDS affected list (Pawan
Gupta)
System calls:
- Break up entry/common.c (Brian Gerst)
- Move sysctls into arch/x86 (Joel Granados)
Intel LAM support updates: (Maciej Wieczor-Retman)
- selftests/lam: Move cpu_has_la57() to use cpuinfo flag
- selftests/lam: Skip test if LAM is disabled
- selftests/lam: Test get_user() LAM pointer handling
AMD SMN access updates:
- Add SMN offsets to exclusive region access (Mario Limonciello)
- Add support for debugfs access to SMN registers (Mario Limonciello)
- Have HSMP use SMN through AMD_NODE (Yazen Ghannam)
Power management updates: (Patryk Wlazlyn)
- Allow calling mwait_play_dead with an arbitrary hint
- ACPI/processor_idle: Add FFH state handling
- intel_idle: Provide the default enter_dead() handler
- Eliminate mwait_play_dead_cpuid_hint()
Build system:
- Raise the minimum GCC version to 8.1 (Brian Gerst)
- Raise the minimum LLVM version to 15.0.0 (Nathan Chancellor)
Kconfig: (Arnd Bergmann)
- Add cmpxchg8b support back to Geode CPUs
- Drop 32-bit "bigsmp" machine support
- Rework CONFIG_GENERIC_CPU compiler flags
- Drop configuration options for early 64-bit CPUs
- Remove CONFIG_HIGHMEM64G support
- Drop CONFIG_SWIOTLB for PAE
- Drop support for CONFIG_HIGHPTE
- Document CONFIG_X86_INTEL_MID as 64-bit-only
- Remove old STA2x11 support
- Only allow CONFIG_EISA for 32-bit
Headers:
- Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI and non-UAPI
headers (Thomas Huth)
Assembly code & machine code patching:
- x86/alternatives: Simplify alternative_call() interface (Josh
Poimboeuf)
- x86/alternatives: Simplify callthunk patching (Peter Zijlstra)
- KVM: VMX: Use named operands in inline asm (Josh Poimboeuf)
- x86/hyperv: Use named operands in inline asm (Josh Poimboeuf)
- x86/traps: Cleanup and robustify decode_bug() (Peter Zijlstra)
- x86/kexec: Merge x86_32 and x86_64 code using macros from
<asm/asm.h> (Uros Bizjak)
- Use named operands in inline asm (Uros Bizjak)
- Improve performance by using asm_inline() for atomic locking
instructions (Uros Bizjak)
Earlyprintk:
- Harden early_serial (Peter Zijlstra)
NMI handler:
- Add an emergency handler in nmi_desc & use it in
nmi_shootdown_cpus() (Waiman Long)
Miscellaneous fixes and cleanups:
- by Ahmed S. Darwish, Andy Shevchenko, Ard Biesheuvel, Artem
Bityutskiy, Borislav Petkov, Brendan Jackman, Brian Gerst, Dan
Carpenter, Dr. David Alan Gilbert, H. Peter Anvin, Ingo Molnar,
Josh Poimboeuf, Kevin Brodsky, Mike Rapoport, Lukas Bulwahn, Maciej
Wieczor-Retman, Max Grobecker, Patryk Wlazlyn, Pawan Gupta, Peter
Zijlstra, Philip Redkin, Qasim Ijaz, Rik van Riel, Thomas Gleixner,
Thorsten Blum, Tom Lendacky, Tony Luck, Uros Bizjak, Vitaly
Kuznetsov, Xin Li, liuye"
* tag 'x86-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (211 commits)
zstd: Increase DYNAMIC_BMI2 GCC version cutoff from 4.8 to 11.0 to work around compiler segfault
x86/asm: Make asm export of __ref_stack_chk_guard unconditional
x86/mm: Only do broadcast flush from reclaim if pages were unmapped
perf/x86/intel, x86/cpu: Replace Pentium 4 model checks with VFM ones
perf/x86/intel, x86/cpu: Simplify Intel PMU initialization
x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-UAPI headers
x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI headers
x86/locking/atomic: Improve performance by using asm_inline() for atomic locking instructions
x86/asm: Use asm_inline() instead of asm() in clwb()
x86/asm: Use CLFLUSHOPT and CLWB mnemonics in <asm/special_insns.h>
x86/hweight: Use asm_inline() instead of asm()
x86/hweight: Use ASM_CALL_CONSTRAINT in inline asm()
x86/hweight: Use named operands in inline asm()
x86/stackprotector/64: Only export __ref_stack_chk_guard on CONFIG_SMP
x86/head/64: Avoid Clang < 17 stack protector in startup code
x86/kexec: Merge x86_32 and x86_64 code using macros from <asm/asm.h>
x86/runtime-const: Add the RUNTIME_CONST_PTR assembly macro
x86/cpu/intel: Limit the non-architectural constant_tsc model checks
x86/mm/pat: Replace Intel x86_model checks with VFM ones
x86/cpu/intel: Fix fast string initialization for extended Families
...
[ Merge note, these two commits are identical:
- f3fa0e40df ("sched/clock: Don't define sched_clock_irqtime as static key")
- b9f2b29b94 ("sched: Don't define sched_clock_irqtime as static key")
The first one is a cherry-picked version of the second, and the first one
is already upstream. ]
Core & fair scheduler changes:
- Cancel the slice protection of the idle entity (Zihan Zhou)
- Reduce the default slice to avoid tasks getting an extra tick
(Zihan Zhou)
- Force propagating min_slice of cfs_rq when {en,de}queue tasks
(Tianchen Ding)
- Refactor can_migrate_task() to elimate looping (I Hsin Cheng)
- Add unlikey branch hints to several system calls (Colin Ian King)
- Optimize current_clr_polling() on certain architectures (Yujun Dong)
Deadline scheduler: (Juri Lelli)
- Remove redundant dl_clear_root_domain call
- Move dl_rebuild_rd_accounting to cpuset.h
Uclamp:
- Use the uclamp_is_used() helper instead of open-coding it (Xuewen Yan)
- Optimize sched_uclamp_used static key enabling (Xuewen Yan)
Scheduler topology support: (Juri Lelli)
- Ignore special tasks when rebuilding domains
- Add wrappers for sched_domains_mutex
- Generalize unique visiting of root domains
- Rebuild root domain accounting after every update
- Remove partition_and_rebuild_sched_domains
- Stop exposing partition_sched_domains_locked
RSEQ: (Michael Jeanson)
- Update kernel fields in lockstep with CONFIG_DEBUG_RSEQ=y
- Fix segfault on registration when rseq_cs is non-zero
- selftests: Add rseq syscall errors test
- selftests: Ensure the rseq ABI TLS is actually 1024 bytes
Membarriers:
- Fix redundant load of membarrier_state (Nysal Jan K.A.)
Scheduler debugging:
- Introduce and use preempt_model_str() (Sebastian Andrzej Siewior)
- Make CONFIG_SCHED_DEBUG unconditional (Ingo Molnar)
Fixes and cleanups:
- Always save/restore x86 TSC sched_clock() on suspend/resume
(Guilherme G. Piccoli)
- Misc fixes and cleanups (Thorsten Blum, Juri Lelli,
Sebastian Andrzej Siewior)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=SuQE
-----END PGP SIGNATURE-----
Merge tag 'sched-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
"Core & fair scheduler changes:
- Cancel the slice protection of the idle entity (Zihan Zhou)
- Reduce the default slice to avoid tasks getting an extra tick
(Zihan Zhou)
- Force propagating min_slice of cfs_rq when {en,de}queue tasks
(Tianchen Ding)
- Refactor can_migrate_task() to elimate looping (I Hsin Cheng)
- Add unlikey branch hints to several system calls (Colin Ian King)
- Optimize current_clr_polling() on certain architectures (Yujun
Dong)
Deadline scheduler: (Juri Lelli)
- Remove redundant dl_clear_root_domain call
- Move dl_rebuild_rd_accounting to cpuset.h
Uclamp:
- Use the uclamp_is_used() helper instead of open-coding it (Xuewen
Yan)
- Optimize sched_uclamp_used static key enabling (Xuewen Yan)
Scheduler topology support: (Juri Lelli)
- Ignore special tasks when rebuilding domains
- Add wrappers for sched_domains_mutex
- Generalize unique visiting of root domains
- Rebuild root domain accounting after every update
- Remove partition_and_rebuild_sched_domains
- Stop exposing partition_sched_domains_locked
RSEQ: (Michael Jeanson)
- Update kernel fields in lockstep with CONFIG_DEBUG_RSEQ=y
- Fix segfault on registration when rseq_cs is non-zero
- selftests: Add rseq syscall errors test
- selftests: Ensure the rseq ABI TLS is actually 1024 bytes
Membarriers:
- Fix redundant load of membarrier_state (Nysal Jan K.A.)
Scheduler debugging:
- Introduce and use preempt_model_str() (Sebastian Andrzej Siewior)
- Make CONFIG_SCHED_DEBUG unconditional (Ingo Molnar)
Fixes and cleanups:
- Always save/restore x86 TSC sched_clock() on suspend/resume
(Guilherme G. Piccoli)
- Misc fixes and cleanups (Thorsten Blum, Juri Lelli, Sebastian
Andrzej Siewior)"
* tag 'sched-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
cpuidle, sched: Use smp_mb__after_atomic() in current_clr_polling()
sched/debug: Remove CONFIG_SCHED_DEBUG
sched/debug: Remove CONFIG_SCHED_DEBUG from self-test config files
sched/debug, Documentation: Remove (most) CONFIG_SCHED_DEBUG references from documentation
sched/debug: Make CONFIG_SCHED_DEBUG functionality unconditional
sched/debug: Make 'const_debug' tunables unconditional __read_mostly
sched/debug: Change SCHED_WARN_ON() to WARN_ON_ONCE()
rseq/selftests: Fix namespace collision with rseq UAPI header
include/{topology,cpuset}: Move dl_rebuild_rd_accounting to cpuset.h
sched/topology: Stop exposing partition_sched_domains_locked
cgroup/cpuset: Remove partition_and_rebuild_sched_domains
sched/topology: Remove redundant dl_clear_root_domain call
sched/deadline: Rebuild root domain accounting after every update
sched/deadline: Generalize unique visiting of root domains
sched/topology: Wrappers for sched_domains_mutex
sched/deadline: Ignore special tasks when rebuilding domains
tracing: Use preempt_model_str()
xtensa: Rely on generic printing of preemption model
x86: Rely on generic printing of preemption model
s390: Rely on generic printing of preemption model
...
This pull request contains the following branches:
docs.2025.02.04a:
- Add broken-timing possibility to stallwarn.rst.
- Improve discussion of this_cpu_ptr(), add raw_cpu_ptr().
- Document self-propagating callbacks.
- Point call_srcu() to call_rcu() for detailed memory ordering.
- Add CONFIG_RCU_LAZY delays to call_rcu() kernel-doc header.
- Clarify RCU_LAZY and RCU_LAZY_DEFAULT_OFF help text.
- Remove references to old grace-period-wait primitives.
srcu.2025.02.05a:
- Introduce srcu_read_{un,}lock_fast(), which is similar to
srcu_read_{un,}lock_lite(): avoid smp_mb()s in lock and unlock at the
cost of calling synchronize_rcu() in synchronize_srcu(). Moreover, by
returning the percpu offset of the counter at srcu_read_lock_fast()
time, srcu_read_unlock_fast() can save extra pointer dereferencing,
which makes it faster than srcu_read_{un,}lock_lite().
srcu_read_{un,}lock_fast() are intended to replace
rcu_read_{un,}lock_trace() if possible.
torture.2025.02.05a:
- Add get_torture_init_jiffies() to return the start time of the test.
- Add a test_boost_holdoff module parameter to allow delaying boosting
tests when building rcutorture as built-in.
- Add grace period sequence number logging at the beginning and end of
failure/close-call results.
- Switch to hexadecimal for the expedited grace period sequence number
in the rcu_exp_grace_period trace point.
- Make cur_ops->format_gp_seqs take buffer length.
- Move RCU_TORTURE_TEST_{CHK_RDR_STATE,LOG_CPU} to bool.
- Complain when invalid SRCU reader_flavor is specified.
- Add FORCE_NEED_SRCU_NMI_SAFE Kconfig for testing, which forces SRCU
uses atomics even when percpu ops are NMI safe, and use the Kconfig
for SRCU lockdep testing.
misc.2025.03.04a:
- Split rcu_report_exp_cpu_mult() mask parameter and use for tracing.
- Remove READ_ONCE() for rdp->gpwrap access in __note_gp_changes().
- Fix get_state_synchronize_rcu_full() GP-start detection.
- Move RCU Tasks self-tests to core_initcall().
- Print segment lengths in show_rcu_nocb_gp_state().
- Make RCU watch ct_kernel_exit_state() warning.
- Flush console log from kernel_power_off().
- rcutorture: Allow a negative value for nfakewriters.
- rcu: Update TREE05.boot to test normal synchronize_rcu().
- rcu: Use _full() API to debug synchronize_rcu().
lazypreempt.2025.03.04a: Make RCU handle PREEMPT_LAZY better:
- Fix header guard for rcu_all_qs().
- rcu: Rename PREEMPT_AUTO to PREEMPT_LAZY.
- Update __cond_resched comment about RCU quiescent states.
- Handle unstable rdp in rcu_read_unlock_strict().
- Handle quiescent states for PREEMPT_RCU=n, PREEMPT_COUNT=y.
- osnoise: Provide quiescent states.
- Adjust rcutorture with possible PREEMPT_RCU=n && PREEMPT_COUNT=y
combination.
- Limit PREEMPT_RCU configurations.
- Make rcutorture senario TREE07 and senario TREE10 use PREEMPT_LAZY=y.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEj5IosQTPz8XU1wRHSXnow7UH+rgFAmfeBLQACgkQSXnow7UH
+rh11Qf/Rt6IZJ/YT/V9Sd+8hMx4O0BMh779pr9cD6mbAG+FDk2Yeva1m8vIdFOb
qId6oc8K/ef2JfFjSn0oHMzQP2D3XUyiJWPNbBDHv/D8Os8GZgjzu8dkxVkSbdbY
OxtvIflbcqFN1JDJfGKZnTEW0/YxGqfnS9b6R7iyyA7SOGQ/WubGOE5qNCqPufc9
zJiP+qTUFYQzCIiPlEJul39o9KboPogbt3QAAQjWmi3utd77ehJnm/15FvAjyau4
uhC2cnGfMY535rQaiaQeBQ/IHIowKripCq0JQFvcUNdyArZM3HOI2x79+2II6ft7
mjHskNODOIJHfW2o1RzQ0yRYAywFIg==
=J+mH
-----END PGP SIGNATURE-----
Merge tag 'rcu-next-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux
Pull RCU updates from Boqun Feng:
"Documentation:
- Add broken-timing possibility to stallwarn.rst
- Improve discussion of this_cpu_ptr(), add raw_cpu_ptr()
- Document self-propagating callbacks
- Point call_srcu() to call_rcu() for detailed memory ordering
- Add CONFIG_RCU_LAZY delays to call_rcu() kernel-doc header
- Clarify RCU_LAZY and RCU_LAZY_DEFAULT_OFF help text
- Remove references to old grace-period-wait primitives
srcu:
- Introduce srcu_read_{un,}lock_fast(), which is similar to
srcu_read_{un,}lock_lite(): avoid smp_mb()s in lock and unlock
at the cost of calling synchronize_rcu() in synchronize_srcu()
Moreover, by returning the percpu offset of the counter at
srcu_read_lock_fast() time, srcu_read_unlock_fast() can avoid
extra pointer dereferencing, which makes it faster than
srcu_read_{un,}lock_lite()
srcu_read_{un,}lock_fast() are intended to replace
rcu_read_{un,}lock_trace() if possible
RCU torture:
- Add get_torture_init_jiffies() to return the start time of the test
- Add a test_boost_holdoff module parameter to allow delaying
boosting tests when building rcutorture as built-in
- Add grace period sequence number logging at the beginning and end
of failure/close-call results
- Switch to hexadecimal for the expedited grace period sequence
number in the rcu_exp_grace_period trace point
- Make cur_ops->format_gp_seqs take buffer length
- Move RCU_TORTURE_TEST_{CHK_RDR_STATE,LOG_CPU} to bool
- Complain when invalid SRCU reader_flavor is specified
- Add FORCE_NEED_SRCU_NMI_SAFE Kconfig for testing, which forces SRCU
uses atomics even when percpu ops are NMI safe, and use the Kconfig
for SRCU lockdep testing
Misc:
- Split rcu_report_exp_cpu_mult() mask parameter and use for tracing
- Remove READ_ONCE() for rdp->gpwrap access in __note_gp_changes()
- Fix get_state_synchronize_rcu_full() GP-start detection
- Move RCU Tasks self-tests to core_initcall()
- Print segment lengths in show_rcu_nocb_gp_state()
- Make RCU watch ct_kernel_exit_state() warning
- Flush console log from kernel_power_off()
- rcutorture: Allow a negative value for nfakewriters
- rcu: Update TREE05.boot to test normal synchronize_rcu()
- rcu: Use _full() API to debug synchronize_rcu()
Make RCU handle PREEMPT_LAZY better:
- Fix header guard for rcu_all_qs()
- rcu: Rename PREEMPT_AUTO to PREEMPT_LAZY
- Update __cond_resched comment about RCU quiescent states
- Handle unstable rdp in rcu_read_unlock_strict()
- Handle quiescent states for PREEMPT_RCU=n, PREEMPT_COUNT=y
- osnoise: Provide quiescent states
- Adjust rcutorture with possible PREEMPT_RCU=n && PREEMPT_COUNT=y
combination
- Limit PREEMPT_RCU configurations
- Make rcutorture senario TREE07 and senario TREE10 use
PREEMPT_LAZY=y"
* tag 'rcu-next-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (59 commits)
rcutorture: Make scenario TREE07 build CONFIG_PREEMPT_LAZY=y
rcutorture: Make scenario TREE10 build CONFIG_PREEMPT_LAZY=y
rcu: limit PREEMPT_RCU configurations
rcutorture: Update ->extendables check for lazy preemption
rcutorture: Update rcutorture_one_extend_check() for lazy preemption
osnoise: provide quiescent states
rcu: Use _full() API to debug synchronize_rcu()
rcu: Update TREE05.boot to test normal synchronize_rcu()
rcutorture: Allow a negative value for nfakewriters
Flush console log from kernel_power_off()
context_tracking: Make RCU watch ct_kernel_exit_state() warning
rcu/nocb: Print segment lengths in show_rcu_nocb_gp_state()
rcu-tasks: Move RCU Tasks self-tests to core_initcall()
rcu: Fix get_state_synchronize_rcu_full() GP-start detection
torture: Make SRCU lockdep testing use srcu_read_lock_nmisafe()
srcu: Add FORCE_NEED_SRCU_NMI_SAFE Kconfig for testing
rcutorture: Complain when invalid SRCU reader_flavor is specified
rcutorture: Move RCU_TORTURE_TEST_{CHK_RDR_STATE,LOG_CPU} to bool
rcutorture: Make cur_ops->format_gp_seqs take buffer length
rcutorture: Add ftrace-compatible timestamp to GP# failure/close-call output
...
Add 3 per-cpu monitors as part of the sched model:
* scpd: schedule called with preemption disabled
Monitor to ensure schedule is called with preemption disabled
* snep: schedule does not enable preempt
Monitor to ensure schedule does not enable preempt
* sncid: schedule not called with interrupt disabled
Monitor to ensure schedule is not called with interrupt disabled
To: Ingo Molnar <mingo@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/20250305140406.350227-6-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a per-task monitor as part of the sched model:
* snroc: set non runnable on its own context
Monitor to ensure set_state happens only in the respective task's context
To: Ingo Molnar <mingo@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/20250305140406.350227-5-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add 2 per-cpu monitors as part of the sched model:
* sco: scheduling context operations
Monitor to ensure sched_set_state happens only in thread context
* tss: task switch while scheduling
Monitor to ensure sched_switch happens only in scheduling context
To: Ingo Molnar <mingo@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/20250305140406.350227-4-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Monitors describing complex systems, such as the scheduler, can easily
grow to the point where they are just hard to understand because of the
many possible state transitions.
Often it is possible to break such descriptions into smaller monitors,
sharing some or all events. Enabling those smaller monitors concurrently
is, in fact, testing the system as if we had one single larger monitor.
Splitting models into multiple specification is not only easier to
understand, but gives some more clues when we see errors.
Add the possibility to create container monitors, whose only purpose is
to host other nested monitors. Enabling a container monitor enables all
nested ones, but it's still possible to enable nested monitors
independently.
Add the sched monitor as first container, for now empty.
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/20250305140406.350227-3-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
An update was made to up the module ref count when a synthetic event is
registered for both trace and perf events. But if perf is not configured
in, the perf enums used will cause the kernel to fail to build.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Douglas Raillard <douglas.raillard@arm.com>
Link: https://lore.kernel.org/20250323152151.528b5ced@batman.local.home
Fixes: 21581dd4e7 ("tracing: Ensure module defining synth event cannot be unloaded while tracing")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202503232230.TeREVy8R-lkp@intel.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Convert the event_hash array in trace_output.c to use the generic
hashtable implementation from hashtable.h instead of the manually
implemented hash table.
This simplifies the code and makes it more maintainable by using the
standard hashtable API defined in hashtable.h.
Rename EVENT_HASHSIZE to EVENT_HASH_BITS to properly reflect its new
meaning as the number of bits for the hashtable size.
Link: https://lore.kernel.org/20250323132800.3010783-1-sashal@kernel.org
Link: https://lore.kernel.org/20250319190545.3058319-1-sashal@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently, using synth_event_delete() will fail if the event is being
used (tracing in progress), but that is normally done in the module exit
function. At that stage, failing is problematic as returning a non-zero
status means the module will become locked (impossible to unload or
reload again).
Instead, ensure the module exit function does not get called in the
first place by increasing the module refcnt when the event is enabled.
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 35ca5207c2 ("tracing: Add synthetic event command generation functions")
Link: https://lore.kernel.org/20250318180906.226841-1-douglas.raillard@arm.com
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When __ftrace_event_enable_disable invokes the class callback to
unregister the event, the return value is not reported up to the
caller, hence leading to event unregister failures being silently
ignored.
This patch assigns the ret variable to the invocation of the
event unregister callback, so that its return value is stored
and reported to the caller, and it raises a warning in case
of error.
Link: https://lore.kernel.org/20250321170821.101403-1-gpaoloni@redhat.com
Signed-off-by: Gabriele Paoloni <gpaoloni@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Lockdep reports this deadlock log:
osnoise: could not start sampling thread
============================================
WARNING: possible recursive locking detected
--------------------------------------------
CPU0
----
lock(cpu_hotplug_lock);
lock(cpu_hotplug_lock);
Call Trace:
<TASK>
print_deadlock_bug+0x282/0x3c0
__lock_acquire+0x1610/0x29a0
lock_acquire+0xcb/0x2d0
cpus_read_lock+0x49/0x120
stop_per_cpu_kthreads+0x7/0x60
start_kthread+0x103/0x120
osnoise_hotplug_workfn+0x5e/0x90
process_one_work+0x44f/0xb30
worker_thread+0x33e/0x5e0
kthread+0x206/0x3b0
ret_from_fork+0x31/0x50
ret_from_fork_asm+0x11/0x20
</TASK>
This is the deadlock scenario:
osnoise_hotplug_workfn()
guard(cpus_read_lock)(); // first lock call
start_kthread(cpu)
if (IS_ERR(kthread)) {
stop_per_cpu_kthreads(); {
cpus_read_lock(); // second lock call. Cause the AA deadlock
}
}
It is not necessary to call stop_per_cpu_kthreads() which stops osnoise
kthread for every other CPUs in the system if a failure occurs during
hotplug of a certain CPU.
For start_per_cpu_kthreads(), if the start_kthread() call fails,
this function calls stop_per_cpu_kthreads() to handle the error.
Therefore, similarly, there is no need to call stop_per_cpu_kthreads()
again within start_kthread().
So just remove stop_per_cpu_kthreads() from start_kthread to solve this issue.
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20250321095249.2739397-1-ranxiaokai627@163.com
Fixes: c8895e271f ("trace/osnoise: Support hotplug operations")
Signed-off-by: Ran Xiaokai <ran.xiaokai@zte.com.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The vast majority of ftrace event print fmt consist of a space-separated
field=value pair. Synthetic event currently use a comma-separated
field=value pair, which sticks out from events created via more
classical means.
Align the format of synth events so they look just like any other event,
for better consistency and less headache when doing crude text-based
data processing.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250319215028.1680278-1-douglas.raillard@arm.com
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Kairui reported a UAF issue in print_graph_function_flags() during
ftrace stress testing [1]. This issue can be reproduced if puting a
'mdelay(10)' after 'mutex_unlock(&trace_types_lock)' in s_start(),
and executing the following script:
$ echo function_graph > current_tracer
$ cat trace > /dev/null &
$ sleep 5 # Ensure the 'cat' reaches the 'mdelay(10)' point
$ echo timerlat > current_tracer
The root cause lies in the two calls to print_graph_function_flags
within print_trace_line during each s_show():
* One through 'iter->trace->print_line()';
* Another through 'event->funcs->trace()', which is hidden in
print_trace_fmt() before print_trace_line returns.
Tracer switching only updates the former, while the latter continues
to use the print_line function of the old tracer, which in the script
above is print_graph_function_flags.
Moreover, when switching from the 'function_graph' tracer to the
'timerlat' tracer, s_start only calls graph_trace_close of the
'function_graph' tracer to free 'iter->private', but does not set
it to NULL. This provides an opportunity for 'event->funcs->trace()'
to use an invalid 'iter->private'.
To fix this issue, set 'iter->private' to NULL immediately after
freeing it in graph_trace_close(), ensuring that an invalid pointer
is not passed to other tracers. Additionally, clean up the unnecessary
'iter->private = NULL' during each 'cat trace' when using wakeup and
irqsoff tracers.
[1] https://lore.kernel.org/all/20231112150030.84609-1-ryncsn@gmail.com/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Zheng Yejian <zhengyejian1@huawei.com>
Link: https://lore.kernel.org/20250320122137.23635-1-wutengda@huaweicloud.com
Fixes: eecb91b9f9 ("tracing: Fix memleak due to race between current_tracer and trace")
Closes: https://lore.kernel.org/all/CAMgjq7BW79KDSCyp+tZHjShSzHsScSiJxn5ffskp-QzVM06fxw@mail.gmail.com/
Reported-by: Kairui Song <kasong@tencent.com>
Signed-off-by: Tengda Wu <wutengda@huaweicloud.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
'event_trigger_ops mwifiex_if_ops' are not modified in these drivers.
Constifying these structures moves some data to a read-only section, so
increase overall security, especially when the structure holds some
function pointers.
On a x86_64, with allmodconfig, as an example:
Before:
======
text data bss dec hex filename
31368 9024 6200 46592 b600 kernel/trace/trace_events_trigger.o
After:
=====
text data bss dec hex filename
31752 8608 6200 46560 b5e0 kernel/trace/trace_events_trigger.o
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/66e8f990e649678e4be37d4d1a19158ca0dea2f4.1741521295.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The perf_event_read_event_output helper is currently only available to
tracing protrams, but is useful for other BPF programs like sched_ext
schedulers. When the helper is available, provide its bpf_func_proto
directly from the bpf base_proto.
Signed-off-by: Emil Tsalapatis (Meta) <emil@etsalapatis.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20250318030753.10949-1-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
- tprobe-events: Fix to clean up tprobe correctly when module unload
tprobe (Tracepoint probe) event does not set TRACEPOINT_STUB to its
'tpoint' pointer when unloading module, thus it is shown as a normal
'fprobe' instead of 'tprobe' and never comes back.
- tprobe-events: Fix leakage of module refcount
When a tprobe's target module is loaded, it gets the module's refcount
in the module notifier but forgot to put it after registering the probe
on it. Fix to get the refcount only when registering tprobe.
-----BEGIN PGP SIGNATURE-----
iQFPBAABCgA5FiEEh7BulGwFlgAOi5DV2/sHvwUrPxsFAmfYFpobHG1hc2FtaS5o
aXJhbWF0c3VAZ21haWwuY29tAAoJENv7B78FKz8bi0kH/3wSyMa7wP7pSPQ1Hq8i
ZLeKa7pSS3X39IE6urvpYrTUBRw75tqSSozyF6g8jM3Tj8ISpF9rlZJ6ct775mTR
9Ld9wPNgnj0pCZU29VGf9TPm3JCm5V0h0bhE9qZp8wZRiedbwg9e6uZ92LBLAmW+
MisEmLsKrYcOUF1bwhLwoNRzlwidhHKCBAF6vUqVC62kktCe08XKKmiusslVfEZz
KrU0XM1MPnncWd2Cp3qw9ywcC40ES61lBdhMjJcGM3yKqKqlJSQxIBa5rOl0TlJA
D58bEpPhoyGT3sWS7UlqVjdkHy9NtpFx3nvcvPGCrDMLl9qwj4aSrwUBjK693RS7
Dyo=
=D3X0
-----END PGP SIGNATURE-----
Merge tag 'probes-fixes-v6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes fixes from Masami Hiramatsu:
- Clean up tprobe correctly when module unload
Tracepoint probes do not set TRACEPOINT_STUB on the 'tpoint' pointer
when unloading a module, thus they show as a normal 'fprobe' instead
of 'tprobe' and never come back
- Fix leakage of tprobe module refcount
When a tprobe's target module is loaded, it gets the module's
refcount in the module notifier but forgot to put it after
registering the probe on it.
Fix it by getting the refcount only when registering tprobe.
* tag 'probes-fixes-v6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: tprobe-events: Fix leakage of module refcount
tracing: tprobe-events: Fix to clean up tprobe correctly when module unload
Use preempt_model_str() instead of manually conducting the preemption
model.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: "Steven Rostedt (Google)" <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20250314160810.2373416-10-bigeasy@linutronix.de
Tracing instances have a ref count to keep them around while files within
their directories are open. This prevents them from being deleted while
they are used. The histogram code had some files that needed to take the
ref count and that was added, but the error paths did not decrement the
ref counts. This caused the instances from ever being removed if a
histogram file failed to open due to some error.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ9cE8hQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qtm8AQDrdfwo63g/K0xpM0Uej9Ex5pBkHEq/
WwCI2hUbPya0wAEAtEcfvgt7P0GuO0PNOYY3uzhAokfBiN04elatbLEetQ4=
=i35g
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fix from Steven Rostedt:
"Fix ref count of trace_array in error path of histogram file open
Tracing instances have a ref count to keep them around while files
within their directories are open. This prevents them from being
deleted while they are used.
The histogram code had some files that needed to take the ref count
and that was added, but the error paths did not decrement the ref
counts. This caused the instances from ever being removed if a
histogram file failed to open due to some error"
* tag 'trace-v6.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Correct the refcount if the hist/hist_debug file fails to open
When enabling the tracepoint at loading module, the target module
refcount is incremented by find_tracepoint_in_module(). But it is
unnecessary because the module is not unloaded while processing
module loading callbacks.
Moreover, the refcount is not decremented in that function.
To be clear the module refcount handling, move the try_module_get()
callsite to trace_fprobe_create_internal(), where it is actually
required.
Link: https://lore.kernel.org/all/174182761071.83274.18334217580449925882.stgit@devnote2/
Fixes: 57a7e6de9e ("tracing/fprobe: Support raw tracepoints on future loaded modules")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
When unloading module, the tprobe events are not correctly cleaned
up. Thus it becomes `fprobe-event` and never be enabled again even
if loading the same module again.
For example;
# cd /sys/kernel/tracing
# modprobe trace_events_sample
# echo 't:my_tprobe foo_bar' >> dynamic_events
# cat dynamic_events
t:tracepoints/my_tprobe foo_bar
# rmmod trace_events_sample
# cat dynamic_events
f:tracepoints/my_tprobe foo_bar
As you can see, the second time my_tprobe starts with 'f' instead
of 't'.
This unregisters the fprobe and tracepoint callback when module is
unloaded but marks the fprobe-event is tprobe-event.
Link: https://lore.kernel.org/all/174158724946.189309.15826571379395619524.stgit@mhiramat.tok.corp.google.com/
Fixes: 57a7e6de9e ("tracing/fprobe: Support raw tracepoints on future loaded modules")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
The function event_{hist,hist_debug}_open() maintains the refcount of
'file->tr' and 'file' through tracing_open_file_tr(). However, it does
not roll back these counts on subsequent failure paths, resulting in a
refcount leak.
A very obvious case is that if the hist/hist_debug file belongs to a
specific instance, the refcount leak will prevent the deletion of that
instance, as it relies on the condition 'tr->ref == 1' within
__remove_instance().
Fix this by calling tracing_release_file_tr() on all failure paths in
event_{hist,hist_debug}_open() to correct the refcount.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Zheng Yejian <zhengyejian1@huawei.com>
Link: https://lore.kernel.org/20250314065335.1202817-1-wutengda@huaweicloud.com
Fixes: 1cc111b9cd ("tracing: Fix uaf issue when open the hist or hist_debug file")
Signed-off-by: Tengda Wu <wutengda@huaweicloud.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
__module_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.
Replace the preempt_disable() section around __module_address() with
RCU.
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matt Bobrowski <mattbobrowski@google.com>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: bpf@vger.kernel.org
Cc: linux-trace-kernel@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20250129084751.tH6iidUO@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
The modules list and module::kallsyms can be accessed under RCU
assumption.
Remove module_assert_mutex_or_preempt() from find_module_all() so it can
be used under RCU protection without warnings. Update its callers to use
RCU protection instead of preempt_disable().
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-trace-kernel@vger.kernel.org
Cc: live-patching@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250108090457.512198-7-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Variable func is not effectively used, so delete it.
kernel/trace/trace_functions_graph.c:925:16: warning: variable ‘func’ set but not used.
This happened because the variable "func" which came from "call->func" was
replaced by "ret_func" coming from "graph_ret->func" but "func" wasn't
removed after the replacement.
Link: https://lore.kernel.org/20250307021412.119107-1-jiapeng.chong@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=19250
Fixes: ff5c9c576e ("ftrace: Add support for function argument to graph tracer")
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2 seq_puts() calls can be merged.
It saves a few lines of code and a few cycles, should it matter.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/845caa94b74cea8d72c158bf1994fe250beee28c.1739979791.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
To reduce RCU noise for nohz_full configurations, osnoise depends
on cond_resched() providing quiescent states for PREEMPT_RCU=n
configurations. For PREEMPT_RCU=y configurations -- where
cond_resched() is a stub -- we do this by directly calling
rcu_momentary_eqs().
With (PREEMPT_LAZY=y, PREEMPT_DYNAMIC=n), however, we have a
configuration with (PREEMPTION=y, PREEMPT_RCU=n) where neither
of the above can help.
Handle that by providing an explicit quiescent state here for all
configurations.
As mentioned above this is not needed for non-stubbed cond_resched(),
but, providing a quiescent state here just pulls in one that a future
cond_resched() would provide, so doesn't cause any extra work for
this configuration.
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Some monitor files like the main header and the Kconfig are missing the
license identifier.
Add it to those and make sure the automatic generation script includes
the line in newly created monitors.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/20250218123121.253551-3-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Wire up the code to print function arguments in the function tracer.
This functionality can be enabled/disabled during runtime with
options/func-args.
ping-689 [004] b.... 77.170220: dummy_xmit(skb = 0x82904800, dev = 0x882d0000) <-dev_hard_start_xmit
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Guo Ren <guoren@kernel.org>
Cc: Donglin Peng <dolinux.peng@gmail.com>
Cc: Zheng Yejian <zhengyejian@huaweicloud.com>
Link: https://lore.kernel.org/20250227185823.154996172@goodmis.org
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Co-developed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently, when function_graph is started, it looks at the option
funcgraph-args, and if it is set, it will enable tracing of the arguments.
But if tracing is already running, and the user enables funcgraph-args, it
will have no effect. Instead, it should enable argument tracing when it is
enabled, even if it means disabling the function graph tracing for a short
time in order to do the transition.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Guo Ren <guoren@kernel.org>
Cc: Donglin Peng <dolinux.peng@gmail.com>
Cc: Zheng Yejian <zhengyejian@huaweicloud.com>
Link: https://lore.kernel.org/20250227185822.978998710@goodmis.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Wire up the code to print function arguments in the function graph
tracer. This functionality can be enabled/disabled during runtime with
options/funcgraph-args.
Example usage:
6) | dummy_xmit [dummy](skb = 0x8887c100, dev = 0x872ca000) {
6) | consume_skb(skb = 0x8887c100) {
6) | skb_release_head_state(skb = 0x8887c100) {
6) 0.178 us | sock_wfree(skb = 0x8887c100)
6) 0.627 us | }
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Guo Ren <guoren@kernel.org>
Cc: Donglin Peng <dolinux.peng@gmail.com>
Cc: Zheng Yejian <zhengyejian@huaweicloud.com>
Link: https://lore.kernel.org/20250227185822.810321199@goodmis.org
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Co-developed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a function to decode argument types with the help of BTF. Will
be used to display arguments in the function and function graph
tracer.
It can only handle simply arguments and up to FTRACE_REGS_MAX_ARGS number
of arguments. When it hits a max, it will print ", ...":
page_to_skb(vi=0xffff8d53842dc980, rq=0xffff8d53843a0800, page=0xfffffc2e04337c00, offset=6160, len=64, truesize=1536, ...)
And if it hits an argument that is not recognized, it will print the raw
value and the type of argument it is:
make_vfsuid(idmap=0xffffffff87f99db8, fs_userns=0xffffffff87e543c0, kuid=0x0 (STRUCT))
__pti_set_user_pgtbl(pgdp=0xffff8d5384ab47f8, pgd=0x110e74067 (STRUCT))
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Guo Ren <guoren@kernel.org>
Cc: Donglin Peng <dolinux.peng@gmail.com>
Cc: Zheng Yejian <zhengyejian@huaweicloud.com>
Link: https://lore.kernel.org/20250227185822.639418500@goodmis.org
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Co-developed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ftrace_free_filter() is used to reset the ops filters. But it must be
done if the ops is not currently active (tracing). If it is, it will mess
up the ftrace accounting of what functions are attached and what is not.
WARN and exit the ftrace_free_filter() if the ops is active when it is
called.
Currently, it doesn't seem if anything does this, but it may in the
future.
Link: https://lore.kernel.org/all/20250219095330.2e9f171c@gandalf.local.home/
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250219135040.3a9fbe00@gandalf.local.home
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- probe-events: Some issues are fixed.
. probe-events: Remove unused MAX_ARG_BUF_LEN macro.
MAX_ARG_BUF_LEN is not used so remove it.
. fprobe-events: Log error for exceeding the number of entry args.
Since the max number of entry args is limited, it should be checked
and rejected when the parser detects it.
. tprobe-events: Reject invalid tracepoint name
User can specify an invalid tracepoint name e.g. including '/', then
the new event is not defined correctly in the eventfs.
. tprobe-events: Fix a memory leak when tprobe defined with $retval
There is a memory leak if tprobe is defined with $retval.
-----BEGIN PGP SIGNATURE-----
iQFPBAABCgA5FiEEh7BulGwFlgAOi5DV2/sHvwUrPxsFAmfFKkcbHG1hc2FtaS5o
aXJhbWF0c3VAZ21haWwuY29tAAoJENv7B78FKz8b/F4H/10qmUSsec9+IbQseg0E
MSRxAhJQ+xOcLfGsWhblW2zirkw9o4PghZYwBodkastu4Wgq2M5ASKd6KqUY2o7D
CX+tCoXf80SDLEVd2go5m72Ml40rrGDEgLvS5YcEa4Iqr5nPZrvCJ7rl2tlqupQH
W2ttOTkX9H28phAFDCsdl5ZJUCJRxlFc6fYG0yZYHsFdRub9J2LPiMTMwIlu56YS
8HH3NxS+wxlKK2I4VfD8mFsOnrNh7MFDLOOwNMlKWvm2wSPbPmVho+eXLAc5xyTO
d+vUpkp4Dp9WWCLuNdO/sqY0IKngO2sM++WbtL/YPP8YijqsrImep4PCR8/fvlN6
Urs=
=dyZm
-----END PGP SIGNATURE-----
Merge tag 'probes-fixes-v6.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probe events fixes from Masami Hiramatsu:
- probe-events: Remove unused MAX_ARG_BUF_LEN macro - it is not used
- fprobe-events: Log error for exceeding the number of entry args.
Since the max number of entry args is limited, it should be checked
and rejected when the parser detects it.
- tprobe-events: Reject invalid tracepoint name
If a user specifies an invalid tracepoint name (e.g. including '/')
then the new event is not defined correctly in the eventfs.
- tprobe-events: Fix a memory leak when tprobe defined with $retval
There is a memory leak if tprobe is defined with $retval.
* tag 'probes-fixes-v6.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: probe-events: Remove unused MAX_ARG_BUF_LEN macro
tracing: fprobe-events: Log error for exceeding the number of entry args
tracing: tprobe-events: Reject invalid tracepoint name
tracing: tprobe-events: Fix a memory leak when tprobe with $retval
Check whether denominator expression x * (x - 1) * 1000 mod {2^32, 2^64}
produce zero and skip stddev computation in that case.
For now don't care about rec->counter * rec->counter overflow because
rec->time * rec->time overflow will likely happen earlier.
Cc: stable@vger.kernel.org
Cc: Wen Yang <wenyang@linux.alibaba.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250206090156.1561783-1-kniv@yandex-team.ru
Fixes: e31f7939c1 ("ftrace: Avoid potential division by zero in function profiler")
Signed-off-by: Nikolay Kuratov <kniv@yandex-team.ru>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The following commands causes a crash:
~# cd /sys/kernel/tracing/events/rcu/rcu_callback
~# echo 'hist:name=bad:keys=common_pid:onmax(bogus).save(common_pid)' > trigger
bash: echo: write error: Invalid argument
~# echo 'hist:name=bad:keys=common_pid' > trigger
Because the following occurs:
event_trigger_write() {
trigger_process_regex() {
event_hist_trigger_parse() {
data = event_trigger_alloc(..);
event_trigger_register(.., data) {
cmd_ops->reg(.., data, ..) [hist_register_trigger()] {
data->ops->init() [event_hist_trigger_init()] {
save_named_trigger(name, data) {
list_add(&data->named_list, &named_triggers);
}
}
}
}
ret = create_actions(); (return -EINVAL)
if (ret)
goto out_unreg;
[..]
ret = hist_trigger_enable(data, ...) {
list_add_tail_rcu(&data->list, &file->triggers); <<<---- SKIPPED!!! (this is important!)
[..]
out_unreg:
event_hist_unregister(.., data) {
cmd_ops->unreg(.., data, ..) [hist_unregister_trigger()] {
list_for_each_entry(iter, &file->triggers, list) {
if (!hist_trigger_match(data, iter, named_data, false)) <- never matches
continue;
[..]
test = iter;
}
if (test && test->ops->free) <<<-- test is NULL
test->ops->free(test) [event_hist_trigger_free()] {
[..]
if (data->name)
del_named_trigger(data) {
list_del(&data->named_list); <<<<-- NEVER gets removed!
}
}
}
}
[..]
kfree(data); <<<-- frees item but it is still on list
The next time a hist with name is registered, it causes an u-a-f bug and
the kernel can crash.
Move the code around such that if event_trigger_register() succeeds, the
next thing called is hist_trigger_enable() which adds it to the list.
A bunch of actions is called if get_named_trigger_data() returns false.
But that doesn't need to be called after event_trigger_register(), so it
can be moved up, allowing event_trigger_register() to be called just
before hist_trigger_enable() keeping them together and allowing the
file->triggers to be properly populated.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250227163944.1c37f85f@gandalf.local.home
Fixes: 067fe038e7 ("tracing: Add variable reference handling to hist triggers")
Reported-by: Tomas Glozar <tglozar@redhat.com>
Tested-by: Tomas Glozar <tglozar@redhat.com>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Closes: https://lore.kernel.org/all/CAP4=nvTsxjckSBTz=Oe_UYh8keD9_sZC4i++4h72mJLic4_W4A@mail.gmail.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add trace events that fire at osnoise and timerlat sample generation, in
addition to the already existing noise and threshold events.
This allows processing the samples directly in the kernel, either with
ftrace triggers or with BPF.
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250203090418.1458923-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Tested-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add error message when the number of entry argument exceeds the
maximum size of entry data.
This is currently checked when registering fprobe, but in this case
no error message is shown in the error_log file.
Link: https://lore.kernel.org/all/174055074269.4079315.17809232650360988538.stgit@mhiramat.tok.corp.google.com/
Fixes: 25f00e40ce ("tracing/probes: Support $argN in return probe (kprobe and fprobe)")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Commit 57a7e6de9e ("tracing/fprobe: Support raw tracepoints on
future loaded modules") allows user to set a tprobe on non-exist
tracepoint but it does not check the tracepoint name is acceptable.
So it leads tprobe has a wrong character for events (e.g. with
subsystem prefix). In this case, the event is not shown in the
events directory.
Reject such invalid tracepoint name.
The tracepoint name must consist of alphabet or digit or '_'.
Link: https://lore.kernel.org/all/174055073461.4079315.15875502830565214255.stgit@mhiramat.tok.corp.google.com/
Fixes: 57a7e6de9e ("tracing/fprobe: Support raw tracepoints on future loaded modules")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: stable@vger.kernel.org
Fix a memory leak when a tprobe is defined with $retval. This
combination is not allowed, but the parse_symbol_and_return() does
not free the *symbol which should not be used if it returns the error.
Thus, it leaks the *symbol memory in that error path.
Link: https://lore.kernel.org/all/174055072650.4079315.3063014346697447838.stgit@mhiramat.tok.corp.google.com/
Fixes: ce51e6153f ("tracing: fprobe-event: Fix to check tracepoint event and return")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: stable@vger.kernel.org
It seems that the attr parameter was never been used in security
checks since it was first introduced by:
commit da97e18458 ("perf_event: Add support for LSM and SELinux checks")
so remove it.
Signed-off-by: Luo Gengkun <luogengkun@huaweicloud.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Fix the following deadlock:
CPU A
_free_event()
perf_kprobe_destroy()
mutex_lock(&event_mutex)
perf_trace_event_unreg()
synchronize_rcu_tasks_trace()
There are several paths where _free_event() grabs event_mutex
and calls sync_rcu_tasks_trace. Above is one such case.
CPU B
bpf_prog_test_run_syscall()
rcu_read_lock_trace()
bpf_prog_run_pin_on_cpu()
bpf_prog_load()
bpf_tracing_func_proto()
trace_set_clr_event()
mutex_lock(&event_mutex)
Delegate trace_set_clr_event() to workqueue to avoid
such lock dependency.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250224221637.4780-1-alexei.starovoitov@gmail.com
Sometimes tracing is used to debug issues during the boot process. Since
the trace buffer has a limited amount of storage, it may be prudent to
disable tracing after the boot is finished, otherwise the critical
information may be overwritten. With this option, the main tracing buffer
will be turned off at the end of the boot process.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lore.kernel.org/20250208103017.48a7ec83@batman.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
As kaslr_offset() is architecture dependent and also may not be defined by
all architectures, when zeroing out unused weak functions, do not check
against kaslr_offset(), but instead check if the address is within the
kernel text sections. If KASLR added a shift to the zeroed out function,
it would still not be located in the kernel text. This is a more robust
way to test if the text is valid or not.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: "Arnd Bergmann" <arnd@arndb.de>
Link: https://lore.kernel.org/20250225182054.471759017@goodmis.org
Fixes: ef378c3b82 ("scripts/sorttable: Zero out weak functions in mcount_loc table")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Reported-by: Mark Brown <broonie@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/all/20250224180805.GA1536711@ax162/
Closes: https://lore.kernel.org/all/5225b07b-a9b2-4558-9d5f-aa60b19f6317@sirena.org.uk/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The addresses in the mcount_loc can be zeroed and then moved by KASLR
making them invalid addresses. ftrace_call_addr() for ARM 64 expects a
valid address to kernel text. If the addr read from the mcount_loc section
is invalid, it must not call ftrace_call_addr(). Move the addr check
before calling ftrace_call_addr() in ftrace_process_locs().
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/20250225182054.290128736@goodmis.org
Fixes: ef378c3b82 ("scripts/sorttable: Zero out weak functions in mcount_loc table")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Reported-by: "Arnd Bergmann" <arnd@arndb.de>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/all/20250225025631.GA271248@ax162/
Closes: https://lore.kernel.org/all/91523154-072b-437b-bbdc-0b70e9783fd0@app.fastmail.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
kmemleak reports the following memory leak after reading set_event file:
# cat /sys/kernel/tracing/set_event
# cat /sys/kernel/debug/kmemleak
unreferenced object 0xff110001234449e0 (size 16):
comm "cat", pid 13645, jiffies 4294981880
hex dump (first 16 bytes):
01 00 00 00 00 00 00 00 a8 71 e7 84 ff ff ff ff .........q......
backtrace (crc c43abbc):
__kmalloc_cache_noprof+0x3ca/0x4b0
s_start+0x72/0x2d0
seq_read_iter+0x265/0x1080
seq_read+0x2c9/0x420
vfs_read+0x166/0xc30
ksys_read+0xf4/0x1d0
do_syscall_64+0x79/0x150
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The issue can be reproduced regardless of whether set_event is empty or
not. Here is an example about the valid content of set_event.
# cat /sys/kernel/tracing/set_event
sched:sched_process_fork
sched:sched_switch
sched:sched_wakeup
*:*:mod:trace_events_sample
The root cause is that s_next() returns NULL when nothing is found.
This results in s_stop() attempting to free a NULL pointer because its
parameter is NULL.
Fix the issue by freeing the memory appropriately when s_next() fails
to find anything.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250220031528.7373-1-ahuang12@lenovo.com
Fixes: b355247df1 ("tracing: Cache ":mod:" events for modules not loaded yet")
Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function tracer should record the preemption level at the point when
the function is invoked. If the tracing subsystem decrement the
preemption counter it needs to correct this before feeding the data into
the trace buffer. This was broken in the commit cited below while
shifting the preempt-disabled section.
Use tracing_gen_ctx_dec() which properly subtracts one from the
preemption counter on a preemptible kernel.
Cc: stable@vger.kernel.org
Cc: Wander Lairson Costa <wander@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/20250220140749.pfw8qoNZ@linutronix.de
Fixes: ce5e48036c ("ftrace: disable preemption when recursion locked")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Wander Lairson Costa <wander@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When adding a new fprobe, it will update the function hash to the
functions the fprobe is attached to and register with function graph to
have it call the registered functions. The fprobe_graph_active variable
keeps track of the number of fprobes that are using function graph.
If two fprobes attach to the same function, it increments the
fprobe_graph_active for each of them. But when they are removed, the first
fprobe to be removed will see that the function it is attached to is also
used by another fprobe and it will not remove that function from
function_graph. The logic will skip decrementing the fprobe_graph_active
variable.
This causes the fprobe_graph_active variable to not go to zero when all
fprobes are removed, and in doing so it does not unregister from
function graph. As the fgraph ops hash will now be empty, and an empty
filter hash means all functions are enabled, this triggers function graph
to add a callback to the fprobe infrastructure for every function!
# echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events
# echo "f:myevent2 kernel_clone%return" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc0024000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# > /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
trace_initcall_start_cb (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
try_to_run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
x86_pmu_show_pmu_cap (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
cleanup_rapl_pmus (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
uncore_free_pcibus_map (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
uncore_types_exit (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
uncore_pci_exit.part.0 (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
kvm_shutdown (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
vmx_dump_msrs (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
[..]
# cat /sys/kernel/tracing/enabled_functions | wc -l
54702
If a fprobe is being removed and all its functions are also traced by
other fprobes, still decrement the fprobe_graph_active counter.
Cc: stable@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250220202055.565129766@goodmis.org
Fixes: 4346ba1604 ("fprobe: Rewrite fprobe on function-graph tracer")
Closes: https://lore.kernel.org/all/20250217114918.10397-A-hca@linux.ibm.com/
Reported-by: Heiko Carstens <hca@linux.ibm.com>
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the last fprobe is removed, it calls unregister_ftrace_graph() to
remove the graph_ops from function graph. The issue is when it does so, it
calls return before removing the function from its graph ops via
ftrace_set_filter_ips(). This leaves the last function lingering in the
fprobe's fgraph ops and if a probe is added it also enables that last
function (even though the callback will just drop it, it does add unneeded
overhead to make that call).
# echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# echo "f:myevent2 schedule_timeout" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
schedule_timeout (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# > /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
# echo "f:myevent3 kmem_cache_free" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kmem_cache_free (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
schedule_timeout (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
The above enabled a fprobe on kernel_clone, and then on schedule_timeout.
The content of the enabled_functions shows the functions that have a
callback attached to them. The fprobe attached to those functions
properly. Then the fprobes were cleared, and enabled_functions was empty
after that. But after adding a fprobe on kmem_cache_free, the
enabled_functions shows that the schedule_timeout was attached again. This
is because it was still left in the fprobe ops that is used to tell
function graph what functions it wants callbacks from.
Cc: stable@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250220202055.393254452@goodmis.org
Fixes: 4346ba1604 ("fprobe: Rewrite fprobe on function-graph tracer")
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Check if a function is already in the manager ops of a subops. A manager
ops contains multiple subops, and if two or more subops are tracing the
same function, the manager ops only needs a single entry in its hash.
Cc: stable@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250220202055.226762894@goodmis.org
Fixes: 4f554e9556 ("ftrace: Add ftrace_set_filter_ips function")
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Function graph uses a subops and manager ops mechanism to attach to
ftrace. The manager ops connects to ftrace and the functions it connects
to is defined by a list of subops that it manages.
The function hash that defines what the above ops attaches to limits the
functions to attach if the hash has any content. If the hash is empty, it
means to trace all functions.
The creation of the manager ops hash is done by iterating over all the
subops hashes. If any of the subops hashes is empty, it means that the
manager ops hash must trace all functions as well.
The issue is in the creation of the manager ops. When a second subops is
attached, a new hash is created by starting it as NULL and adding the
subops one at a time. But the NULL ops is mistaken as an empty hash, and
once an empty hash is found, it stops the loop of subops and just enables
all functions.
# echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# echo "f:myevent2 schedule_timeout" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
trace_initcall_start_cb (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
run_init_process (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
try_to_run_init_process (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
x86_pmu_show_pmu_cap (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
cleanup_rapl_pmus (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
uncore_free_pcibus_map (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
uncore_types_exit (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
uncore_pci_exit.part.0 (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
kvm_shutdown (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
vmx_dump_msrs (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
vmx_cleanup_l1d_flush (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
[..]
Fix this by initializing the new hash to NULL and if the hash is NULL do
not treat it as an empty hash but instead allocate by copying the content
of the first sub ops. Then on subsequent iterations, the new hash will not
be NULL, but the content of the previous subops. If that first subops
attached to all functions, then new hash may assume that the manager ops
also needs to attach to all functions.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250220202055.060300046@goodmis.org
Fixes: 5fccc7552c ("ftrace: Add subops logic to allow one ops to manage many")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
bpf_send_signal_common() uses preemptible() to check whether or not the
current context is preemptible. If it is preemptible, it will use
irq_work to send the signal asynchronously instead of trying to hold a
spin-lock, because spin-lock is sleepable under PREEMPT_RT.
However, preemptible() depends on CONFIG_PREEMPT_COUNT. When
CONFIG_PREEMPT_COUNT is turned off (e.g., CONFIG_PREEMPT_VOLUNTARY=y),
!preemptible() will be evaluated as 1 and bpf_send_signal_common() will
use irq_work unconditionally.
Fix it by unfolding "!preemptible()" and using "preempt_count() != 0 ||
irqs_disabled()" instead.
Fixes: 87c544108b ("bpf: Send signals asynchronously if !preemptible")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20250220042259.1583319-1-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The amount of memory that ftrace uses to save the descriptors to manage
the functions it can trace is shown at output. But if there are a lot of
functions that are skipped because they were weak or the architecture
added holes into the tables, then the extra pages that were allocated are
freed. But these freed pages are not reflected in the numbers shown, and
they can even be inconsistent with what is reported:
ftrace: allocating 57482 entries in 225 pages
ftrace: allocated 224 pages with 3 groups
The above shows the number of original entries that are in the mcount_loc
section and the pages needed to save them (225), but the second output
reflects the number of pages that were actually used. The two should be
consistent as:
ftrace: allocating 56739 entries in 224 pages
ftrace: allocated 224 pages with 3 groups
The above also shows the accurate number of entires that were actually
stored and does not include the entries that were removed.
Cc: bpf <bpf@vger.kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Zheng Yejian <zhengyejian1@huawei.com>
Cc: Martin Kelly <martin.kelly@crowdstrike.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250218200023.221100846@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Now that weak functions turn into skipped entries, update the check to
make sure the amount that was allocated would fit both the entries that
were allocated as well as those that were skipped.
Cc: bpf <bpf@vger.kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Zheng Yejian <zhengyejian1@huawei.com>
Cc: Martin Kelly <martin.kelly@crowdstrike.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250218200023.055162048@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When a function is annotated as "weak" and is overridden, the code is not
removed. If it is traced, the fentry/mcount location in the weak function
will be referenced by the "__mcount_loc" section. This will then be added
to the available_filter_functions list. Since only the address of the
functions are listed, to find the name to show, a search of kallsyms is
used.
Since kallsyms will return the function by simply finding the function
that the address is after but before the next function, an address of a
weak function will show up as the function before it. This is because
kallsyms does not save names of weak functions. This has caused issues in
the past, as now the traced weak function will be listed in
available_filter_functions with the name of the function before it.
At best, this will cause the previous function's name to be listed twice.
At worse, if the previous function was marked notrace, it will now show up
as a function that can be traced. Note that it only shows up that it can
be traced but will not be if enabled, which causes confusion.
https://lore.kernel.org/all/20220412094923.0abe90955e5db486b7bca279@kernel.org/
The commit b39181f7c6 ("ftrace: Add FTRACE_MCOUNT_MAX_OFFSET to avoid
adding weak function") was a workaround to this by checking the function
address before printing its name. If the address was too far from the
function given by the name then instead of printing the name it would
print: __ftrace_invalid_address___<invalid-offset>
The real issue is that these invalid addresses are listed in the ftrace
table look up which available_filter_functions is derived from. A place
holder must be listed in that file because set_ftrace_filter may take a
series of indexes into that file instead of names to be able to do O(1)
lookups to enable filtering (many tools use this method).
Even if kallsyms saved the size of the function, it does not remove the
need of having these place holders. The real solution is to not add a weak
function into the ftrace table in the first place.
To solve this, the sorttable.c code that sorts the mcount regions during
the build is modified to take a "nm -S vmlinux" input, sort it, and any
function listed in the mcount_loc section that is not within a boundary of
the function list given by nm is considered a weak function and is zeroed
out.
Note, this does not mean they will remain zero when booting as KASLR
will still shift those addresses. To handle this, the entries in the
mcount_loc section will be ignored if they are zero or match the
kaslr_offset() value.
Before:
~# grep __ftrace_invalid_address___ /sys/kernel/tracing/available_filter_functions | wc -l
551
After:
~# grep __ftrace_invalid_address___ /sys/kernel/tracing/available_filter_functions | wc -l
0
Cc: bpf <bpf@vger.kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Zheng Yejian <zhengyejian1@huawei.com>
Cc: Martin Kelly <martin.kelly@crowdstrike.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250218200022.883095980@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmeyYIQeHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGNy0H/jWdgjddRaEHQ1RB
e18Oi6MJcTQikHbCHKGZGlyxR4dYxdAONuMmWwgt+266K8qUJSZcNXePwqGEWjx2
qkJ9Tu0Agr8KkfVDtGHGXyd4tuZRpx9Fco6+jKkKiMjjtif7nrUajUGGwRsqGoib
YYzrhbjNZDl17/J58O1E4YZs3w7Lu26PwDR58RZMsSG0pygAfU2fogKcYmi1pTYV
w86icn0LlO8b5Y7fsrY56rLrawnI1RGlxfylUTHzo4QkoIUGvQLB8c6XPMYsVf9R
lvkphu+/fGVnSw577WlVy8DTBso+Pj2nWw4jUTiEAy9hYY6zMxrqrX3XowAwbxj1
m6zP+F8=
=ieVA
-----END PGP SIGNATURE-----
Merge tag 'v6.14-rc3' into x86/core, to pick up fixes
Pick up upstream x86 fixes before applying new patches.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.
Replace hrtimer_init() and the open coded initialization of
hrtimer::function with the new setup mechanism.
Patch was created by using Coccinelle.
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/all/ff8e6e11df5f928b2b97619ac847b4fa045376a1.1738746821.git.namcao@linutronix.de
The pages_touched field represents the number of subbuffers in the ring
buffer that have content that can be read. This is used in accounting of
"dirty_pages" and "buffer_percent" to allow the user to wait for the
buffer to be filled to a certain amount before it reads the buffer in
blocking mode.
The persistent buffer never updated this value so it was set to zero, and
this accounting would take it as it had no content. This would cause user
space to wait for content even though there's enough content in the ring
buffer that satisfies the buffer_percent.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250214123512.0631436e@gandalf.local.home
Fixes: 5f3b6e839f ("ring-buffer: Validate boot range memory events")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When trying to mmap a trace instance buffer that is attached to
reserve_mem, it would crash:
BUG: unable to handle page fault for address: ffffe97bd00025c8
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 2862f3067 P4D 2862f3067 PUD 0
Oops: Oops: 0000 [#1] PREEMPT_RT SMP PTI
CPU: 4 UID: 0 PID: 981 Comm: mmap-rb Not tainted 6.14.0-rc2-test-00003-g7f1a5e3fbf9e-dirty #233
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:validate_page_before_insert+0x5/0xb0
Code: e2 01 89 d0 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 <48> 8b 46 08 a8 01 75 67 66 90 48 89 f0 8b 50 34 85 d2 74 76 48 89
RSP: 0018:ffffb148c2f3f968 EFLAGS: 00010246
RAX: ffff9fa5d3322000 RBX: ffff9fa5ccff9c08 RCX: 00000000b879ed29
RDX: ffffe97bd00025c0 RSI: ffffe97bd00025c0 RDI: ffff9fa5ccff9c08
RBP: ffffb148c2f3f9f0 R08: 0000000000000004 R09: 0000000000000004
R10: 0000000000000000 R11: 0000000000000200 R12: 0000000000000000
R13: 00007f16a18d5000 R14: ffff9fa5c48db6a8 R15: 0000000000000000
FS: 00007f16a1b54740(0000) GS:ffff9fa73df00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffe97bd00025c8 CR3: 00000001048c6006 CR4: 0000000000172ef0
Call Trace:
<TASK>
? __die_body.cold+0x19/0x1f
? __die+0x2e/0x40
? page_fault_oops+0x157/0x2b0
? search_module_extables+0x53/0x80
? validate_page_before_insert+0x5/0xb0
? kernelmode_fixup_or_oops.isra.0+0x5f/0x70
? __bad_area_nosemaphore+0x16e/0x1b0
? bad_area_nosemaphore+0x16/0x20
? do_kern_addr_fault+0x77/0x90
? exc_page_fault+0x22b/0x230
? asm_exc_page_fault+0x2b/0x30
? validate_page_before_insert+0x5/0xb0
? vm_insert_pages+0x151/0x400
__rb_map_vma+0x21f/0x3f0
ring_buffer_map+0x21b/0x2f0
tracing_buffers_mmap+0x70/0xd0
__mmap_region+0x6f0/0xbd0
mmap_region+0x7f/0x130
do_mmap+0x475/0x610
vm_mmap_pgoff+0xf2/0x1d0
ksys_mmap_pgoff+0x166/0x200
__x64_sys_mmap+0x37/0x50
x64_sys_call+0x1670/0x1d70
do_syscall_64+0xbb/0x1d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The reason was that the code that maps the ring buffer pages to user space
has:
page = virt_to_page((void *)cpu_buffer->subbuf_ids[s]);
And uses that in:
vm_insert_pages(vma, vma->vm_start, pages, &nr_pages);
But virt_to_page() does not work with vmap()'d memory which is what the
persistent ring buffer has. It is rather trivial to allow this, but for
now just disable mmap() of instances that have their ring buffer from the
reserve_mem option.
If an mmap() is performed on a persistent buffer it will return -ENODEV
just like it would if the .mmap field wasn't defined in the
file_operations structure.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250214115547.0d7287d3@gandalf.local.home
Fixes: 9b7bdf6f6e ("tracing: Have trace_printk not use binary prints if boot buffer")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The meta data for a mapped ring buffer contains an array of indexes of all
the subbuffers. The first entry is the reader page, and the rest of the
entries lay out the order of the subbuffers in how the ring buffer link
list is to be created.
The validator currently makes sure that all the entries are within the
range of 0 and nr_subbufs. But it does not check if there are any
duplicates.
While working on the ring buffer, I corrupted this array, where I added
duplicates. The validator did not catch it and created the ring buffer
link list on top of it. Luckily, the corruption was only that the reader
page was also in the writer path and only presented corrupted data but did
not crash the kernel. But if there were duplicates in the writer side,
then it could corrupt the ring buffer link list and cause a crash.
Create a bitmask array with the size of the number of subbuffers. Then
clear it. When walking through the subbuf array checking to see if the
entries are within the range, test if its bit is already set in the
subbuf_mask. If it is, then there is duplicates and fail the validation.
If not, set the corresponding bit and continue.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250214102820.7509ddea@gandalf.local.home
Fixes: c76883f18e ("ring-buffer: Add test if range of boot buffer is valid")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently if __tracing_resize_ring_buffer() returns an error, the
tracing_resize_ringbuffer() returns -ENOMEM. But it may not be a memory
issue that caused the function to fail. If the ring buffer is memory
mapped, then the resizing of the ring buffer will be disabled. But if the
user tries to resize the buffer, it will get an -ENOMEM returned, which is
confusing because there is plenty of memory. The actual error returned was
-EBUSY, which would make much more sense to the user.
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250213134132.7e4505d7@gandalf.local.home
Fixes: 117c39200d ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Memory mapping the tracing ring buffer will disable resizing the buffer.
But if there's an error in the memory mapping like an invalid parameter,
the function exits out without re-enabling the resizing of the ring
buffer, preventing the ring buffer from being resized after that.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250213131957.530ec3c5@gandalf.local.home
Fixes: 117c39200d ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pretty much every caller of is_endbr() actually wants to test something at an
address and ends up doing get_kernel_nofault(). Fold the lot into a more
convenient helper.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20250207122546.181367417@infradead.org
The code was restructured where the function graph notrace code, that
would not trace a function and all its children is done by setting a
NOTRACE flag when the function that is not to be traced is hit.
There's a TRACE_GRAPH_NOTRACE_BIT which defines the bit in the flags and a
TRACE_GRAPH_NOTRACE which is the mask with that bit set. But the
restructuring used TRACE_GRAPH_NOTRACE_BIT when it should have used
TRACE_GRAPH_NOTRACE.
For example:
# cd /sys/kernel/tracing
# echo set_track_prepare stack_trace_save > set_graph_notrace
# echo function_graph > current_tracer
# cat trace
[..]
0) | __slab_free() {
0) | free_to_partial_list() {
0) | arch_stack_walk() {
0) | __unwind_start() {
0) 0.501 us | get_stack_info();
Where a non filter trace looks like:
# echo > set_graph_notrace
# cat trace
0) | free_to_partial_list() {
0) | set_track_prepare() {
0) | stack_trace_save() {
0) | arch_stack_walk() {
0) | __unwind_start() {
Where the filter should look like:
# cat trace
0) | free_to_partial_list() {
0) | _raw_spin_lock_irqsave() {
0) 0.350 us | preempt_count_add();
0) 0.351 us | do_raw_spin_lock();
0) 2.440 us | }
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250208001511.535be150@batman.local.home
Fixes: b84214890a ("function_graph: Move graph notrace bit to shadow stack global var")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add the const qualifier to all the ctl_tables in the tree except for
watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls,
loadpin_sysctl_table and the ones calling register_net_sysctl (./net,
drivers/inifiniband dirs). These are special cases as they use a
registration function with a non-const qualified ctl_table argument or
modify the arrays before passing them on to the registration function.
Constifying ctl_table structs will prevent the modification of
proc_handler function pointers as the arrays would reside in .rodata.
This is made possible after commit 78eb4ea25c ("sysctl: treewide:
constify the ctl_table argument of proc_handlers") constified all the
proc_handlers.
Created this by running an spatch followed by a sed command:
Spatch:
virtual patch
@
depends on !(file in "net")
disable optional_qualifier
@
identifier table_name != {
watchdog_hardlockup_sysctl,
iwcm_ctl_table,
ucma_ctl_table,
memory_allocation_profiling_sysctls,
loadpin_sysctl_table
};
@@
+ const
struct ctl_table table_name [] = { ... };
sed:
sed --in-place \
-e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \
kernel/utsname_sysctl.c
Reviewed-by: Song Liu <song@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> # for kernel/trace/
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> # SCSI
Reviewed-by: Darrick J. Wong <djwong@kernel.org> # xfs
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Bill O'Donnell <bodonnel@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Joel Granados <joel.granados@kernel.org>
- Add a test suite to test the tool
Add a small test suite that can be used to test rtla's basic features to
at least have something to test when applying changes.
- Automate manual steps in monitor creation
While creating a new monitor in RV, besides generating code from dot2k,
there are a few manual steps which can be tedious and error prone, like
adding the tracepoints, makefile lines and kconfig, or selecting events
that start the monitor in the initial state.
Updates were made to try and automate as much as possible among those steps to
make creating a new RV monitor much quicker. It is still requires to
select proper tracepoints, this step is harder to automate in a general
way and, in several cases, would still need user intervention.
- Have rtla timerlat hist and top set OSNOISE_WORKLOAD flag
Have both rtla-timerlat-hist and rtla-timerlat-top set OSNOISE_WORKLOAD to
the proper value ("on" when running with -k, "off" when running with -u)
every time the option is available instead of setting it only when running
with -u.
This prevents rtla timerlat -k from giving no results when
NO_OSNOISE_WORKLOAD is set, either manually or by an abnormally exited earlier
run of rtla timerlat -u.
- Stop rtla timerlat on signal properly when overloaded
There is an issue where if rtla is run on machines with a high number of
CPUs (100+), timerlat can generate more samples than rtla is able to process
via tracefs_iterate_raw_events. This is especially common when the interval
is set to 100us (rteval and cyclictest default) as opposed to the rtla
default of 1000us, but also happens with the rtla default.
Currently, this leads to rtla hanging and having to be terminated with
SIGTERM. SIGINT setting stop_tracing is not enough, since more and more
events are coming and tracefs_iterate_raw_events never exits.
To fix this: Stop the timerlat tracer on SIGINT/SIGALRM to ensure no more
events are generated when rtla is supposed to exit.
Also on receiving SIGINT/SIGALRM twice, abort iteration immediately with
tracefs_iterate_stop, making rtla exit right away instead of waiting for all
events to be processed.
- Account for missed events
Due to tracefs buffer overflow, it can happen that rtla misses events,
making the tracing results inaccurate.
Count both the number of missed events and the total number of processed
events, and display missed events as well as their percentage. The numbers
are displayed for both osnoise and timerlat, even though for the earlier,
missed events are generally not expected.
For hist, the number is displayed at the end of the run; for top, it is
displayed on each printing of the top table.
- Changes to make osnoise more robust
There was a dependency in the code that the first field of the
osnoise_tool structure was the trace field. If that that ever changed,
then the code work break. Change the code to encapsulate this dependency
where the code that uses the structure does not have this dependency.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ5UQ4BQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qktFAQD2px6MyoOVTssB5Iw3aTWGUfTFoDEc
bfng5JsBxlVJkQEA+2UUvP8FJlLTOQvVEwJiscX7CCJxl5bYkV6GWuGRxQU=
=h//9
-----END PGP SIGNATURE-----
Merge tag 'trace-tools-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull rv and tools/rtla updates from Steven Rostedt:
- Add a test suite to test the tool
Add a small test suite that can be used to test rtla's basic features
to at least have something to test when applying changes.
- Automate manual steps in monitor creation
While creating a new monitor in RV, besides generating code from
dot2k, there are a few manual steps which can be tedious and error
prone, like adding the tracepoints, makefile lines and kconfig, or
selecting events that start the monitor in the initial state.
Updates were made to try and automate as much as possible among those
steps to make creating a new RV monitor much quicker. It is still
requires to select proper tracepoints, this step is harder to
automate in a general way and, in several cases, would still need
user intervention.
- Have rtla timerlat hist and top set OSNOISE_WORKLOAD flag
Have both rtla-timerlat-hist and rtla-timerlat-top set
OSNOISE_WORKLOAD to the proper value ("on" when running with -k,
"off" when running with -u) every time the option is available
instead of setting it only when running with -u.
This prevents rtla timerlat -k from giving no results when
NO_OSNOISE_WORKLOAD is set, either manually or by an abnormally
exited earlier run of rtla timerlat -u.
- Stop rtla timerlat on signal properly when overloaded
There is an issue where if rtla is run on machines with a high number
of CPUs (100+), timerlat can generate more samples than rtla is able
to process via tracefs_iterate_raw_events. This is especially common
when the interval is set to 100us (rteval and cyclictest default) as
opposed to the rtla default of 1000us, but also happens with the rtla
default.
Currently, this leads to rtla hanging and having to be terminated
with SIGTERM. SIGINT setting stop_tracing is not enough, since more
and more events are coming and tracefs_iterate_raw_events never
exits.
To fix this: Stop the timerlat tracer on SIGINT/SIGALRM to ensure no
more events are generated when rtla is supposed to exit.
Also on receiving SIGINT/SIGALRM twice, abort iteration immediately
with tracefs_iterate_stop, making rtla exit right away instead of
waiting for all events to be processed.
- Account for missed events
Due to tracefs buffer overflow, it can happen that rtla misses
events, making the tracing results inaccurate.
Count both the number of missed events and the total number of
processed events, and display missed events as well as their
percentage. The numbers are displayed for both osnoise and timerlat,
even though for the earlier, missed events are generally not
expected.
For hist, the number is displayed at the end of the run; for top, it
is displayed on each printing of the top table.
- Changes to make osnoise more robust
There was a dependency in the code that the first field of the
osnoise_tool structure was the trace field. If that that ever
changed, then the code work break. Change the code to encapsulate
this dependency where the code that uses the structure does not have
this dependency.
* tag 'trace-tools-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (22 commits)
rtla: Report missed event count
rtla: Add function to report missed events
rtla: Count all processed events
rtla: Count missed trace events
tools/rtla: Add osnoise_trace_is_off()
rtla/timerlat_top: Set OSNOISE_WORKLOAD for kernel threads
rtla/timerlat_hist: Set OSNOISE_WORKLOAD for kernel threads
rtla/osnoise: Distinguish missing workload option
rtla/timerlat_top: Abort event processing on second signal
rtla/timerlat_hist: Abort event processing on second signal
rtla/timerlat_top: Stop timerlat tracer on signal
rtla/timerlat_hist: Stop timerlat tracer on signal
rtla: Add trace_instance_stop
tools/rtla: Add basic test suite
verification/dot2k: Implement event type detection
verification/dot2k: Auto patch current kernel source
verification/dot2k: Simplify manual steps in monitor creation
rv: Simplify manual steps in monitor creation
verification/dot2k: Add support for name and description options
verification/dot2k: More robust template variables
...
- Reset idle tasks on reset for runtime verifier
When the runtime verifier is reset, it resets the task's data that is being
monitored. But it only iterates for_each_process() which does not include
the idle tasks. As the idle tasks can be monitored, they need to be reset
as well.
- Fix the enabling and disabling of tracepoints in osnoise
If timerlat is enabled and the WORKLOAD flag is not set, then the osnoise
tracer will enable the migrate task tracepoint to monitor it for its own
workload. The test to enable the tracepoint is done against user space
modifiable parameters. On disabling of the tracer, those same parameters
are used to determine if the tracepoint should be disabled. The problem is
if user space were to modify the parameters after it enables the tracer
then it may not disable the tracepoint.
Instead, a static variable is used to keep track if the tracepoint was
enabled or not. Then when the tracer shuts down, it will use this variable
to decide to disable the tracepoint or not, instead of looking at the user
space parameters.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ5UJ1BQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qo46AQDjr1yVTyUmzvxe1bMLDoDOq1xeRMRe
4f8CdpOJRxbi0QEAwnl5Ey9Rvcuy8GFpt/USESr4VYWAN10fvsPx7pkphAs=
=RYyn
-----END PGP SIGNATURE-----
Merge tag 'trace-rv-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull runtime verifier and osnoise fixes from Steven Rostedt:
- Reset idle tasks on reset for runtime verifier
When the runtime verifier is reset, it resets the task's data that is
being monitored. But it only iterates for_each_process() which does
not include the idle tasks. As the idle tasks can be monitored, they
need to be reset as well.
- Fix the enabling and disabling of tracepoints in osnoise
If timerlat is enabled and the WORKLOAD flag is not set, then the
osnoise tracer will enable the migrate task tracepoint to monitor it
for its own workload. The test to enable the tracepoint is done
against user space modifiable parameters. On disabling of the tracer,
those same parameters are used to determine if the tracepoint should
be disabled. The problem is if user space were to modify the
parameters after it enables the tracer then it may not disable the
tracepoint.
Instead, a static variable is used to keep track if the tracepoint
was enabled or not. Then when the tracer shuts down, it will use this
variable to decide to disable the tracepoint or not, instead of
looking at the user space parameters.
* tag 'trace-rv-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/osnoise: Fix resetting of tracepoints
rv: Reset per-task monitors also for idle tasks
If a timerlat tracer is started with the osnoise option OSNOISE_WORKLOAD
disabled, but then that option is enabled and timerlat is removed, the
tracepoints that were enabled on timerlat registration do not get
disabled. If the option is disabled again and timelat is started, then it
triggers a warning in the tracepoint code due to registering the
tracepoint again without ever disabling it.
Do not use the same user space defined options to know to disable the
tracepoints when timerlat is removed. Instead, set a global flag when it
is enabled and use that flag to know to disable the events.
~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options
~# echo timerlat > /sys/kernel/tracing/current_tracer
~# echo OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options
~# echo nop > /sys/kernel/tracing/current_tracer
~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options
~# echo timerlat > /sys/kernel/tracing/current_tracer
Triggers:
------------[ cut here ]------------
WARNING: CPU: 6 PID: 1337 at kernel/tracepoint.c:294 tracepoint_add_func+0x3b6/0x3f0
Modules linked in:
CPU: 6 UID: 0 PID: 1337 Comm: rtla Not tainted 6.13.0-rc4-test-00018-ga867c441128e-dirty #73
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:tracepoint_add_func+0x3b6/0x3f0
Code: 48 8b 53 28 48 8b 73 20 4c 89 04 24 e8 23 59 11 00 4c 8b 04 24 e9 36 fe ff ff 0f 0b b8 ea ff ff ff 45 84 e4 0f 84 68 fe ff ff <0f> 0b e9 61 fe ff ff 48 8b 7b 18 48 85 ff 0f 84 4f ff ff ff 49 8b
RSP: 0018:ffffb9b003a87ca0 EFLAGS: 00010202
RAX: 00000000ffffffef RBX: ffffffff92f30860 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff9bf59e91ccd0 RDI: ffffffff913b6410
RBP: 000000000000000a R08: 00000000000005c7 R09: 0000000000000002
R10: ffffb9b003a87ce0 R11: 0000000000000002 R12: 0000000000000001
R13: ffffb9b003a87ce0 R14: ffffffffffffffef R15: 0000000000000008
FS: 00007fce81209240(0000) GS:ffff9bf6fdd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e99b728000 CR3: 00000001277c0002 CR4: 0000000000172ef0
Call Trace:
<TASK>
? __warn.cold+0xb7/0x14d
? tracepoint_add_func+0x3b6/0x3f0
? report_bug+0xea/0x170
? handle_bug+0x58/0x90
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? __pfx_trace_sched_migrate_callback+0x10/0x10
? tracepoint_add_func+0x3b6/0x3f0
? __pfx_trace_sched_migrate_callback+0x10/0x10
? __pfx_trace_sched_migrate_callback+0x10/0x10
tracepoint_probe_register+0x78/0xb0
? __pfx_trace_sched_migrate_callback+0x10/0x10
osnoise_workload_start+0x2b5/0x370
timerlat_tracer_init+0x76/0x1b0
tracing_set_tracer+0x244/0x400
tracing_set_trace_write+0xa0/0xe0
vfs_write+0xfc/0x570
? do_sys_openat2+0x9c/0xe0
ksys_write+0x72/0xf0
do_syscall_64+0x79/0x1c0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250123204159.4450c88e@gandalf.local.home
Fixes: e88ed227f6 ("tracing/timerlat: Add user-space interface")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Have emulating atomic64 use arch_spin_locks instead of raw_spin_locks
The tracing ring buffer events have a small timestamp that holds the
delta between itself and the event before it. But this can be tricky
to update when interrupts come in. It originally just set the deltas
to zero for events that interrupted the adding of another event which
made all the events in the interrupt have the same timestamp as the
event it interrupted. This was not suitable for many tools, so it
was eventually fixed. But that fix required adding an atomic64 cmpxchg
on the timestamp in cases where an event was added while another
event was in the process of being added.
Originally, for 32 bit architectures, the manipulation of the 64 bit
timestamp was done by a structure that held multiple 32bit words to hold
parts of the timestamp and a counter. But as updates to the ring buffer
were done, maintaining this became too complex and was replaced by the
atomic64 generic operations which are now used by both 64bit and 32bit
architectures. Shortly after that, it was reported that riscv32 and
other 32 bit architectures that just used the generic atomic64 were
locking up. This was because the generic atomic64 operations defined in
lib/atomic64.c uses a raw_spin_lock() to emulate an atomic64 operation.
The problem here was that raw_spin_lock() can also be traced by the
function tracer (which is commonly used for debugging raw spin locks).
Since the function tracer uses the tracing ring buffer, which now is being
traced internally, this was triggering a recursion and setting off a
warning that the spin locks were recusing.
There's no reason for the code that emulates atomic64 operations to be
using raw_spin_locks which have a lot of debugging infrastructure attached
to them (depending on the config options). Instead it should be using
the arch_spin_lock() which does not have any infrastructure attached to
them and is used by low level infrastructure like RCU locks, lockdep
and of course tracing. Using arch_spin_lock()s fixes this issue.
- Do not trace in NMI if the architecture uses emulated atomic64 operations
Another issue with using the emulated atomic64 operations that uses
spin locks to emulate the atomic64 operations is that they cannot be
used in NMI context. As an NMI can trigger while holding the atomic64
spin locks it can try to take the same lock and cause a deadlock.
Have the ring buffer fail recording events if in NMI context and the
architecture uses the emulated atomic64 operations.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ5Jr7RQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qg7cAPoD/H4BRsFa3UUDnxofTlBuj4A7neJd
rk9ddD9HXH8KywEAhBn1Oujiw81Ayjx7E6s4ednAQX4rldTXBXDyFNuuGgU=
=b13F
-----END PGP SIGNATURE-----
Merge tag 'trace-ringbuffer-v6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull trace fing buffer fix from Steven Rostedt:
"Fix atomic64 operations on some architectures for the tracing ring
buffer:
- Have emulating atomic64 use arch_spin_locks instead of
raw_spin_locks
The tracing ring buffer events have a small timestamp that holds
the delta between itself and the event before it. But this can be
tricky to update when interrupts come in. It originally just set
the deltas to zero for events that interrupted the adding of
another event which made all the events in the interrupt have the
same timestamp as the event it interrupted. This was not suitable
for many tools, so it was eventually fixed. But that fix required
adding an atomic64 cmpxchg on the timestamp in cases where an event
was added while another event was in the process of being added.
Originally, for 32 bit architectures, the manipulation of the 64
bit timestamp was done by a structure that held multiple 32bit
words to hold parts of the timestamp and a counter. But as updates
to the ring buffer were done, maintaining this became too complex
and was replaced by the atomic64 generic operations which are now
used by both 64bit and 32bit architectures. Shortly after that, it
was reported that riscv32 and other 32 bit architectures that just
used the generic atomic64 were locking up. This was because the
generic atomic64 operations defined in lib/atomic64.c uses a
raw_spin_lock() to emulate an atomic64 operation. The problem here
was that raw_spin_lock() can also be traced by the function tracer
(which is commonly used for debugging raw spin locks). Since the
function tracer uses the tracing ring buffer, which now is being
traced internally, this was triggering a recursion and setting off
a warning that the spin locks were recusing.
There's no reason for the code that emulates atomic64 operations to
be using raw_spin_locks which have a lot of debugging
infrastructure attached to them (depending on the config options).
Instead it should be using the arch_spin_lock() which does not have
any infrastructure attached to them and is used by low level
infrastructure like RCU locks, lockdep and of course tracing. Using
arch_spin_lock()s fixes this issue.
- Do not trace in NMI if the architecture uses emulated atomic64
operations
Another issue with using the emulated atomic64 operations that uses
spin locks to emulate the atomic64 operations is that they cannot
be used in NMI context. As an NMI can trigger while holding the
atomic64 spin locks it can try to take the same lock and cause a
deadlock.
Have the ring buffer fail recording events if in NMI context and
the architecture uses the emulated atomic64 operations"
* tag 'trace-ringbuffer-v6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
atomic64: Use arch_spin_locks instead of raw_spin_locks
ring-buffer: Do not allow events in NMI with generic atomic64 cmpxchg()
The calltime and rettime were used by the function graph tracer to
calculate the timings of functions where it traced their entry and exit.
The calltime and rettime were stored in the generic structures that
were used for the mechanisms to add an entry and exit callback.
Now that function graph infrastructure is used by other subsystems than
just the tracer, the calltime and rettime are not needed for them.
Remove the calltime and rettime from the generic fgraph infrastructure
and have the callers that require them handle them.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ5Jk2BQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qr3GAQCtzSX6PYTliZKm/Wa5zhebopwhGKEb
Mv0VZejaxYu0hgEA5O57J676FAOaQ7BLzoMojKFhR8RZ6LadKR5r7A0Qzgc=
=Bb/r
-----END PGP SIGNATURE-----
Merge tag 'ftrace-v6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull fgraph updates from Steven Rostedt:
"Remove calltime and rettime from fgraph infrastructure
The calltime and rettime were used by the function graph tracer to
calculate the timings of functions where it traced their entry and
exit. The calltime and rettime were stored in the generic structures
that were used for the mechanisms to add an entry and exit callback.
Now that function graph infrastructure is used by other subsystems
than just the tracer, the calltime and rettime are not needed for
them. Remove the calltime and rettime from the generic fgraph
infrastructure and have the callers that require them handle them"
* tag 'ftrace-v6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
fgraph: Remove calltime and rettime from generic operations
- Cleanup with guard() and free() helpers
There were several places in the code that had a lot of "goto out" in the
error paths to either unlock a lock or free some memory that was
allocated. But this is error prone. Convert the code over to use the
guard() and free() helpers that let the compiler unlock locks or free
memory when the function exits.
- Update the Rust tracepoint code to use the C code too
There was some duplication of the tracepoint code for Rust that did the
same logic as the C code. Add a helper that makes it possible for both
algorithms to use the same logic in one place.
- Add poll to trace event hist files
It is useful to know when an event is triggered, or even with some
filtering. Since hist files of events get updated when active and the
event is triggered, allow applications to poll the hist file and wake up
when an event is triggered. This will let the application know that the
event it is waiting for happened.
- Add :mod: command to enable events for current or future modules
The function tracer already has a way to enable functions to be traced in
modules by writing ":mod:<module>" into set_ftrace_filter. That will
enable either all the functions for the module if it is loaded, or if it
is not, it will cache that command, and when the module is loaded that
matches <module>, its functions will be enabled. This also allows init
functions to be traced. But currently events do not have that feature.
Add the command where if ':mod:<module>' is written into set_event, then
either all the modules events are enabled if it is loaded, or cache it so
that the module's events are enabled when it is loaded. This also works
from the kernel command line, where "trace_event=:mod:<module>", when the
module is loaded at boot up, its events will be enabled then.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ5EbMxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qkZsAP9Amgx9frSbR1pn1t0I3wVnQx7khgOu
s/b8Ro+vjTx1/QD/RN2AA7f+HK4F27w3Aqfrs0nKXAPtXWsJ9Epp8raG5w8=
=Pg+4
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing updates from Steven Rostedt:
- Cleanup with guard() and free() helpers
There were several places in the code that had a lot of "goto out" in
the error paths to either unlock a lock or free some memory that was
allocated. But this is error prone. Convert the code over to use the
guard() and free() helpers that let the compiler unlock locks or free
memory when the function exits.
- Update the Rust tracepoint code to use the C code too
There was some duplication of the tracepoint code for Rust that did
the same logic as the C code. Add a helper that makes it possible for
both algorithms to use the same logic in one place.
- Add poll to trace event hist files
It is useful to know when an event is triggered, or even with some
filtering. Since hist files of events get updated when active and the
event is triggered, allow applications to poll the hist file and wake
up when an event is triggered. This will let the application know
that the event it is waiting for happened.
- Add :mod: command to enable events for current or future modules
The function tracer already has a way to enable functions to be
traced in modules by writing ":mod:<module>" into set_ftrace_filter.
That will enable either all the functions for the module if it is
loaded, or if it is not, it will cache that command, and when the
module is loaded that matches <module>, its functions will be
enabled. This also allows init functions to be traced. But currently
events do not have that feature.
Add the command where if ':mod:<module>' is written into set_event,
then either all the modules events are enabled if it is loaded, or
cache it so that the module's events are enabled when it is loaded.
This also works from the kernel command line, where
"trace_event=:mod:<module>", when the module is loaded at boot up,
its events will be enabled then.
* tag 'trace-v6.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (26 commits)
tracing: Fix output of set_event for some cached module events
tracing: Fix allocation of printing set_event file content
tracing: Rename update_cache() to update_mod_cache()
tracing: Fix #if CONFIG_MODULES to #ifdef CONFIG_MODULES
selftests/ftrace: Add test that tests event :mod: commands
tracing: Cache ":mod:" events for modules not loaded yet
tracing: Add :mod: command to enabled module events
selftests/tracing: Add hist poll() support test
tracing/hist: Support POLLPRI event for poll on histogram
tracing/hist: Add poll(POLLIN) support on hist file
tracing: Fix using ret variable in tracing_set_tracer()
tracepoint: Reduce duplication of __DO_TRACE_CALL
tracing/string: Create and use __free(argv_free) in trace_dynevent.c
tracing: Switch trace_stat.c code over to use guard()
tracing: Switch trace_stack.c code over to use guard()
tracing: Switch trace_osnoise.c code over to use guard() and __free()
tracing: Switch trace_events_synth.c code over to use guard()
tracing: Switch trace_events_filter.c code over to use guard()
tracing: Switch trace_events_trigger.c code over to use guard()
tracing: Switch trace_events_hist.c code over to use guard()
...
- kprobes: Cleanups using guard() and __free(): Use cleanup.h macros
to cleanup code and remove all gotos from kprobes code. This work
includes below changes.
. kprobes: Adopt guard() and scoped_guard()
. jump_label: Define guard() for jump_label_lock
. kprobes: Use guard() for external locks
. kprobes: Use guard for rcu_read_lock
. kprobes: Remove unneeded goto
. kprobes: Remove remaining gotos
- tracing/probes: Also cleanups tracing/*probe events code with guard()
and __free(). These patches are just to simplify the parser codes.
This work includes below changes.
. tracing/kprobe: Adopt guard() and scoped_guard()
. tracing/uprobe: Adopt guard() and scoped_guard()
. tracing/eprobe: Adopt guard() and scoped_guard()
. tracing: Use __free() in trace_probe for cleanup
. tracing: Use __free() for kprobe events to cleanup
. tracing/kprobes: Simplify __trace_kprobe_create() by removing gotos
- kprobes: Reduce preempt disable scope in check_kprobe_access_safe()
This reduces preempt disable time only when getting the module
refcount in check_kprobe_access_safe(). Previously it disabled
preempt needlessly for other checks including
jump_label_text_reserved(), but it took long time because of
the linear search.
-----BEGIN PGP SIGNATURE-----
iQFPBAABCgA5FiEEh7BulGwFlgAOi5DV2/sHvwUrPxsFAmeNy8kbHG1hc2FtaS5o
aXJhbWF0c3VAZ21haWwuY29tAAoJENv7B78FKz8b/UoIAMYX8pYtLMZjokKSlsnN
Y3rMZecFJNKfXeA62YazpESO9n+BYyqj/Zj25Ws4YzdfnoT4kGtMuoUCS7d5U3lo
RZO/a7i3TgrzQdWbRwBz7l75h+FnCAsrSoLGoH/sQxXUP+p/2C6GJG3O3A/0qMaS
TPp7/nsR78P7MSf6Yr/ODZj0UWMSX6a6QNrzwloiMUjY6aPxz7K1on9cdzMF2QPE
fgtJk+JbCn9nLOJi/SVlO+wu4EfdKrfT7sqz9taNX/eQYmx2O9fE3R92Qvhxh79r
MrqcrMfcwfWtX+yD1kb9mf+jMNYy8Dhcf595B0TGSzCZq64ir9UukntR6YD3raAO
Wm0=
=qmrY
-----END PGP SIGNATURE-----
Merge tag 'probes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes updates from Masami Hiramatsu:
- kprobes: Cleanups using guard() and __free(): Use cleanup.h macros to
cleanup code and remove all gotos from kprobes code.
- tracing/probes: Also cleanups tracing/*probe events code with guard()
and __free(). These patches are just to simplify the parser codes.
- kprobes: Reduce preempt disable scope in check_kprobe_access_safe()
This reduces preempt disable time to only when getting the module
refcount in check_kprobe_access_safe().
Previously it disabled preempt needlessly for other checks including
jump_label_text_reserved(), which took a long time because of the
linear search.
* tag 'probes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/kprobes: Simplify __trace_kprobe_create() by removing gotos
tracing: Use __free() for kprobe events to cleanup
tracing: Use __free() in trace_probe for cleanup
kprobes: Remove remaining gotos
kprobes: Remove unneeded goto
kprobes: Use guard for rcu_read_lock
kprobes: Use guard() for external locks
jump_label: Define guard() for jump_label_lock
tracing/eprobe: Adopt guard() and scoped_guard()
tracing/uprobe: Adopt guard() and scoped_guard()
tracing/kprobe: Adopt guard() and scoped_guard()
kprobes: Adopt guard() and scoped_guard()
kprobes: Reduce preempt disable scope in check_kprobe_access_safe()
-----BEGIN PGP SIGNATURE-----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=f2CA
-----END PGP SIGNATURE-----
Merge tag 'bpf-next-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
"A smaller than usual release cycle.
The main changes are:
- Prepare selftest to run with GCC-BPF backend (Ihor Solodrai)
In addition to LLVM-BPF runs the BPF CI now runs GCC-BPF in compile
only mode. Half of the tests are failing, since support for
btf_decl_tag is still WIP, but this is a great milestone.
- Convert various samples/bpf to selftests/bpf/test_progs format
(Alexis Lothoré and Bastien Curutchet)
- Teach verifier to recognize that array lookup with constant
in-range index will always succeed (Daniel Xu)
- Cleanup migrate disable scope in BPF maps (Hou Tao)
- Fix bpf_timer destroy path in PREEMPT_RT (Hou Tao)
- Always use bpf_mem_alloc in bpf_local_storage in PREEMPT_RT (Martin
KaFai Lau)
- Refactor verifier lock support (Kumar Kartikeya Dwivedi)
This is a prerequisite for upcoming resilient spin lock.
- Remove excessive 'may_goto +0' instructions in the verifier that
LLVM leaves when unrolls the loops (Yonghong Song)
- Remove unhelpful bpf_probe_write_user() warning message (Marco
Elver)
- Add fd_array_cnt attribute for prog_load command (Anton Protopopov)
This is a prerequisite for upcoming support for static_branch"
* tag 'bpf-next-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (125 commits)
selftests/bpf: Add some tests related to 'may_goto 0' insns
bpf: Remove 'may_goto 0' instruction in opt_remove_nops()
bpf: Allow 'may_goto 0' instruction in verifier
selftests/bpf: Add test case for the freeing of bpf_timer
bpf: Cancel the running bpf_timer through kworker for PREEMPT_RT
bpf: Free element after unlock in __htab_map_lookup_and_delete_elem()
bpf: Bail out early in __htab_map_lookup_and_delete_elem()
bpf: Free special fields after unlock in htab_lru_map_delete_node()
tools: Sync if_xdp.h uapi tooling header
libbpf: Work around kernel inconsistently stripping '.llvm.' suffix
bpf: selftests: verifier: Add nullness elision tests
bpf: verifier: Support eliding map lookup nullness
bpf: verifier: Refactor helper access type tracking
bpf: tcp: Mark bpf_load_hdr_opt() arg2 as read-write
bpf: verifier: Add missing newline on verbose() call
selftests/bpf: Add distilled BTF test about marking BTF_IS_EMBEDDED
libbpf: Fix incorrect traversal end type ID when marking BTF_IS_EMBEDDED
libbpf: Fix return zero when elf_begin failed
selftests/bpf: Fix btf leak on new btf alloc failure in btf_distill test
veristat: Load struct_ops programs only once
...
The function graph infrastructure is now generic so that kretprobes,
fprobes and BPF can use it. But there is still some leftover logic that
only the function graph tracer itself uses. This is the calculation of the
calltime and return time of the functions. The calculation of the calltime
has been moved into the function graph tracer and those users that need it
so that it doesn't cause overhead to the other users. But the return
function timestamp was still called.
Instead of just moving the taking of the timestamp into the function graph
trace remove the calltime and rettime completely from the ftrace_graph_ret
structure. Instead, move it into the function graph return entry event
structure and this also moves all the calltime and rettime logic out of
the generic fgraph.c code and into the tracing code that uses it.
This has been reported to decrease the overhead by ~27%.
Link: https://lore.kernel.org/all/Z3aSuql3fnXMVMoM@krava/
Link: https://lore.kernel.org/all/173665959558.1629214.16724136597211810729.stgit@devnote2/
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250121194436.15bdf71a@gandalf.local.home
Reported-by: Jiri Olsa <olsajiri@gmail.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Have fprobes built on top of function graph infrastructure
The fprobe logic is an optimized kprobe that uses ftrace to attach to
functions when a probe is needed at the start or end of the function. The
fprobe and kretprobe logic implements a similar method as the function
graph tracer to trace the end of the function. That is to hijack the
return address and jump to a trampoline to do the trace when the function
exits. To do this, a shadow stack needs to be created to store the
original return address. Fprobes and function graph do this slightly
differently. Fprobes (and kretprobes) has slots per callsite that are
reserved to save the return address. This is fine when just a few points
are traced. But users of fprobes, such as BPF programs, are starting to add
many more locations, and this method does not scale.
The function graph tracer was created to trace all functions in the
kernel. In order to do this, when function graph tracing is started, every
task gets its own shadow stack to hold the return address that is going to
be traced. The function graph tracer has been updated to allow multiple
users to use its infrastructure. Now have fprobes be one of those users.
This will also allow for the fprobe and kretprobe methods to trace the
return address to become obsolete. With new technologies like CFI that
need to know about these methods of hijacking the return address, going
toward a solution that has only one method of doing this will make the
kernel less complex.
- Cleanup with guard() and free() helpers
There were several places in the code that had a lot of "goto out" in the
error paths to either unlock a lock or free some memory that was
allocated. But this is error prone. Convert the code over to use the
guard() and free() helpers that let the compiler unlock locks or free
memory when the function exits.
- Remove disabling of interrupts in the function graph tracer
When function graph tracer was first introduced, it could race with
interrupts and NMIs. To prevent that race, it would disable interrupts and
not trace NMIs. But the code has changed to allow NMIs and also
interrupts. This change was done a long time ago, but the disabling of
interrupts was never removed. Remove the disabling of interrupts in the
function graph tracer is it is not needed. This greatly improves its
performance.
- Allow the :mod: command to enable tracing module functions on the kernel
command line.
The function tracer already has a way to enable functions to be traced in
modules by writing ":mod:<module>" into set_ftrace_filter. That will
enable either all the functions for the module if it is loaded, or if it
is not, it will cache that command, and when the module is loaded that
matches <module>, its functions will be enabled. This also allows init
functions to be traced. But currently events do not have that feature.
Because enabling function tracing can be done very early at boot up
(before scheduling is enabled), the commands that can be done when
function tracing is started is limited. Having the ":mod:" command to
trace module functions as they are loaded is very useful. Update the
kernel command line function filtering to allow it.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ42E2RQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qqXSAPwOMxuhye8tb1GYG62QD9+w7e6nOmlC
2GCPj4detnEM2QD/ciivkhespVKhHpZHRewAuSnJgHPSM45NQ3EVESzjWQ4=
=snbx
-----END PGP SIGNATURE-----
Merge tag 'ftrace-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace updates from Steven Rostedt:
- Have fprobes built on top of function graph infrastructure
The fprobe logic is an optimized kprobe that uses ftrace to attach to
functions when a probe is needed at the start or end of the function.
The fprobe and kretprobe logic implements a similar method as the
function graph tracer to trace the end of the function. That is to
hijack the return address and jump to a trampoline to do the trace
when the function exits. To do this, a shadow stack needs to be
created to store the original return address. Fprobes and function
graph do this slightly differently. Fprobes (and kretprobes) has
slots per callsite that are reserved to save the return address. This
is fine when just a few points are traced. But users of fprobes, such
as BPF programs, are starting to add many more locations, and this
method does not scale.
The function graph tracer was created to trace all functions in the
kernel. In order to do this, when function graph tracing is started,
every task gets its own shadow stack to hold the return address that
is going to be traced. The function graph tracer has been updated to
allow multiple users to use its infrastructure. Now have fprobes be
one of those users. This will also allow for the fprobe and kretprobe
methods to trace the return address to become obsolete. With new
technologies like CFI that need to know about these methods of
hijacking the return address, going toward a solution that has only
one method of doing this will make the kernel less complex.
- Cleanup with guard() and free() helpers
There were several places in the code that had a lot of "goto out" in
the error paths to either unlock a lock or free some memory that was
allocated. But this is error prone. Convert the code over to use the
guard() and free() helpers that let the compiler unlock locks or free
memory when the function exits.
- Remove disabling of interrupts in the function graph tracer
When function graph tracer was first introduced, it could race with
interrupts and NMIs. To prevent that race, it would disable
interrupts and not trace NMIs. But the code has changed to allow NMIs
and also interrupts. This change was done a long time ago, but the
disabling of interrupts was never removed. Remove the disabling of
interrupts in the function graph tracer is it is not needed. This
greatly improves its performance.
- Allow the :mod: command to enable tracing module functions on the
kernel command line.
The function tracer already has a way to enable functions to be
traced in modules by writing ":mod:<module>" into set_ftrace_filter.
That will enable either all the functions for the module if it is
loaded, or if it is not, it will cache that command, and when the
module is loaded that matches <module>, its functions will be
enabled. This also allows init functions to be traced. But currently
events do not have that feature.
Because enabling function tracing can be done very early at boot up
(before scheduling is enabled), the commands that can be done when
function tracing is started is limited. Having the ":mod:" command to
trace module functions as they are loaded is very useful. Update the
kernel command line function filtering to allow it.
* tag 'ftrace-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (26 commits)
ftrace: Implement :mod: cache filtering on kernel command line
tracing: Adopt __free() and guard() for trace_fprobe.c
bpf: Use ftrace_get_symaddr() for kprobe_multi probes
ftrace: Add ftrace_get_symaddr to convert fentry_ip to symaddr
Documentation: probes: Update fprobe on function-graph tracer
selftests/ftrace: Add a test case for repeating register/unregister fprobe
selftests: ftrace: Remove obsolate maxactive syntax check
tracing/fprobe: Remove nr_maxactive from fprobe
fprobe: Add fprobe_header encoding feature
fprobe: Rewrite fprobe on function-graph tracer
s390/tracing: Enable HAVE_FTRACE_GRAPH_FUNC
ftrace: Add CONFIG_HAVE_FTRACE_GRAPH_FUNC
bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled
tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS
tracing: Add ftrace_fill_perf_regs() for perf event
tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs
fprobe: Use ftrace_regs in fprobe exit handler
fprobe: Use ftrace_regs in fprobe entry handler
fgraph: Pass ftrace_regs to retfunc
fgraph: Replace fgraph_ret_regs with ftrace_regs
...
- Clean up the __rb_map_vma() logic
The logic of __rb_map_vma() has a error check with WARN_ON() that makes
sure that the index does not go past the end of the array of buffers. The
test in the loop pretty much guarantees that it will never happen, but
since the relation of the variables used is a little complex, the
WARN_ON() check was added. It was noticed that the array was dereferenced
before this check and if the logic does break and for some reason the
logic goes past the array, there will be an out of bounds access here.
Move the access to after the WARN_ON().
- Consolidate how the ring buffer is determined to be empty
Currently there's two ways that are used to determine if the ring buffer
is empty. One relies on the status of the commit and reader pages and what
was read, and the other is on what was written vs what was read. By using
the number of entries (written) method, it can be used for reading events
that are out of the kernel's control (what pKVM will use). Move to this
method to make it easier to implement a pKVM ring buffer that the kernel
can read.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ42XuRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qn3GAQCOQ94vr88FSXb/azC9281iDGYC/KbJ
7J4dGv2rXHpoVAEAtXRXSXpG0mTIJ6TtgVKgMrIFAuT/AVo4EIUr2q/CsgA=
=2G7c
-----END PGP SIGNATURE-----
Merge tag 'trace-ringbuffer-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull trace ring-buffer updates from Steven Rostedt:
- Clean up the __rb_map_vma() logic
The logic of __rb_map_vma() has a error check with WARN_ON() that
makes sure that the index does not go past the end of the array of
buffers. The test in the loop pretty much guarantees that it will
never happen, but since the relation of the variables used is a
little complex, the WARN_ON() check was added. It was noticed that
the array was dereferenced before this check and if the logic does
break and for some reason the logic goes past the array, there will
be an out of bounds access here. Move the access to after the
WARN_ON().
- Consolidate how the ring buffer is determined to be empty
Currently there's two ways that are used to determine if the ring
buffer is empty. One relies on the status of the commit and reader
pages and what was read, and the other is on what was written vs what
was read. By using the number of entries (written) method, it can be
used for reading events that are out of the kernel's control (what
pKVM will use). Move to this method to make it easier to implement a
pKVM ring buffer that the kernel can read.
* tag 'trace-ringbuffer-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Make reading page consistent with the code logic
ring-buffer: Check for empty ring-buffer with rb_num_of_entries()
The following works fine:
~# echo ':mod:trace_events_sample' > /sys/kernel/tracing/set_event
~# cat /sys/kernel/tracing/set_event
*:*:mod:trace_events_sample
~#
But if a name is given without a ':' where it can match an event name or
system name, the output of the cached events does not include a new line:
~# echo 'foo_bar:mod:trace_events_sample' > /sys/kernel/tracing/set_event
~# cat /sys/kernel/tracing/set_event
foo_bar:mod:trace_events_sample~#
Add the '\n' to that as well.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250121151336.6c491844@gandalf.local.home
Fixes: b355247df1 ("tracing: Cache ":mod:" events for modules not loaded yet")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The adding of cached events for modules not loaded yet required a
descriptor to separate the iteration of events with the iteration of
cached events for a module. But the allocation used the size of the
pointer and not the size of the contents to allocate its data and caused a
slab-out-of-bounds.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20250121151236.47fcf433@gandalf.local.home
Reported-by: Sasha Levin <sashal@kernel.org>
Closes: https://lore.kernel.org/all/Z4_OHKESRSiJcr-b@lappy/
Fixes: b355247df1 ("tracing: Cache ":mod:" events for modules not loaded yet")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Some architectures can not safely do atomic64 operations in NMI context.
Since the ring buffer relies on atomic64 operations to do its time
keeping, if an event is requested in NMI context, reject it for these
architectures.
Cc: stable@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andreas Larsson <andreas@gaisler.com>
Link: https://lore.kernel.org/20250120235721.407068250@goodmis.org
Fixes: c84897c0ff ("ring-buffer: Remove 32bit timestamp logic")
Closes: https://lore.kernel.org/all/86fb4f86-a0e4-45a2-a2df-3154acc4f086@gaisler.com/
Reported-by: Ludwig Rydberg <ludwig.rydberg@gaisler.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Seqlock optimizations that arose in a perf context and were
merged into the perf tree:
- seqlock: Add raw_seqcount_try_begin (Suren Baghdasaryan)
- mm: Convert mm_lock_seq to a proper seqcount ((Suren Baghdasaryan)
- mm: Introduce mmap_lock_speculate_{try_begin|retry} (Suren Baghdasaryan)
- mm/gup: Use raw_seqcount_try_begin() (Peter Zijlstra)
- Core perf enhancements:
- Reduce 'struct page' footprint of perf by mapping pages
in advance (Lorenzo Stoakes)
- Save raw sample data conditionally based on sample type (Yabin Cui)
- Reduce sampling overhead by checking sample_type in
perf_sample_save_callchain() and perf_sample_save_brstack() (Yabin Cui)
- Export perf_exclude_event() (Namhyung Kim)
- Uprobes scalability enhancements: (Andrii Nakryiko)
- Simplify find_active_uprobe_rcu() VMA checks
- Add speculative lockless VMA-to-inode-to-uprobe resolution
- Simplify session consumer tracking
- Decouple return_instance list traversal and freeing
- Ensure return_instance is detached from the list before freeing
- Reuse return_instances between multiple uretprobes within task
- Guard against kmemdup() failing in dup_return_instance()
- AMD core PMU driver enhancements:
- Relax privilege filter restriction on AMD IBS (Namhyung Kim)
- AMD RAPL energy counters support: (Dhananjay Ugwekar)
- Introduce topology_logical_core_id() (K Prateek Nayak)
- Remove the unused get_rapl_pmu_cpumask() function
- Remove the cpu_to_rapl_pmu() function
- Rename rapl_pmu variables
- Make rapl_model struct global
- Add arguments to the init and cleanup functions
- Modify the generic variable names to *_pkg*
- Remove the global variable rapl_msrs
- Move the cntr_mask to rapl_pmus struct
- Add core energy counter support for AMD CPUs
- Intel core PMU driver enhancements:
- Support RDPMC 'metrics clear mode' feature (Kan Liang)
- Clarify adaptive PEBS processing (Kan Liang)
- Factor out functions for PEBS records processing (Kan Liang)
- Simplify the PEBS records processing for adaptive PEBS (Kan Liang)
- Intel uncore driver enhancements: (Kan Liang)
- Convert buggy pmu->func_id use to pmu->registered
- Support more units on Granite Rapids
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=c8XB
-----END PGP SIGNATURE-----
Merge tag 'perf-core-2025-01-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull performance events updates from Ingo Molnar:
"Seqlock optimizations that arose in a perf context and were merged
into the perf tree:
- seqlock: Add raw_seqcount_try_begin (Suren Baghdasaryan)
- mm: Convert mm_lock_seq to a proper seqcount (Suren Baghdasaryan)
- mm: Introduce mmap_lock_speculate_{try_begin|retry} (Suren
Baghdasaryan)
- mm/gup: Use raw_seqcount_try_begin() (Peter Zijlstra)
Core perf enhancements:
- Reduce 'struct page' footprint of perf by mapping pages in advance
(Lorenzo Stoakes)
- Save raw sample data conditionally based on sample type (Yabin Cui)
- Reduce sampling overhead by checking sample_type in
perf_sample_save_callchain() and perf_sample_save_brstack() (Yabin
Cui)
- Export perf_exclude_event() (Namhyung Kim)
Uprobes scalability enhancements: (Andrii Nakryiko)
- Simplify find_active_uprobe_rcu() VMA checks
- Add speculative lockless VMA-to-inode-to-uprobe resolution
- Simplify session consumer tracking
- Decouple return_instance list traversal and freeing
- Ensure return_instance is detached from the list before freeing
- Reuse return_instances between multiple uretprobes within task
- Guard against kmemdup() failing in dup_return_instance()
AMD core PMU driver enhancements:
- Relax privilege filter restriction on AMD IBS (Namhyung Kim)
AMD RAPL energy counters support: (Dhananjay Ugwekar)
- Introduce topology_logical_core_id() (K Prateek Nayak)
- Remove the unused get_rapl_pmu_cpumask() function
- Remove the cpu_to_rapl_pmu() function
- Rename rapl_pmu variables
- Make rapl_model struct global
- Add arguments to the init and cleanup functions
- Modify the generic variable names to *_pkg*
- Remove the global variable rapl_msrs
- Move the cntr_mask to rapl_pmus struct
- Add core energy counter support for AMD CPUs
Intel core PMU driver enhancements:
- Support RDPMC 'metrics clear mode' feature (Kan Liang)
- Clarify adaptive PEBS processing (Kan Liang)
- Factor out functions for PEBS records processing (Kan Liang)
- Simplify the PEBS records processing for adaptive PEBS (Kan Liang)
Intel uncore driver enhancements: (Kan Liang)
- Convert buggy pmu->func_id use to pmu->registered
- Support more units on Granite Rapids"
* tag 'perf-core-2025-01-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
perf: map pages in advance
perf/x86/intel/uncore: Support more units on Granite Rapids
perf/x86/intel/uncore: Clean up func_id
perf/x86/intel: Support RDPMC metrics clear mode
uprobes: Guard against kmemdup() failing in dup_return_instance()
perf/x86: Relax privilege filter restriction on AMD IBS
perf/core: Export perf_exclude_event()
uprobes: Reuse return_instances between multiple uretprobes within task
uprobes: Ensure return_instance is detached from the list before freeing
uprobes: Decouple return_instance list traversal and freeing
uprobes: Simplify session consumer tracking
uprobes: add speculative lockless VMA-to-inode-to-uprobe resolution
uprobes: simplify find_active_uprobe_rcu() VMA checks
mm: introduce mmap_lock_speculate_{try_begin|retry}
mm: convert mm_lock_seq to a proper seqcount
mm/gup: Use raw_seqcount_try_begin()
seqlock: add raw_seqcount_try_begin
perf/x86/rapl: Add core energy counter support for AMD CPUs
perf/x86/rapl: Move the cntr_mask to rapl_pmus struct
perf/x86/rapl: Remove the global variable rapl_msrs
...
-----BEGIN PGP SIGNATURE-----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=EXYs
-----END PGP SIGNATURE-----
Merge tag 'for-6.14/block-20250118' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:
- NVMe pull requests via Keith:
- Target support for PCI-Endpoint transport (Damien)
- TCP IO queue spreading fixes (Sagi, Chaitanya)
- Target handling for "limited retry" flags (Guixen)
- Poll type fix (Yongsoo)
- Xarray storage error handling (Keisuke)
- Host memory buffer free size fix on error (Francis)
- MD pull requests via Song:
- Reintroduce md-linear (Yu Kuai)
- md-bitmap refactor and fix (Yu Kuai)
- Replace kmap_atomic with kmap_local_page (David Reaver)
- Quite a few queue freeze and debugfs deadlock fixes
Ming introduced lockdep support for this in the 6.13 kernel, and it
has (unsurprisingly) uncovered quite a few issues
- Use const attributes for IO schedulers
- Remove bio ioprio wrappers
- Fixes for stacked device atomic write support
- Refactor queue affinity helpers, in preparation for better supporting
isolated CPUs
- Cleanups of loop O_DIRECT handling
- Cleanup of BLK_MQ_F_* flags
- Add rotational support for null_blk
- Various fixes and cleanups
* tag 'for-6.14/block-20250118' of git://git.kernel.dk/linux: (106 commits)
block: Don't trim an atomic write
block: Add common atomic writes enable flag
md/md-linear: Fix a NULL vs IS_ERR() bug in linear_add()
block: limit disk max sectors to (LLONG_MAX >> 9)
block: Change blk_stack_atomic_writes_limits() unit_min check
block: Ensure start sector is aligned for stacking atomic writes
blk-mq: Move more error handling into blk_mq_submit_bio()
block: Reorder the request allocation code in blk_mq_submit_bio()
nvme: fix bogus kzalloc() return check in nvme_init_effects_log()
md/md-bitmap: move bitmap_{start, end}write to md upper layer
md/raid5: implement pers->bitmap_sector()
md: add a new callback pers->bitmap_sector()
md/md-bitmap: remove the last parameter for bimtap_ops->endwrite()
md/md-bitmap: factor behind write counters out from bitmap_{start/end}write()
md: Replace deprecated kmap_atomic() with kmap_local_page()
md: reintroduce md-linear
partitions: ldm: remove the initial kernel-doc notation
blk-cgroup: rwstat: fix kernel-doc warnings in header file
blk-cgroup: fix kernel-doc warnings in header file
nbd: fix partial sending
...
The static function in trace_events.c called update_cache() is too generic
and conflicts with the function defined in arch/openrisc/include/asm/pgtable.h
Rename it to update_mod_cache() to make it less generic.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250120172756.4ecfb43f@batman.local.home
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202501210550.Ufrj5CRn-lkp@intel.com/
Fixes: b355247df1 ("tracing: Cache ":mod:" events for modules not loaded yet")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZ4pR0wAKCRCRxhvAZXjc
ojb2AQD5QfpTEX/ju1TkenTvoNl+JfnIjaVSY40Lm9DWYzmCMAEAuRvf5WRIV713
00/RVOrUvsLobzhmnk0yw53EQ5A+pA0=
=2NDA
-----END PGP SIGNATURE-----
Merge tag 'kernel-6.14-rc1.pid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull pid_max namespacing update from Christian Brauner:
"The pid_max sysctl is a global value. For a long time the default
value has been 65535 and during the pidfd dicussions Linus proposed to
bump pid_max by default. Based on this discussion systemd started
bumping pid_max to 2^22. So all new systems now run with a very high
pid_max limit with some distros having also backported that change.
The decision to bump pid_max is obviously correct. It just doesn't
make a lot of sense nowadays to enforce such a low pid number. There's
sufficient tooling to make selecting specific processes without typing
really large pid numbers available.
In any case, there are workloads that have expections about how large
pid numbers they accept. Either for historical reasons or
architectural reasons. One concreate example is the 32-bit version of
Android's bionic libc which requires pid numbers less than 65536.
There are workloads where it is run in a 32-bit container on a 64-bit
kernel. If the host has a pid_max value greater than 65535 the libc
will abort thread creation because of size assumptions of
pthread_mutex_t.
That's a fairly specific use-case however, in general specific
workloads that are moved into containers running on a host with a new
kernel and a new systemd can run into issues with large pid_max
values. Obviously making assumptions about the size of the allocated
pid is suboptimal but we have userspace that does it.
Of course, giving containers the ability to restrict the number of
processes in their respective pid namespace indepent of the global
limit through pid_max is something desirable in itself and comes in
handy in general.
Independent of motivating use-cases the existence of pid namespaces
makes this also a good semantical extension and there have been prior
proposals pushing in a similar direction. The trick here is to
minimize the risk of regressions which I think is doable. The fact
that pid namespaces are hierarchical will help us here.
What we mostly care about is that when the host sets a low pid_max
limit, say (crazy number) 100 that no descendant pid namespace can
allocate a higher pid number in its namespace. Since pid allocation is
hierarchial this can be ensured by checking each pid allocation
against the pid namespace's pid_max limit. This means if the
allocation in the descendant pid namespace succeeds, the ancestor pid
namespace can reject it. If the ancestor pid namespace has a higher
limit than the descendant pid namespace the descendant pid namespace
will reject the pid allocation. The ancestor pid namespace will
obviously not care about this.
All in all this means pid_max continues to enforce a system wide limit
on the number of processes but allows pid namespaces sufficient leeway
in handling workloads with assumptions about pid values and allows
containers to restrict the number of processes in a pid namespace
through the pid_max interface"
* tag 'kernel-6.14-rc1.pid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
tests/pid_namespace: add pid_max tests
pid: allow pid_max to be set per pid namespace
A typo was introduced when adding the ":mod:" command that did
a "#if CONFIG_MODULES" instead of a "#ifdef CONFIG_MODULES".
Fix it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20250120125745.4ac90ca6@gandalf.local.home
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202501190121.E2CIJuUj-lkp@intel.com/
Fixes: b355247df1 ("tracing: Cache ":mod:" events for modules not loaded yet")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Module functions can be set to set_ftrace_filter before the module is
loaded.
# echo :mod:snd_hda_intel > set_ftrace_filter
This will enable all the functions for the module snd_hda_intel. If that
module is not loaded, it is "cached" in the trace array for when the
module is loaded, its functions will be traced.
But this is not implemented in the kernel command line. That's because the
kernel command line filtering is added very early in boot up as it is
needed to be done before boot time function tracing can start, which is
also available very early in boot up. The code used by the
"set_ftrace_filter" file can not be used that early as it depends on some
other initialization to occur first. But some of the functions can.
Implement the ":mod:" feature of "set_ftrace_filter" in the kernel command
line parsing. Now function tracing on just a single module that is loaded
at boot up can be done.
Adding:
ftrace=function ftrace_filter=:mod:sna_hda_intel
To the kernel command line will only enable the sna_hda_intel module
functions when the module is loaded, and it will start tracing.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250116175832.34e39779@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the :mod: command is written into /sys/kernel/tracing/set_event (or
that file within an instance), if the module specified after the ":mod:"
is not yet loaded, it will store that string internally. When the module
is loaded, it will enable the events as if the module was loaded when the
string was written into the set_event file.
This can also be useful to enable events that are in the init section of
the module, as the events are enabled before the init section is executed.
This also works on the kernel command line:
trace_event=:mod:<module>
Will enable the events for <module> when it is loaded.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250116143533.514730995@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a :mod: command to enable only events from a given module from the
set_events file.
echo '*:mod:<module>' > set_events
Or
echo ':mod:<module>' > set_events
Will enable all events for that module. Specific events can also be
enabled via:
echo '<event>:mod:<module>' > set_events
Or
echo '<system>:<event>:mod:<module>' > set_events
Or
echo '*:<event>:mod:<module>' > set_events
The ":mod:" keyword is consistent with the function tracing filter to
enable functions from a given module.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250116143533.214496360@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function graph tracer has become generic so that kretprobes and BPF
can use it along with function graph tracing itself. Some of the
infrastructure was specific for function graph tracing such as recording
the calltime and return time of the functions. Calling the clock code on a
high volume function does add overhead. The calculation of the calltime
was removed from the generic code and placed into the function graph
tracer itself so that the other users did not incur this overhead as they
did not need that timestamp.
The calltime field was still kept in the generic return entry structure
and the function graph return entry callback filled it as that structure
was passed to other code.
But this broke both irqsoff and wakeup latency tracer as they still
depended on the trace structure containing the calltime when the option
display-graph is set as it used some of those same functions that the
function graph tracer used. But now the calltime was not set and was just
zero. This caused the calculation of the function time to be the absolute
value of the return timestamp and not the length of the function.
# cd /sys/kernel/tracing
# echo 1 > options/display-graph
# echo irqsoff > current_tracer
The tracers went from:
# REL TIME CPU TASK/PID |||| DURATION FUNCTION CALLS
# | | | | |||| | | | | | |
0 us | 4) <idle>-0 | d..1. | 0.000 us | irqentry_enter();
3 us | 4) <idle>-0 | d..2. | | irq_enter_rcu() {
4 us | 4) <idle>-0 | d..2. | 0.431 us | preempt_count_add();
5 us | 4) <idle>-0 | d.h2. | | tick_irq_enter() {
5 us | 4) <idle>-0 | d.h2. | 0.433 us | tick_check_oneshot_broadcast_this_cpu();
6 us | 4) <idle>-0 | d.h2. | 2.426 us | ktime_get();
9 us | 4) <idle>-0 | d.h2. | | tick_nohz_stop_idle() {
10 us | 4) <idle>-0 | d.h2. | 0.398 us | nr_iowait_cpu();
11 us | 4) <idle>-0 | d.h1. | 1.903 us | }
11 us | 4) <idle>-0 | d.h2. | | tick_do_update_jiffies64() {
12 us | 4) <idle>-0 | d.h2. | | _raw_spin_lock() {
12 us | 4) <idle>-0 | d.h2. | 0.360 us | preempt_count_add();
13 us | 4) <idle>-0 | d.h3. | 0.354 us | do_raw_spin_lock();
14 us | 4) <idle>-0 | d.h2. | 2.207 us | }
15 us | 4) <idle>-0 | d.h3. | 0.428 us | calc_global_load();
16 us | 4) <idle>-0 | d.h3. | | _raw_spin_unlock() {
16 us | 4) <idle>-0 | d.h3. | 0.380 us | do_raw_spin_unlock();
17 us | 4) <idle>-0 | d.h3. | 0.334 us | preempt_count_sub();
18 us | 4) <idle>-0 | d.h1. | 1.768 us | }
18 us | 4) <idle>-0 | d.h2. | | update_wall_time() {
[..]
To:
# REL TIME CPU TASK/PID |||| DURATION FUNCTION CALLS
# | | | | |||| | | | | | |
0 us | 5) <idle>-0 | d.s2. | 0.000 us | _raw_spin_lock_irqsave();
0 us | 5) <idle>-0 | d.s3. | 312159583 us | preempt_count_add();
2 us | 5) <idle>-0 | d.s4. | 312159585 us | do_raw_spin_lock();
3 us | 5) <idle>-0 | d.s4. | | _raw_spin_unlock() {
3 us | 5) <idle>-0 | d.s4. | 312159586 us | do_raw_spin_unlock();
4 us | 5) <idle>-0 | d.s4. | 312159587 us | preempt_count_sub();
4 us | 5) <idle>-0 | d.s2. | 312159587 us | }
5 us | 5) <idle>-0 | d.s3. | | _raw_spin_lock() {
5 us | 5) <idle>-0 | d.s3. | 312159588 us | preempt_count_add();
6 us | 5) <idle>-0 | d.s4. | 312159589 us | do_raw_spin_lock();
7 us | 5) <idle>-0 | d.s3. | 312159590 us | }
8 us | 5) <idle>-0 | d.s4. | 312159591 us | calc_wheel_index();
9 us | 5) <idle>-0 | d.s4. | | enqueue_timer() {
9 us | 5) <idle>-0 | d.s4. | | wake_up_nohz_cpu() {
11 us | 5) <idle>-0 | d.s4. | | native_smp_send_reschedule() {
11 us | 5) <idle>-0 | d.s4. | 312171987 us | default_send_IPI_single_phys();
12408 us | 5) <idle>-0 | d.s3. | 312171990 us | }
12408 us | 5) <idle>-0 | d.s3. | 312171991 us | }
12409 us | 5) <idle>-0 | d.s3. | 312171991 us | }
Where the calculation of the time for each function was the return time
minus zero and not the time of when the function returned.
Have these tracers also save the calltime in the fgraph data section and
retrieve it again on the return to get the correct timings again.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/20250113183124.61767419@gandalf.local.home
Fixes: f1f36e22be ("ftrace: Have calltime be saved in the fgraph storage")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In the loop of __rb_map_vma(), the 's' variable is calculated from the
same logic that nr_pages is and they both come from nr_subbufs. But the
relationship is not obvious and there's a WARN_ON_ONCE() around the 's'
variable to make sure it never becomes equal to nr_subbufs within the
loop. If that happens, then the code is buggy and needs to be fixed.
The 'page' variable is calculated from cpu_buffer->subbuf_ids[s] which is
an array of 'nr_subbufs' entries. If the code becomes buggy and 's'
becomes equal to or greater than 'nr_subbufs' then this will be an out of
bounds hit before the WARN_ON() is triggered and the code exiting safely.
Make the 'page' initialization consistent with the code logic and assign
it after the out of bounds check.
Link: https://lore.kernel.org/20250110162612.13983-1-aha310510@gmail.com
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
[ sdr: rewrote change log ]
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently there are two ways of identifying an empty ring-buffer. One
relying on the current status of the commit / reader page
(rb_per_cpu_empty()) and the other on the write and read counters
(rb_num_of_entries() used in rb_get_reader_page()).
with rb_num_of_entries(). This intends to ease later
introduction of ring-buffer writers which are out of the kernel control
and with whom, the only information available is through the meta-page
counters.
Link: https://lore.kernel.org/20250108114536.627715-2-vdonnefort@google.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add ftrace_get_entry_ip() which is only for ftrace based probes, and use
it for kprobe multi probes because they are based on fprobe which uses
ftrace instead of kprobes.
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/173566081414.878879.10631096557346094362.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In __trace_kprobe_create(), if something fails it must goto error block
to free objects. But when strdup() a symbol, it returns without that.
Fix it to goto the error block to free objects correctly.
Link: https://lore.kernel.org/all/173643297743.1514810.2408159540454241947.stgit@devnote2/
Fixes: 6212dd2968 ("tracing/kprobes: Use dyn_event framework for kprobe events")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When kprobe multi bpf program can't be executed due to recursion check,
we currently return 0 (success) to fprobe layer where it's ignored for
standard kprobe multi probes.
For kprobe session the success return value will make fprobe layer to
install return probe and try to execute it as well.
But the return session probe should not get executed, because the entry
part did not run. FWIW the return probe bpf program most likely won't get
executed, because its recursion check will likely fail as well, but we
don't need to run it in the first place.. also we can make this clear
and obvious.
It also affects missed counts for kprobe session program execution, which
are now doubled (extra count for not executed return probe).
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20250106175048.1443905-1-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit ef1b808e3b ("bpf: Fix UAF via mismatching bpf_prog/attachment
RCU flavors") resolved a possible UAF issue in uprobes that attach
non-sleepable bpf prog by explicitly waiting for a tasks-trace-RCU grace
period. But, in the current implementation, synchronize_rcu_tasks_trace
is included within the mutex critical section, which increases the
length of the critical section and may affect performance. So let's move
out synchronize_rcu_tasks_trace from mutex CS.
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20250104013946.1111785-1-pulehui@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Since POLLIN will not be flushed until the hist file is read, the user
needs to repeatedly read() and poll() on the hist file for monitoring the
event continuously. But the read() is somewhat redundant when the user is
only monitoring for event updates.
Add POLLPRI poll event on the hist file so the event returns when a
histogram is updated after open(), poll() or read(). Thus it is possible
to wait for the next event without having to issue a read().
Cc: Shuah Khan <shuah@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/173527248770.464571.2536902137325258133.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add poll syscall support on the `hist` file. The Waiter will be waken
up when the histogram is updated with POLLIN.
Currently, there is no way to wait for a specific event in userspace.
So user needs to peek the `trace` periodicaly, or wait on `trace_pipe`.
But it is not a good idea to peek at the `trace` for an event that
randomly happens. And `trace_pipe` is not coming back until a page is
filled with events.
This allows a user to wait for a specific event on the `hist` file. User
can set a histogram trigger on the event which they want to monitor
and poll() on its `hist` file. Since this poll() returns POLLIN, the next
poll() will return soon unless a read() happens on that hist file.
NOTE: To read the hist file again, you must set the file offset to 0,
but just for monitoring the event, you may not need to read the
histogram.
Cc: Shuah Khan <shuah@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/173527247756.464571.14236296701625509931.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the function tracing_set_tracer() switched over to using the guard()
infrastructure, it did not need to save the 'ret' variable and would just
return the value when an error arised, instead of setting ret and jumping
to an out label.
When CONFIG_TRACER_SNAPSHOT is enabled, it had code that expected the
"ret" variable to be initialized to zero and had set 'ret' while holding
an arch_spin_lock() (not used by guard), and then upon releasing the lock
it would check 'ret' and exit if set. But because ret was only set when an
error occurred while holding the locks, 'ret' would be used uninitialized
if there was no error. The code in the CONFIG_TRACER_SNAPSHOT block should
be self contain. Make sure 'ret' is also set when no error occurred.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250106111143.2f90ff65@gandalf.local.home
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202412271654.nJVBuwmF-lkp@intel.com/
Fixes: d33b10c0c7 ("tracing: Switch trace.c code over to use guard()")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
- Add needed READ_ONCE() around access to the fgraph array element
The updates to the fgraph array can happen when callbacks are registered
and unregistered. The __ftrace_return_to_handler() can handle reading
either the old value or the new value. But once it reads that value
it must stay consistent otherwise the check that looks to see if the
value is a stub may show false, but if the compiler decides to re-read
after that check, it can be true which can cause the code to crash
later on.
- Make function profiler use the top level ops for filtering again
When function graph became available for instances, its filter ops became
independent from the top level set_ftrace_filter. In the process the
function profiler received its own filter ops as well. But the function
profiler uses the top level set_ftrace_filter file and does not have one
of its own. In giving it its own filter ops, it lost any user interface
it once had. Make it use the top level set_ftrace_filter file again.
This fixes a regression.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ3cR4RQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qjxfAQCPhNztdmGmEYmuBtONPHwejidWnuJ6
Rl2mQxEbp40OUgD+JvSWofhRsvtXWlymqZ9j+dKMegLqMeq834hB0LK4NAg=
=+KqV
-----END PGP SIGNATURE-----
Merge tag 'ftrace-v6.13-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace fixes from Steven Rostedt:
- Add needed READ_ONCE() around access to the fgraph array element
The updates to the fgraph array can happen when callbacks are
registered and unregistered. The __ftrace_return_to_handler() can
handle reading either the old value or the new value. But once it
reads that value it must stay consistent otherwise the check that
looks to see if the value is a stub may show false, but if the
compiler decides to re-read after that check, it can be true which
can cause the code to crash later on.
- Make function profiler use the top level ops for filtering again
When function graph became available for instances, its filter ops
became independent from the top level set_ftrace_filter. In the
process the function profiler received its own filter ops as well.
But the function profiler uses the top level set_ftrace_filter file
and does not have one of its own. In giving it its own filter ops, it
lost any user interface it once had. Make it use the top level
set_ftrace_filter file again. This fixes a regression.
* tag 'ftrace-v6.13-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ftrace: Fix function profiler's filtering functionality
fgraph: Add READ_ONCE() when accessing fgraph_array[]
Commit c132be2c4f ("function_graph: Have the instances use their own
ftrace_ops for filtering"), function profiler (enabled via
function_profile_enabled) has been showing statistics for all functions,
ignoring set_ftrace_filter settings.
While tracers are instantiated, the function profiler is not. Therefore, it
should use the global set_ftrace_filter for consistency. This patch
modifies the function profiler to use the global filter, fixing the
filtering functionality.
Before (filtering not working):
```
root@localhost:~# echo 'vfs*' > /sys/kernel/tracing/set_ftrace_filter
root@localhost:~# echo 1 > /sys/kernel/tracing/function_profile_enabled
root@localhost:~# sleep 1
root@localhost:~# echo 0 > /sys/kernel/tracing/function_profile_enabled
root@localhost:~# head /sys/kernel/tracing/trace_stat/*
Function Hit Time Avg
s^2
-------- --- ---- ---
---
schedule 314 22290594 us 70989.15 us
40372231 us
x64_sys_call 1527 8762510 us 5738.382 us
3414354 us
schedule_hrtimeout_range 176 8665356 us 49234.98 us
405618876 us
__x64_sys_ppoll 324 5656635 us 17458.75 us
19203976 us
do_sys_poll 324 5653747 us 17449.83 us
19214945 us
schedule_timeout 67 5531396 us 82558.15 us
2136740827 us
__x64_sys_pselect6 12 3029540 us 252461.7 us
63296940171 us
do_pselect.constprop.0 12 3029532 us 252461.0 us
63296952931 us
```
After (filtering working):
```
root@localhost:~# echo 'vfs*' > /sys/kernel/tracing/set_ftrace_filter
root@localhost:~# echo 1 > /sys/kernel/tracing/function_profile_enabled
root@localhost:~# sleep 1
root@localhost:~# echo 0 > /sys/kernel/tracing/function_profile_enabled
root@localhost:~# head /sys/kernel/tracing/trace_stat/*
Function Hit Time Avg
s^2
-------- --- ---- ---
---
vfs_write 462 68476.43 us 148.217 us
25874.48 us
vfs_read 641 9611.356 us 14.994 us
28868.07 us
vfs_fstat 890 878.094 us 0.986 us
1.667 us
vfs_fstatat 227 757.176 us 3.335 us
18.928 us
vfs_statx 226 610.610 us 2.701 us
17.749 us
vfs_getattr_nosec 1187 460.919 us 0.388 us
0.326 us
vfs_statx_path 297 343.287 us 1.155 us
11.116 us
vfs_rename 6 291.575 us 48.595 us
9889.236 us
```
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20250101190820.72534-1-enjuk@amazon.com
Fixes: c132be2c4f ("function_graph: Have the instances use their own ftrace_ops for filtering")
Signed-off-by: Kohei Enju <enjuk@amazon.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In __ftrace_return_to_handler(), a loop iterates over the fgraph_array[]
elements, which are fgraph_ops. The loop checks if an element is a
fgraph_stub to prevent using a fgraph_stub afterward.
However, if the compiler reloads fgraph_array[] after this check, it might
race with an update to fgraph_array[] that introduces a fgraph_stub. This
could result in the stub being processed, but the stub contains a null
"func_hash" field, leading to a NULL pointer dereference.
To ensure that the gops compared against the fgraph_stub matches the gops
processed later, add a READ_ONCE(). A similar patch appears in commit
63a8dfb ("function_graph: Add READ_ONCE() when accessing fgraph_array[]").
Cc: stable@vger.kernel.org
Fixes: 37238abe3c ("ftrace/function_graph: Pass fgraph_ops to function graph callbacks")
Link: https://lore.kernel.org/20241231113731.277668-1-zilin@seu.edu.cn
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In order to catch a common bug where a TRACE_EVENT() TP_fast_assign()
assigns an address of an allocated string to the ring buffer and then
references it in TP_printk(), which can be executed hours later when the
string is free, the function test_event_printk() runs on all events as
they are registered to make sure there's no unwanted dereferencing.
It calls process_string() to handle cases in TP_printk() format that has
"%s". It returns whether or not the string is safe. But it can have some
false positives.
For instance, xe_bo_move() has:
TP_printk("move_lacks_source:%s, migrate object %p [size %zu] from %s to %s device_id:%s",
__entry->move_lacks_source ? "yes" : "no", __entry->bo, __entry->size,
xe_mem_type_to_name[__entry->old_placement],
xe_mem_type_to_name[__entry->new_placement], __get_str(device_id))
Where the "%s" references into xe_mem_type_to_name[]. This is an array of
pointers that should be safe for the event to access. Instead of flagging
this as a bad reference, if a reference points to an array, where the
record field is the index, consider it safe.
Link: https://lore.kernel.org/all/9dee19b6185d325d0e6fa5f7cbba81d007d99166.camel@sapience.com/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241231000646.324fb5f7@gandalf.local.home
Fixes: 65a25d9f7a ("tracing: Add "%s" check in test_event_printk()")
Reported-by: Genes Lists <lists@sapience.com>
Tested-by: Gene C <arch@sapience.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
dot2k suggests a list of changes to the kernel tree while adding a
monitor: edit tracepoints header, Makefile, Kconfig and moving the
monitor folder. Those changes can be easily run automatically.
Add a flag to dot2k to alter the kernel source.
The kernel source directory can be either assumed from the PWD, or from
the running kernel, if installed.
This feature works best if the kernel tree is a git repository, so that
its easier to make sure there are no unintended changes.
The main RV files (e.g. Makefile) have now a comment placeholder that
can be useful for manual editing (e.g. to know where to add new
monitors) and it is used by the script to append the required lines.
We also slightly adapt the file handling functions in dot2k: __open_file
is now called __read_file and also closes the file before returning the
content; __create_file is now a more general __write_file, we no longer
return on FileExistsError (not thrown while opening), a new
__create_file simply calls __write_file specifying the monitor folder in
the path.
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20241227144752.362911-8-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
While creating a new monitor in RV, besides generating code from dot2k,
there are a few manual steps which can be tedious and error prone, like
adding the tracepoints, makefile lines and kconfig.
This patch restructures the existing monitors to keep some files in the
monitor's folder itself, which can be automatically generated by future
versions of dot2k.
Monitors have now their own Kconfig and tracepoint snippets. For
simplicity, the main tracepoint definition, is moved to the RV
directory, it defines only the tracepoint classes and includes the
monitor-specific tracepoints, which reside in the monitor directory.
Tracepoints and Kconfig no longer need to be copied and adapted from
existing ones but only need to be included in the main files.
The Makefile remains untouched since there's little advantage in having
a separated Makefile for each monitor with a single line and including
it in the main RV Makefile.
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20241227144752.362911-6-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- tracing/kprobes: Change the priority of the module callback of kprobe
events so that it is called after the jump label list on the module is
updated. This ensures the kprobe can check whether it is not on the
jump label address correctly.
-----BEGIN PGP SIGNATURE-----
iQFPBAABCgA5FiEEh7BulGwFlgAOi5DV2/sHvwUrPxsFAmduAMgbHG1hc2FtaS5o
aXJhbWF0c3VAZ21haWwuY29tAAoJENv7B78FKz8bJ6YH/2QBkWNTe3qjxdPsTxJ2
MyL2PO8tMwZbNSyYZ1yGnbguWUUKVkuiheS/qWhLNpuVEyb6Q9/Zuifh5rFqDbf0
Ug3YvsP7gQurmqDm1NGlnMic3zlmZaYDtXCKB+kiA3HO3iP92zesTJlasiok3aSd
sQphxUzmG41BQUDN5/LktGjVb5juf3Xq6i6bdCd6wunUbGWCEE+XmFrg1oVnutES
GTckUGswUBGbgkcVPc07UfKZpNzZdyZlmbVfOISCdYIAddUKftATN7SaUrM29oqC
/lkUcxeXSVXBIUkbA1p50nfjYzTWNeXG92WrvMrRZjNivyMf/nUJnxrlHsv5h2Dy
gtI=
=d3Zj
-----END PGP SIGNATURE-----
Merge tag 'probes-fixes-v6.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes fix from Masami Hiramatsu:
"Change the priority of the module callback of kprobe events so that it
is called after the jump label list on the module is updated.
This ensures the kprobe can check whether it is not on the jump label
address correctly"
* tag 'probes-fixes-v6.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/kprobe: Make trace_kprobe's module callback called after jump_label update
Fprobe store its data structure address and size on the fgraph return stack
by __fprobe_header. But most 64bit architecture can combine those to
one unsigned long value because 4 MSB in the kernel address are the same.
With this encoding, fprobe can consume less space on ret_stack.
This introduces asm/fprobe.h to define arch dependent encode/decode
macros. Note that since fprobe depends on CONFIG_HAVE_FUNCTION_GRAPH_FREGS,
currently only arm64, loongarch, riscv, s390 and x86 are supported.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/173519005783.391279.5307910947400277525.stgit@devnote2
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Rewrite fprobe implementation on function-graph tracer.
Major API changes are:
- 'nr_maxactive' field is deprecated.
- This depends on CONFIG_DYNAMIC_FTRACE_WITH_ARGS or
!CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS, and
CONFIG_HAVE_FUNCTION_GRAPH_FREGS. So currently works only
on x86_64.
- Currently the entry size is limited in 15 * sizeof(long).
- If there is too many fprobe exit handler set on the same
function, it will fail to probe.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/173519003970.391279.14406792285453830996.stgit@devnote2
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add CONFIG_HAVE_FTRACE_GRAPH_FUNC kconfig in addition to ftrace_graph_func
macro check. This is for the other feature (e.g. FPROBE) which requires to
access ftrace_regs from fgraph_ops::entryfunc() can avoid compiling if
the fgraph can not pass the valid ftrace_regs.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/173519001472.391279.1174901685282588467.stgit@devnote2
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Enable kprobe_multi feature if CONFIG_FPROBE is enabled. The pt_regs is
converted from ftrace_regs by ftrace_partial_regs(), thus some registers
may always returns 0. But it should be enough for function entry (access
arguments) and exit (access return value).
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/173519000417.391279.14011193569589886419.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Florent Revest <revest@chromium.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Allow fprobe events to be enabled with CONFIG_DYNAMIC_FTRACE_WITH_ARGS.
With this change, fprobe events mostly use ftrace_regs instead of pt_regs.
Note that if the arch doesn't enable HAVE_FTRACE_REGS_HAVING_PT_REGS,
fprobe events will not be able to be used from perf.
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/173518999352.391279.13332699755290175168.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Change the fprobe exit handler to use ftrace_regs structure instead of
pt_regs. This also introduce HAVE_FTRACE_REGS_HAVING_PT_REGS which
means the ftrace_regs is including the pt_regs so that ftrace_regs
can provide pt_regs without memory allocation.
Fprobe introduces a new dependency with that.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Song Liu <song@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Matt Bobrowski <mattbobrowski@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Hao Luo <haoluo@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/173518995092.391279.6765116450352977627.stgit@devnote2
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This allows fprobes to be available with CONFIG_DYNAMIC_FTRACE_WITH_ARGS
instead of CONFIG_DYNAMIC_FTRACE_WITH_REGS, then we can enable fprobe
on arm64.
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/173518994037.391279.2786805566359674586.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Florent Revest <revest@chromium.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pass ftrace_regs to the fgraph_ops::retfunc(). If ftrace_regs is not
available, it passes a NULL instead. User callback function can access
some registers (including return address) via this ftrace_regs.
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/173518992972.391279.14055405490327765506.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pass ftrace_regs to the fgraph_ops::entryfunc(). If ftrace_regs is not
available, it passes a NULL instead. User callback function can access
some registers (including return address) via this ftrace_regs.
Note that the ftrace_regs can be NULL when the arch does NOT define:
HAVE_DYNAMIC_FTRACE_WITH_ARGS or HAVE_DYNAMIC_FTRACE_WITH_REGS.
More specifically, if HAVE_DYNAMIC_FTRACE_WITH_REGS is defined but
not the HAVE_DYNAMIC_FTRACE_WITH_ARGS, and the ftrace ops used to
register the function callback does not set FTRACE_OPS_FL_SAVE_REGS.
In this case, ftrace_regs can be NULL in user callback.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/173518990044.391279.17406984900626078579.stgit@devnote2
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function dyn_event_release() uses argv_split() which must be freed via
argv_free(). It contains several error paths that do a goto out to call
argv_free() for cleanup. This makes the code complex and error prone.
Create a new __free() directive __free(argv_free) that will call
argv_free() for data allocated with argv_split(), and use it in the
dyn_event_release() function.
Cc: Kees Cook <kees@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Shevchenko <andy@kernel.org>
Cc: linux-hardening@vger.kernel.org
Link: https://lore.kernel.org/20241220103313.4a74ec8e@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are a couple functions in trace_stat.c that have "goto out" or
equivalent on error in order to release locks that were taken. This can be
error prone or just simply make the code more complex.
Switch every location that ends with unlocking a mutex on error over to
using the guard(mutex)() infrastructure to let the compiler worry about
releasing locks. This makes the code easier to read and understand.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241219201346.870318466@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function stack_trace_sysctl() uses a goto on the error path to jump to
the mutex_unlock() code. Replace the logic to use guard() and let the
compiler worry about it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241225222931.684913592@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The osnoise_hotplug_workfn() grabs two mutexes and cpu_read_lock(). It has
various gotos to handle unlocking them. Switch them over to guard() and
let the compiler worry about it.
The osnoise_cpus_read() has a temporary mask_str allocated and there's
some gotos to make sure it gets freed on error paths. Switch that over to
__free() to let the compiler worry about it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241225222931.517329690@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are a couple functions in trace_events_synth.c that have "goto out"
or equivalent on error in order to release locks that were taken. This can
be error prone or just simply make the code more complex.
Switch every location that ends with unlocking a mutex on error over to
using the guard(mutex)() infrastructure to let the compiler worry about
releasing locks. This makes the code easier to read and understand.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241219201346.371082515@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are a couple functions in trace_events_filter.c that have "goto out"
or equivalent on error in order to release locks that were taken. This can
be error prone or just simply make the code more complex.
Switch every location that ends with unlocking a mutex on error over to
using the guard(mutex)() infrastructure to let the compiler worry about
releasing locks. This makes the code easier to read and understand.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241219201346.200737679@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are a few functions in trace_events_trigger.c that have "goto out" or
equivalent on error in order to release locks that were taken. This can be
error prone or just simply make the code more complex.
Switch every location that ends with unlocking a mutex on error over to
using the guard(mutex)() infrastructure to let the compiler worry about
releasing locks. This makes the code easier to read and understand.
Also use __free() for free a temporary buffer in event_trigger_regex_write().
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241220110621.639d3bc8@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are a couple functions in trace_events_hist.c that have "goto out" or
equivalent on error in order to release locks that were taken. This can be
error prone or just simply make the code more complex.
Switch every location that ends with unlocking a mutex on error over to
using the guard(mutex)() infrastructure to let the compiler worry about
releasing locks. This makes the code easier to read and understand.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241219201345.694601480@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are several functions in trace_events.c that have "goto out;" or
equivalent on error in order to release locks that were taken. This can be
error prone or just simply make the code more complex.
Switch every location that ends with unlocking a mutex on error over to
using the guard(mutex)() infrastructure to let the compiler worry about
releasing locks. This makes the code easier to read and understand.
Some locations did some simple arithmetic after releasing the lock. As
this causes no real overhead for holding a mutex while processing the file
position (*ppos += cnt;) let the lock be held over this logic too.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241219201345.522546095@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently there's an "out_reg:" label that gets jumped to if there's no
parameters to process. Instead, make it a proper "if (param) { }" block as
there's not much to do for the parameter processing, and remove the
"out_reg:" label.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241219201345.354746196@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The event_enable_func() function allocates the data descriptor early in
the function just to assign its data->count value via:
kstrtoul(number, 0, &data->count);
This makes the code more complex as there are several error paths before
the data descriptor is actually used. This means there needs to be a
goto out_free; to clean it up.
Use a local variable "count" to do the update and move the data allocation
just before it is used. This removes the "out_free" label as the data can
be freed on the failure path of where it is used.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241219201345.190820140@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The event_enable_write() function is inconsistent in how it returns
errors. Sometimes it updates the ppos parameter and sometimes it doesn't.
Simplify the code to just return an error or the count if there isn't an
error.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241219201345.025284170@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The mmiotracer is not set to be enabled at boot up from the kernel command
line. If the boot command line tries to enable that tracer, it will fail
to be enabled. The return code is currently zero when that happens so the
caller just thinks it was enabled. Return -EINVAL in this case.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241219201344.854254394@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are several functions in trace.c that have "goto out;" or
equivalent on error in order to release locks or free values that were
allocated. This can be error prone or just simply make the code more
complex.
Switch every location that ends with unlocking a mutex or freeing on error
over to using the guard(mutex)() and __free() infrastructure to let the
compiler worry about releasing locks. This makes the code easier to read
and understand.
There's one place that should probably return an error but instead return
0. This does not change the return as the only changes are to do the
conversion without changing the logic. Fixing that location will have to
come later.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://lore.kernel.org/20241224221413.7b8c68c3@batman.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Get the ftrace recursion lock in the generic function_graph_enter()
instead of each architecture code.
This changes all function_graph tracer callbacks running in
non-preemptive state. On x86 and powerpc, this is by default, but
on the other architecutres, this will be new.
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/173379653720.973433.18438622234884980494.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are a few functions in ftrace.c that have "goto out" or equivalent
on error in order to release locks that were taken. This can be error
prone or just simply make the code more complex.
Switch every location that ends with unlocking a mutex on error over to
using the guard(mutex)() infrastructure to let the compiler worry about
releasing locks. This makes the code easier to read and understand.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20241223184941.718001540@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are some goto jumps to exit a program to just return a value. The
code after the label doesn't free anything nor does it do any unlocks. It
simply returns the variable that was set before the jump.
Remove these unneeded goto jumps.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20241223184941.544855549@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
A recent change added return 0 before an existing return statement
at the end of function blk_trace_setup. The final return is now
redundant, so remove it.
Fixes: 64d124798244 ("blktrace: move copy_[to|from]_user() out of ->debugfs_lock")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20241204150450.399005-1-colin.i.king@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Call each handler directly and the handler do grab q->debugfs_mutex,
prepare for killing dependency between ->debug_mutex and ->mmap_lock.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241128125029.4152292-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Make sure the trace_kprobe's module notifer callback function is called
after jump_label's callback is called. Since the trace_kprobe's callback
eventually checks jump_label address during registering new kprobe on
the loading module, jump_label must be updated before this registration
happens.
Link: https://lore.kernel.org/all/173387585556.995044.3157941002975446119.stgit@devnote2/
Fixes: 6142431810 ("tracing/kprobes: Support module init function probing")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
- Fix possible overflow of mmapped ring buffer with bad offset
If the mmap() to the ring buffer passes in a start address that
is passed the end of the mmapped file, it is not caught and
a slab-out-of-bounds is triggered.
Add a check to make sure the start address is within the bounds
- Do not use TP_printk() to boot mapped ring buffers
As a boot mapped ring buffer's data may have pointers that map to
the previous boot's memory map, it is unsafe to allow the TP_printk()
to be used to read the boot mapped buffer's events. If a TP_printk()
points to a static string from within the kernel it will not match
the current kernel mapping if KASLR is active, and it can fault.
Have it simply print out the raw fields.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ2QuXRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qncvAQDf2s2WWsy4pYp2mpRtBXvAPf6tpBdi
J9eceJQbwJVJHAEApQjEFfbUxLh2WgPU1Cn++PwDA+NLiru70+S0vtDLWwE=
=OI+v
-----END PGP SIGNATURE-----
Merge tag 'trace-ringbuffer-v6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ring-buffer fixes from Steven Rostedt:
- Fix possible overflow of mmapped ring buffer with bad offset
If the mmap() to the ring buffer passes in a start address that is
passed the end of the mmapped file, it is not caught and a
slab-out-of-bounds is triggered.
Add a check to make sure the start address is within the bounds
- Do not use TP_printk() to boot mapped ring buffers
As a boot mapped ring buffer's data may have pointers that map to the
previous boot's memory map, it is unsafe to allow the TP_printk() to
be used to read the boot mapped buffer's events. If a TP_printk()
points to a static string from within the kernel it will not match
the current kernel mapping if KASLR is active, and it can fault.
Have it simply print out the raw fields.
* tag 'trace-ringbuffer-v6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
trace/ring-buffer: Do not use TP_printk() formatting for boot mapped buffers
ring-buffer: Fix overflow in __rb_map_vma
The TP_printk() of a TRACE_EVENT() is a generic printf format that any
developer can create for their event. It may include pointers to strings
and such. A boot mapped buffer may contain data from a previous kernel
where the strings addresses are different.
One solution is to copy the event content and update the pointers by the
recorded delta, but a simpler solution (for now) is to just use the
print_fields() function to print these events. The print_fields() function
just iterates the fields and prints them according to what type they are,
and ignores the TP_printk() format from the event itself.
To understand the difference, when printing via TP_printk() the output
looks like this:
4582.696626: kmem_cache_alloc: call_site=getname_flags+0x47/0x1f0 ptr=00000000e70e10e0 bytes_req=4096 bytes_alloc=4096 gfp_flags=GFP_KERNEL node=-1 accounted=false
4582.696629: kmem_cache_alloc: call_site=alloc_empty_file+0x6b/0x110 ptr=0000000095808002 bytes_req=360 bytes_alloc=384 gfp_flags=GFP_KERNEL node=-1 accounted=false
4582.696630: kmem_cache_alloc: call_site=security_file_alloc+0x24/0x100 ptr=00000000576339c3 bytes_req=16 bytes_alloc=16 gfp_flags=GFP_KERNEL|__GFP_ZERO node=-1 accounted=false
4582.696653: kmem_cache_free: call_site=do_sys_openat2+0xa7/0xd0 ptr=00000000e70e10e0 name=names_cache
But when printing via print_fields() (echo 1 > /sys/kernel/tracing/options/fields)
the same event output looks like this:
4582.696626: kmem_cache_alloc: call_site=0xffffffff92d10d97 (-1831793257) ptr=0xffff9e0e8571e000 (-107689771147264) bytes_req=0x1000 (4096) bytes_alloc=0x1000 (4096) gfp_flags=0xcc0 (3264) node=0xffffffff (-1) accounted=(0)
4582.696629: kmem_cache_alloc: call_site=0xffffffff92d0250b (-1831852789) ptr=0xffff9e0e8577f800 (-107689770747904) bytes_req=0x168 (360) bytes_alloc=0x180 (384) gfp_flags=0xcc0 (3264) node=0xffffffff (-1) accounted=(0)
4582.696630: kmem_cache_alloc: call_site=0xffffffff92efca74 (-1829778828) ptr=0xffff9e0e8d35d3b0 (-107689640864848) bytes_req=0x10 (16) bytes_alloc=0x10 (16) gfp_flags=0xdc0 (3520) node=0xffffffff (-1) accounted=(0)
4582.696653: kmem_cache_free: call_site=0xffffffff92cfbea7 (-1831879001) ptr=0xffff9e0e8571e000 (-107689771147264) name=names_cache
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20241218141507.28389a1d@gandalf.local.home
Fixes: 07714b4bb3 ("tracing: Handle old buffer mappings for event strings and functions")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Replace trace_check_vprintf() with test_event_printk() and ignore_event()
The function test_event_printk() checks on boot up if the trace event
printf() formats dereference any pointers, and if they do, it then looks
at the arguments to make sure that the pointers they dereference will
exist in the event on the ring buffer. If they do not, it issues a
WARN_ON() as it is a likely bug.
But this isn't the case for the strings that can be dereferenced with
"%s", as some trace events (notably RCU and some IPI events) save
a pointer to a static string in the ring buffer. As the string it
points to lives as long as the kernel is running, it is not a bug
to reference it, as it is guaranteed to be there when the event is read.
But it is also possible (and a common bug) to point to some allocated
string that could be freed before the trace event is read and the
dereference is to bad memory. This case requires a run time check.
The previous way to handle this was with trace_check_vprintf() that would
process the printf format piece by piece and send what it didn't care
about to vsnprintf() to handle arguments that were not strings. This
kept it from having to reimplement vsnprintf(). But it relied on va_list
implementation and for architectures that copied the va_list and did
not pass it by reference, it wasn't even possible to do this check and
it would be skipped. As 64bit x86 passed va_list by reference, most
events were tested and this kept out bugs where strings would have been
dereferenced after being freed.
Instead of relying on the implementation of va_list, extend the boot up
test_event_printk() function to validate all the "%s" strings that
can be validated at boot, and for the few events that point to strings
outside the ring buffer, flag both the event and the field that is
dereferenced as "needs_test". Then before the event is printed, a call
to ignore_event() is made, and if the event has the flag set, it iterates
all its fields and for every field that is to be tested, it will read
the pointer directly from the event in the ring buffer and make sure
that it is valid. If the pointer is not valid, it will print a WARN_ON(),
print out to the trace that the event has unsafe memory and ignore
the print format.
With this new update, the trace_check_vprintf() can be safely removed
and now all events can be verified regardless of architecture.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZ2IqiRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qlfgAP9hJFl6zhA5GGRo905G9JWFHkbNNjgp
WfQ0oMU2Eo1q+AEAmb5d3wWfWJAa+AxiiDNeZ28En/+ZbmjhSe6fPpR4egU=
=LRKi
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
"Replace trace_check_vprintf() with test_event_printk() and
ignore_event()
The function test_event_printk() checks on boot up if the trace event
printf() formats dereference any pointers, and if they do, it then
looks at the arguments to make sure that the pointers they dereference
will exist in the event on the ring buffer. If they do not, it issues
a WARN_ON() as it is a likely bug.
But this isn't the case for the strings that can be dereferenced with
"%s", as some trace events (notably RCU and some IPI events) save a
pointer to a static string in the ring buffer. As the string it points
to lives as long as the kernel is running, it is not a bug to
reference it, as it is guaranteed to be there when the event is read.
But it is also possible (and a common bug) to point to some allocated
string that could be freed before the trace event is read and the
dereference is to bad memory. This case requires a run time check.
The previous way to handle this was with trace_check_vprintf() that
would process the printf format piece by piece and send what it didn't
care about to vsnprintf() to handle arguments that were not strings.
This kept it from having to reimplement vsnprintf(). But it relied on
va_list implementation and for architectures that copied the va_list
and did not pass it by reference, it wasn't even possible to do this
check and it would be skipped. As 64bit x86 passed va_list by
reference, most events were tested and this kept out bugs where
strings would have been dereferenced after being freed.
Instead of relying on the implementation of va_list, extend the boot
up test_event_printk() function to validate all the "%s" strings that
can be validated at boot, and for the few events that point to strings
outside the ring buffer, flag both the event and the field that is
dereferenced as "needs_test". Then before the event is printed, a call
to ignore_event() is made, and if the event has the flag set, it
iterates all its fields and for every field that is to be tested, it
will read the pointer directly from the event in the ring buffer and
make sure that it is valid. If the pointer is not valid, it will print
a WARN_ON(), print out to the trace that the event has unsafe memory
and ignore the print format.
With this new update, the trace_check_vprintf() can be safely removed
and now all events can be verified regardless of architecture"
* tag 'trace-v6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Check "%s" dereference via the field and not the TP_printk format
tracing: Add "%s" check in test_event_printk()
tracing: Add missing helper functions in event pointer dereference check
tracing: Fix test_event_printk() to process entire print argument
The TP_printk() portion of a trace event is executed at the time a event
is read from the trace. This can happen seconds, minutes, hours, days,
months, years possibly later since the event was recorded. If the print
format contains a dereference to a string via "%s", and that string was
allocated, there's a chance that string could be freed before it is read
by the trace file.
To protect against such bugs, there are two functions that verify the
event. The first one is test_event_printk(), which is called when the
event is created. It reads the TP_printk() format as well as its arguments
to make sure nothing may be dereferencing a pointer that was not copied
into the ring buffer along with the event. If it is, it will trigger a
WARN_ON().
For strings that use "%s", it is not so easy. The string may not reside in
the ring buffer but may still be valid. Strings that are static and part
of the kernel proper which will not be freed for the life of the running
system, are safe to dereference. But to know if it is a pointer to a
static string or to something on the heap can not be determined until the
event is triggered.
This brings us to the second function that tests for the bad dereferencing
of strings, trace_check_vprintf(). It would walk through the printf format
looking for "%s", and when it finds it, it would validate that the pointer
is safe to read. If not, it would produces a WARN_ON() as well and write
into the ring buffer "[UNSAFE-MEMORY]".
The problem with this is how it used va_list to have vsnprintf() handle
all the cases that it didn't need to check. Instead of re-implementing
vsnprintf(), it would make a copy of the format up to the %s part, and
call vsnprintf() with the current va_list ap variable, where the ap would
then be ready to point at the string in question.
For architectures that passed va_list by reference this was possible. For
architectures that passed it by copy it was not. A test_can_verify()
function was used to differentiate between the two, and if it wasn't
possible, it would disable it.
Even for architectures where this was feasible, it was a stretch to rely
on such a method that is undocumented, and could cause issues later on
with new optimizations of the compiler.
Instead, the first function test_event_printk() was updated to look at
"%s" as well. If the "%s" argument is a pointer outside the event in the
ring buffer, it would find the field type of the event that is the problem
and mark the structure with a new flag called "needs_test". The event
itself will be marked by TRACE_EVENT_FL_TEST_STR to let it be known that
this event has a field that needs to be verified before the event can be
printed using the printf format.
When the event fields are created from the field type structure, the
fields would copy the field type's "needs_test" value.
Finally, before being printed, a new function ignore_event() is called
which will check if the event has the TEST_STR flag set (if not, it
returns false). If the flag is set, it then iterates through the events
fields looking for the ones that have the "needs_test" flag set.
Then it uses the offset field from the field structure to find the pointer
in the ring buffer event. It runs the tests to make sure that pointer is
safe to print and if not, it triggers the WARN_ON() and also adds to the
trace output that the event in question has an unsafe memory access.
The ignore_event() makes the trace_check_vprintf() obsolete so it is
removed.
Link: https://lore.kernel.org/all/CAHk-=wh3uOnqnZPpR0PeLZZtyWbZLboZ7cHLCKRWsocvs9Y7hQ@mail.gmail.com/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20241217024720.848621576@goodmis.org
Fixes: 5013f454a3 ("tracing: Add check of trace event print fmts for dereferencing pointers")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The test_event_printk() code makes sure that when a trace event is
registered, any dereferenced pointers in from the event's TP_printk() are
pointing to content in the ring buffer. But currently it does not handle
"%s", as there's cases where the string pointer saved in the ring buffer
points to a static string in the kernel that will never be freed. As that
is a valid case, the pointer needs to be checked at runtime.
Currently the runtime check is done via trace_check_vprintf(), but to not
have to replicate everything in vsnprintf() it does some logic with the
va_list that may not be reliable across architectures. In order to get rid
of that logic, more work in the test_event_printk() needs to be done. Some
of the strings can be validated at this time when it is obvious the string
is valid because the string will be saved in the ring buffer content.
Do all the validation of strings in the ring buffer at boot in
test_event_printk(), and make sure that the field of the strings that
point into the kernel are accessible. This will allow adding checks at
runtime that will validate the fields themselves and not rely on paring
the TP_printk() format at runtime.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20241217024720.685917008@goodmis.org
Fixes: 5013f454a3 ("tracing: Add check of trace event print fmts for dereferencing pointers")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The process_pointer() helper function looks to see if various trace event
macros are used. These macros are for storing data in the event. This
makes it safe to dereference as the dereference will then point into the
event on the ring buffer where the content of the data stays with the
event itself.
A few helper functions were missing. Those were:
__get_rel_dynamic_array()
__get_dynamic_array_len()
__get_rel_dynamic_array_len()
__get_rel_sockaddr()
Also add a helper function find_print_string() to not need to use a middle
man variable to test if the string exists.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20241217024720.521836792@goodmis.org
Fixes: 5013f454a3 ("tracing: Add check of trace event print fmts for dereferencing pointers")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The test_event_printk() analyzes print formats of trace events looking for
cases where it may dereference a pointer that is not in the ring buffer
which can possibly be a bug when the trace event is read from the ring
buffer and the content of that pointer no longer exists.
The function needs to accurately go from one print format argument to the
next. It handles quotes and parenthesis that may be included in an
argument. When it finds the start of the next argument, it uses a simple
"c = strstr(fmt + i, ',')" to find the end of that argument!
In order to include "%s" dereferencing, it needs to process the entire
content of the print format argument and not just the content of the first
',' it finds. As there may be content like:
({ const char *saved_ptr = trace_seq_buffer_ptr(p); static const char
*access_str[] = { "---", "--x", "w--", "w-x", "-u-", "-ux", "wu-", "wux"
}; union kvm_mmu_page_role role; role.word = REC->role;
trace_seq_printf(p, "sp gen %u gfn %llx l%u %u-byte q%u%s %s%s" " %snxe
%sad root %u %s%c", REC->mmu_valid_gen, REC->gfn, role.level,
role.has_4_byte_gpte ? 4 : 8, role.quadrant, role.direct ? " direct" : "",
access_str[role.access], role.invalid ? " invalid" : "", role.efer_nx ? ""
: "!", role.ad_disabled ? "!" : "", REC->root_count, REC->unsync ?
"unsync" : "sync", 0); saved_ptr; })
Which is an example of a full argument of an existing event. As the code
already handles finding the next print format argument, process the
argument at the end of it and not the start of it. This way it has both
the start of the argument as well as the end of it.
Add a helper function "process_pointer()" that will do the processing during
the loop as well as at the end. It also makes the code cleaner and easier
to read.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20241217024720.362271189@goodmis.org
Fixes: 5013f454a3 ("tracing: Add check of trace event print fmts for dereferencing pointers")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When function tracing and function graph tracing are both enabled (in
different instances) the "parent" of some of the function tracing events
is "return_to_handler" which is the trampoline used by function graph
tracing. To fix this, ftrace_get_true_parent_ip() was introduced that
returns the "true" parent ip instead of the trampoline.
To do this, the ftrace_regs_get_stack_pointer() is used, which uses
kernel_stack_pointer(). The problem is that microblaze does not implement
kerenl_stack_pointer() so when function graph tracing is enabled, the
build fails. But microblaze also does not enabled HAVE_DYNAMIC_FTRACE_WITH_ARGS.
That option has to be enabled by the architecture to reliably get the
values from the fregs parameter passed in. When that config is not set,
the architecture can also pass in NULL, which is not tested for in that
function and could cause the kernel to crash.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Jeff Xie <jeff.xie@linux.dev>
Link: https://lore.kernel.org/20241216164633.6df18e87@gandalf.local.home
Fixes: 60b1f578b5 ("ftrace: Get the true parent ip for function tracer")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
A bug was discovered where the idle shadow stacks were not initialized
for offline CPUs when starting function graph tracer, and when they came
online they were not traced due to the missing shadow stack. To fix
this, the idle task shadow stack initialization was moved to using the
CPU hotplug callbacks. But it removed the initialization when the
function graph was enabled. The problem here is that the hotplug
callbacks are called when the CPUs come online, but the idle shadow
stack initialization only happens if function graph is currently
active. This caused the online CPUs to not get their shadow stack
initialized.
The idle shadow stack initialization still needs to be done when the
function graph is registered, as they will not be allocated if function
graph is not registered.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241211135335.094ba282@batman.local.home
Fixes: 2c02f7375e ("fgraph: Use CPU hotplug mechanism to initialize idle shadow stacks")
Reported-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Closes: https://lore.kernel.org/all/CACRpkdaTBrHwRbbrphVy-=SeDz6MSsXhTKypOtLrTQ+DgGAOcQ@mail.gmail.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Fix a bug in the BPF verifier to track changes to packet data
property for global functions (Eduard Zingerman)
- Fix a theoretical BPF prog_array use-after-free in RCU handling
of __uprobe_perf_func (Jann Horn)
- Fix BPF tracing to have an explicit list of tracepoints and
their arguments which need to be annotated as PTR_MAYBE_NULL
(Kumar Kartikeya Dwivedi)
- Fix a logic bug in the bpf_remove_insns code where a potential
error would have been wrongly propagated (Anton Protopopov)
- Avoid deadlock scenarios caused by nested kprobe and fentry
BPF programs (Priya Bala Govindasamy)
- Fix a bug in BPF verifier which was missing a size check for
BTF-based context access (Kumar Kartikeya Dwivedi)
- Fix a crash found by syzbot through an invalid BPF prog_array
access in perf_event_detach_bpf_prog (Jiri Olsa)
- Fix several BPF sockmap bugs including a race causing a
refcount imbalance upon element replace (Michal Luczaj)
- Fix a use-after-free from mismatching BPF program/attachment
RCU flavors (Jann Horn)
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
-----BEGIN PGP SIGNATURE-----
iIsEABYKADMWIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZ13rdhUcZGFuaWVsQGlv
Z2VhcmJveC5uZXQACgkQ2yufC7HISINfqAD7B2vX6EgTFrgy7QDepQnZsmu2qjdW
fFUzPatFXXp2S3MA/16vOEoHJ4rRhBkcUK/vw3gyY5j5bYZNUTTaam5l4BcM
=gkfb
-----END PGP SIGNATURE-----
Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Daniel Borkmann:
- Fix a bug in the BPF verifier to track changes to packet data
property for global functions (Eduard Zingerman)
- Fix a theoretical BPF prog_array use-after-free in RCU handling of
__uprobe_perf_func (Jann Horn)
- Fix BPF tracing to have an explicit list of tracepoints and their
arguments which need to be annotated as PTR_MAYBE_NULL (Kumar
Kartikeya Dwivedi)
- Fix a logic bug in the bpf_remove_insns code where a potential error
would have been wrongly propagated (Anton Protopopov)
- Avoid deadlock scenarios caused by nested kprobe and fentry BPF
programs (Priya Bala Govindasamy)
- Fix a bug in BPF verifier which was missing a size check for
BTF-based context access (Kumar Kartikeya Dwivedi)
- Fix a crash found by syzbot through an invalid BPF prog_array access
in perf_event_detach_bpf_prog (Jiri Olsa)
- Fix several BPF sockmap bugs including a race causing a refcount
imbalance upon element replace (Michal Luczaj)
- Fix a use-after-free from mismatching BPF program/attachment RCU
flavors (Jann Horn)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (23 commits)
bpf: Avoid deadlock caused by nested kprobe and fentry bpf programs
selftests/bpf: Add tests for raw_tp NULL args
bpf: Augment raw_tp arguments with PTR_MAYBE_NULL
bpf: Revert "bpf: Mark raw_tp arguments with PTR_MAYBE_NULL"
selftests/bpf: Add test for narrow ctx load for pointer args
bpf: Check size for BTF-based ctx access of pointer members
selftests/bpf: extend changes_pkt_data with cases w/o subprograms
bpf: fix null dereference when computing changes_pkt_data of prog w/o subprogs
bpf: Fix theoretical prog_array UAF in __uprobe_perf_func()
bpf: fix potential error return
selftests/bpf: validate that tail call invalidates packet pointers
bpf: consider that tail calls invalidate packet pointers
selftests/bpf: freplace tests for tracking of changes_packet_data
bpf: check changes_pkt_data property for extension programs
selftests/bpf: test for changing packet data from global functions
bpf: track changes_pkt_data property for global functions
bpf: refactor bpf_helper_changes_pkt_data to use helper number
bpf: add find_containing_subprog() utility function
bpf,perf: Fix invalid prog_array access in perf_event_detach_bpf_prog
bpf: Fix UAF via mismatching bpf_prog/attachment RCU flavors
...
- eprobes: Fix to release eprobe when failed to add dyn_event.
This unregisters event call and release eprobe when it fails to add
a dynamic event. Found in cleaning up.
-----BEGIN PGP SIGNATURE-----
iQFPBAABCgA5FiEEh7BulGwFlgAOi5DV2/sHvwUrPxsFAmdYT3sbHG1hc2FtaS5o
aXJhbWF0c3VAZ21haWwuY29tAAoJENv7B78FKz8b5X8IALRigb6oDLzrq8yavSPy
xn1QlnRtRFdLz+PQ3kFCzU3TOT9oxdFhBkYAXS32vDItPqzM7Upj0oZceqhmd5kz
aXSdkL+PFmbHuLzyPuBksyX4gKga06rQBHJ2SIPxnRPZcXBBRStqyWRDpNjwIxrW
K8p6k0Agrtd4tL7QtBdukda0uJqKSjN3gOzRAu40KMBjBJZ3kMTsoc+GWGIoIMHb
PIDaXTZT0DlZ9ZxiEA/gPcjMugNjDVhkbq2ChPU+asvlRs0YUANT4CF0HcntJvDO
W0xIWivfYIKWFLdAn6fhXicPkqU9DQ7FjppyRKC6y4bwuCYJlSeLsPmSWNI2IEBX
bFA=
=LLWX
-----END PGP SIGNATURE-----
Merge tag 'probes-fixes-v6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull eprobes fix from Masami Hiramatsu:
- release eprobe when failing to add dyn_event.
This unregisters event call and release eprobe when it fails to add a
dynamic event. Found in cleaning up.
* tag 'probes-fixes-v6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/eprobe: Fix to release eprobe when failed to add dyn_event
Currently, the pointer stored in call->prog_array is loaded in
__uprobe_perf_func(), with no RCU annotation and no immediately visible
RCU protection, so it looks as if the loaded pointer can immediately be
dangling.
Later, bpf_prog_run_array_uprobe() starts a RCU-trace read-side critical
section, but this is too late. It then uses rcu_dereference_check(), but
this use of rcu_dereference_check() does not actually dereference anything.
Fix it by aligning the semantics to bpf_prog_run_array(): Let the caller
provide rcu_read_lock_trace() protection and then load call->prog_array
with rcu_dereference_check().
This issue seems to be theoretical: I don't know of any way to reach this
code without having handle_swbp() further up the stack, which is already
holding a rcu_read_lock_trace() lock, so where we take
rcu_read_lock_trace() in __uprobe_perf_func()/bpf_prog_run_array_uprobe()
doesn't actually have any effect.
Fixes: 8c7dcb84e3 ("bpf: implement sleepable uprobes by chaining gps")
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241210-bpf-fix-uprobe-uaf-v4-1-5fc8959b2b74@google.com
Syzbot reported [1] crash that happens for following tracing scenario:
- create tracepoint perf event with attr.inherit=1, attach it to the
process and set bpf program to it
- attached process forks -> chid creates inherited event
the new child event shares the parent's bpf program and tp_event
(hence prog_array) which is global for tracepoint
- exit both process and its child -> release both events
- first perf_event_detach_bpf_prog call will release tp_event->prog_array
and second perf_event_detach_bpf_prog will crash, because
tp_event->prog_array is NULL
The fix makes sure the perf_event_detach_bpf_prog checks prog_array
is valid before it tries to remove the bpf program from it.
[1] https://lore.kernel.org/bpf/Z1MR6dCIKajNS6nU@krava/T/#m91dbf0688221ec7a7fc95e896a7ef9ff93b0b8ad
Fixes: 0ee288e69d ("bpf,perf: Fix perf_event_detach_bpf_prog error handling")
Reported-by: syzbot+2e0d2840414ce817aaac@syzkaller.appspotmail.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241208142507.1207698-1-jolsa@kernel.org
Uprobes always use bpf_prog_run_array_uprobe() under tasks-trace-RCU
protection. But it is possible to attach a non-sleepable BPF program to a
uprobe, and non-sleepable BPF programs are freed via normal RCU (see
__bpf_prog_put_noref()). This leads to UAF of the bpf_prog because a normal
RCU grace period does not imply a tasks-trace-RCU grace period.
Fix it by explicitly waiting for a tasks-trace-RCU grace period after
removing the attachment of a bpf_prog to a perf_event.
Fixes: 8c7dcb84e3 ("bpf: implement sleepable uprobes by chaining gps")
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/bpf/20241210-bpf-fix-actual-uprobe-uaf-v1-1-19439849dd44@google.com
Tracepoints require having RCU "watching" as it uses RCU to do updates to
the tracepoints. There are some cases that would call a tracepoint when
RCU was not "watching". This was usually in the idle path where RCU has
"shutdown". For the few locations that had tracepoints without RCU
watching, there was an trace_*_rcuidle() variant that could be used. This
used SRCU for protection.
There are tracepoints that trace when interrupts and preemption are
enabled and disabled. In some architectures, these tracepoints are called
in a path where RCU is not watching. When x86 and arm64 removed these
locations, it was incorrectly assumed that it would be safe to remove the
trace_*_rcuidle() variant and also remove the SRCU logic, as it made the
code more complex and harder to implement new tracepoint features (like
faultable tracepoints and tracepoints in rust).
Instead of bringing back the trace_*_rcuidle(), as it will not be trivial
to do as new code has already been added depending on its removal, add a
workaround to the one file that still requires it (trace_preemptirq.c). If
the architecture does not define CONFIG_ARCH_WANTS_NO_INSTR, then check if
the code is in the idle path, and if so, call ct_irq_enter/exit() which
will enable RCU around the tracepoint.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/20241204100414.4d3e06d0@gandalf.local.home
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: 48bcda6848 ("tracing: Remove definition of trace_*_rcuidle()")
Closes: https://lore.kernel.org/all/bddb02de-957a-4df5-8e77-829f55728ea2@roeck-us.net/
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The cmp_entries_dup() function used as the comparator for sort()
violated the symmetry and transitivity properties required by the
sorting algorithm. Specifically, it returned 1 whenever memcmp() was
non-zero, which broke the following expectations:
* Symmetry: If x < y, then y > x.
* Transitivity: If x < y and y < z, then x < z.
These violations could lead to incorrect sorting and failure to
correctly identify duplicate elements.
Fix the issue by directly returning the result of memcmp(), which
adheres to the required comparison properties.
Cc: stable@vger.kernel.org
Fixes: 08d43a5fa0 ("tracing: Add lock-free tracing_map")
Link: https://lore.kernel.org/20241203202228.1274403-1-visitorckw@gmail.com
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
With bpf_get_probe_write_proto() no longer printing a message, we can
avoid it being a special case with its own permission check.
Refactor bpf_tracing_func_proto() similar to bpf_base_func_proto() to
have a section conditional on bpf_token_capable(CAP_SYS_ADMIN), where
the proto for bpf_probe_write_user() is returned. Finally, remove the
unnecessary bpf_get_probe_write_proto().
This simplifies the code, and adding additional CAP_SYS_ADMIN-only
helpers in future avoids duplicating the same CAP_SYS_ADMIN check.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20241129090040.2690691-2-elver@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The warning message for bpf_probe_write_user() was introduced in
96ae522795 ("bpf: Add bpf_probe_write_user BPF helper to be called in
tracers"), with the following in the commit message:
Given this feature is meant for experiments, and it has a risk of
crashing the system, and running programs, we print a warning on
when a proglet that attempts to use this helper is installed,
along with the pid and process name.
After 8 years since 96ae522795, bpf_probe_write_user() has found
successful applications beyond experiments [1, 2], with no other good
alternatives. Despite its intended purpose for "experiments", that
doesn't stop Hyrum's law, and there are likely many more users depending
on this helper: "[..] it does not matter what you promise [..] all
observable behaviors of your system will be depended on by somebody."
The ominous "helper that may corrupt user memory!" has offered no real
benefit, and has been found to lead to confusion where the system
administrator is loading programs with valid use cases.
As such, remove the warning message.
Link: https://lore.kernel.org/lkml/20240404190146.1898103-1-elver@google.com/ [1]
Link: https://lore.kernel.org/r/lkml/CAAn3qOUMD81-vxLLfep0H6rRd74ho2VaekdL4HjKq+Y1t9KdXQ@mail.gmail.com/ [2]
Link: https://lore.kernel.org/all/CAEf4Bzb4D_=zuJrg3PawMOW3KqF8JvJm9SwF81_XHR2+u5hkUg@mail.gmail.com/
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20241129090040.2690691-1-elver@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The pid_max sysctl is a global value. For a long time the default value
has been 65535 and during the pidfd dicussions Linus proposed to bump
pid_max by default (cf. [1]). Based on this discussion systemd started
bumping pid_max to 2^22. So all new systems now run with a very high
pid_max limit with some distros having also backported that change.
The decision to bump pid_max is obviously correct. It just doesn't make
a lot of sense nowadays to enforce such a low pid number. There's
sufficient tooling to make selecting specific processes without typing
really large pid numbers available.
In any case, there are workloads that have expections about how large
pid numbers they accept. Either for historical reasons or architectural
reasons. One concreate example is the 32-bit version of Android's bionic
libc which requires pid numbers less than 65536. There are workloads
where it is run in a 32-bit container on a 64-bit kernel. If the host
has a pid_max value greater than 65535 the libc will abort thread
creation because of size assumptions of pthread_mutex_t.
That's a fairly specific use-case however, in general specific workloads
that are moved into containers running on a host with a new kernel and a
new systemd can run into issues with large pid_max values. Obviously
making assumptions about the size of the allocated pid is suboptimal but
we have userspace that does it.
Of course, giving containers the ability to restrict the number of
processes in their respective pid namespace indepent of the global limit
through pid_max is something desirable in itself and comes in handy in
general.
Independent of motivating use-cases the existence of pid namespaces
makes this also a good semantical extension and there have been prior
proposals pushing in a similar direction.
The trick here is to minimize the risk of regressions which I think is
doable. The fact that pid namespaces are hierarchical will help us here.
What we mostly care about is that when the host sets a low pid_max
limit, say (crazy number) 100 that no descendant pid namespace can
allocate a higher pid number in its namespace. Since pid allocation is
hierarchial this can be ensured by checking each pid allocation against
the pid namespace's pid_max limit. This means if the allocation in the
descendant pid namespace succeeds, the ancestor pid namespace can reject
it. If the ancestor pid namespace has a higher limit than the descendant
pid namespace the descendant pid namespace will reject the pid
allocation. The ancestor pid namespace will obviously not care about
this.
All in all this means pid_max continues to enforce a system wide limit
on the number of processes but allows pid namespaces sufficient leeway
in handling workloads with assumptions about pid values and allows
containers to restrict the number of processes in a pid namespace
through the pid_max interface.
[1]: https://lore.kernel.org/linux-api/CAHk-=wiZ40LVjnXSi9iHLE_-ZBsWFGCgdmNiYZUXn1-V5YBg2g@mail.gmail.com
- rebased from 5.14-rc1
- a few fixes (missing ns_free_inum on error path, missing initialization, etc)
- permission check changes in pid_table_root_permissions
- unsigned int pid_max -> int pid_max (keep pid_max type as it was)
- add READ_ONCE in alloc_pid() as suggested by Christian
- rebased from 6.7 and take into account:
* sysctl: treewide: drop unused argument ctl_table_root::set_ownership(table)
* sysctl: treewide: constify ctl_table_header::ctl_table_arg
* pidfd: add pidfs
* tracing: Move saved_cmdline code into trace_sched_switch.c
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Link: https://lore.kernel.org/r/20241122132459.135120-2-aleksandr.mikhalitsyn@canonical.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
The scheduler added NEED_RESCHED_LAZY scheduling. Record this state as
part of trace flags and expose it in the need_resched field.
Record and expose NEED_RESCHED_LAZY.
[bigeasy: Commit description, documentation bits.]
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241122202849.7DfYpJR0@linutronix.de
Reviewed-by: Ankur Arora <ankur.a.arora@oracle.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Addition of faultable tracepoints
There's a tracepoint attached to both a system call entry and exit. This
location is known to allow page faults. The tracepoints are called under
an rcu_read_lock() which does not allow faults that can sleep. This limits
the ability of tracepoint handlers to page fault in user space system call
parameters. Now these tracepoints have been made "faultable", allowing the
callbacks to fault in user space parameters and record them.
Note, only the infrastructure has been implemented. The consumers (perf,
ftrace, BPF) now need to have their code modified to allow faults.
- Fix up of BPF code for the tracepoint faultable logic
- Update tracepoints to use the new static branch API
- Remove trace_*_rcuidle() variants and the SRCU protection they used
- Remove unused TRACE_EVENT_FL_FILTERED logic
- Replace strncpy() with strscpy() and memcpy()
- Use replace per_cpu_ptr(smp_processor_id()) with this_cpu_ptr()
- Fix perf events to not duplicate samples when tracing is enabled
- Replace atomic64_add_return(1, counter) with atomic64_inc_return(counter)
- Make stack trace buffer 4K instead of PAGE_SIZE
- Remove TRACE_FLAG_IRQS_NOSUPPORT flag as it was never used
- Get the true return address for function tracer when function graph tracer
is also running.
When function_graph trace is running along with function tracer,
the parent function of the function tracer sometimes is
"return_to_handler", which is the function graph trampoline to record
the exit of the function. Use existing logic that calls into the
fgraph infrastructure to find the real return address.
- Remove (un)regfunc pointers out of tracepoint structure
- Added last minute bug fix for setting pending modules in stack function
filter.
echo "write*:mod:ext3" > /sys/kernel/tracing/stack_trace_filter
Would cause a kernel NULL dereference.
- Minor clean ups
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZz6dehQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qlQsAP9aB0XGUV3UykvjZuKK84VDZ26a2hZH
X2JDYsNA4luuPAEAz/BG2rnslfMZ04WTMAl8h1eh10lxcuHG0wQMHVBXIwI=
=lzb5
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing updates from Steven Rostedt:
- Addition of faultable tracepoints
There's a tracepoint attached to both a system call entry and exit.
This location is known to allow page faults. The tracepoints are
called under an rcu_read_lock() which does not allow faults that can
sleep. This limits the ability of tracepoint handlers to page fault
in user space system call parameters. Now these tracepoints have been
made "faultable", allowing the callbacks to fault in user space
parameters and record them.
Note, only the infrastructure has been implemented. The consumers
(perf, ftrace, BPF) now need to have their code modified to allow
faults.
- Fix up of BPF code for the tracepoint faultable logic
- Update tracepoints to use the new static branch API
- Remove trace_*_rcuidle() variants and the SRCU protection they used
- Remove unused TRACE_EVENT_FL_FILTERED logic
- Replace strncpy() with strscpy() and memcpy()
- Use replace per_cpu_ptr(smp_processor_id()) with this_cpu_ptr()
- Fix perf events to not duplicate samples when tracing is enabled
- Replace atomic64_add_return(1, counter) with
atomic64_inc_return(counter)
- Make stack trace buffer 4K instead of PAGE_SIZE
- Remove TRACE_FLAG_IRQS_NOSUPPORT flag as it was never used
- Get the true return address for function tracer when function graph
tracer is also running.
When function_graph trace is running along with function tracer, the
parent function of the function tracer sometimes is
"return_to_handler", which is the function graph trampoline to record
the exit of the function. Use existing logic that calls into the
fgraph infrastructure to find the real return address.
- Remove (un)regfunc pointers out of tracepoint structure
- Added last minute bug fix for setting pending modules in stack
function filter.
echo "write*:mod:ext3" > /sys/kernel/tracing/stack_trace_filter
Would cause a kernel NULL dereference.
- Minor clean ups
* tag 'trace-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (31 commits)
ftrace: Fix regression with module command in stack_trace_filter
tracing: Fix function name for trampoline
ftrace: Get the true parent ip for function tracer
tracing: Remove redundant check on field->field in histograms
bpf: ensure RCU Tasks Trace GP for sleepable raw tracepoint BPF links
bpf: decouple BPF link/attach hook and BPF program sleepable semantics
bpf: put bpf_link's program when link is safe to be deallocated
tracing: Replace strncpy() with strscpy() when copying comm
tracing: Add might_fault() check in __DECLARE_TRACE_SYSCALL
tracing: Fix syscall tracepoint use-after-free
tracing: Introduce tracepoint_is_faultable()
tracing: Introduce tracepoint extended structure
tracing: Remove TRACE_FLAG_IRQS_NOSUPPORT
tracing: Replace multiple deprecated strncpy with memcpy
tracing: Make percpu stack trace buffer invariant to PAGE_SIZE
tracing: Use atomic64_inc_return() in trace_clock_counter()
trace/trace_event_perf: remove duplicate samples on the first tracepoint event
tracing/bpf: Add might_fault check to syscall probes
tracing/perf: Add might_fault check to syscall probes
tracing/ftrace: Add might_fault check to syscall probes
...
- Add ':' to getopt option 'trace-buffer-size' in timerlat_hist for
consistency
- Remove unused sched_getattr define
- Rename sched_setattr() helper to syscall_sched_setattr() to avoid
conflicts
- Update counters to long from int to avoid overflow
- Add libcpupower dependency detection
- Add --deepest-idle-state to timerlat to limit deep idle sleeps
- Other minor clean ups and documentation changes
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZz5O/hQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qkLlAQDAJ0MASrdbJRDrLrfmKX6sja582MLe
3MvevdSkOeXRdQEA0tzm46KOb5/aYNotzpntQVkTjuZiPBHSgn1JzASiaAI=
=OZ1w
-----END PGP SIGNATURE-----
Merge tag 'trace-tools-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing tools updates from Steven Rostedt:
- Add ':' to getopt option 'trace-buffer-size' in timerlat_hist for
consistency
- Remove unused sched_getattr define
- Rename sched_setattr() helper to syscall_sched_setattr() to avoid
conflicts
- Update counters to long from int to avoid overflow
- Add libcpupower dependency detection
- Add --deepest-idle-state to timerlat to limit deep idle sleeps
- Other minor clean ups and documentation changes
* tag 'trace-tools-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
verification/dot2: Improve dot parser robustness
tools/rtla: Improve exception handling in timerlat_load.py
tools/rtla: Enhance argument parsing in timerlat_load.py
tools/rtla: Improve code readability in timerlat_load.py
rtla/timerlat: Do not set params->user_workload with -U
rtla: Documentation: Mention --deepest-idle-state
rtla/timerlat: Add --deepest-idle-state for hist
rtla/timerlat: Add --deepest-idle-state for top
rtla/utils: Add idle state disabling via libcpupower
rtla: Add optional dependency on libcpupower
tools/build: Add libcpupower dependency detection
rtla/timerlat: Make timerlat_hist_cpu->*_count unsigned long long
rtla/timerlat: Make timerlat_top_cpu->*_count unsigned long long
tools/rtla: fix collision with glibc sched_attr/sched_set_attr
tools/rtla: drop __NR_sched_getattr
rtla: Fix consistency in getopt_long for timerlat_hist
rv: Fix a typo
tools/rv: Correct the grammatical errors in the comments
tools/rv: Correct the grammatical errors in the comments
rtla: use the definition for stdout fd when calling isatty()
- Limit time interrupts are disabled in rb_check_pages()
The rb_check_pages() is called after the ring buffer size is updated to
make sure that the ring buffer has not been corrupted. Commit
c2274b908d ("ring-buffer: Fix a race between readers and resize
checks") fixed a race with the check pages and simultaneous resizes to the
ring buffer by adding a raw_spin_lock_irqsave() around the check
operation. Although this was a simple fix, it would hold interrupts
disabled for non determinative amount of time. This could harm PREEMPT_RT
operations.
Instead, modify the logic by adding a counter when the buffer is modified
and to release the raw_spin_lock() at each iteration. It checks the
counter under the lock to see if a modification happened during the loop,
and if it did, it would restart the loop up to 3 times. After 3 times, it
will simply exit the check, as it is unlikely that would ever happen as
buffer resizes are rare occurrences.
- Replace some open coded str_low_high() with the helper
- Fix some documentation/comments
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZz5KNxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qiANAP4/6cSGOhQgIkaN8UsKmWTfBqU89JK2
a4tqAZWKsQormgEAkDLPD0Lda0drmu/Dwnr/klS21yyLcQBzyX1CYw9G4gY=
=jkLz
-----END PGP SIGNATURE-----
Merge tag 'trace-ring-buffer-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull trace ring-buffer updates from Steven Rostedt:
- Limit time interrupts are disabled in rb_check_pages()
rb_check_pages() is called after the ring buffer size is updated to
make sure that the ring buffer has not been corrupted. Commit
c2274b908d ("ring-buffer: Fix a race between readers and resize
checks") fixed a race with the check pages and simultaneous resizes
to the ring buffer by adding a raw_spin_lock_irqsave() around the
check operation. Although this was a simple fix, it would hold
interrupts disabled for non determinative amount of time. This could
harm PREEMPT_RT operations.
Instead, modify the logic by adding a counter when the buffer is
modified and to release the raw_spin_lock() at each iteration. It
checks the counter under the lock to see if a modification happened
during the loop, and if it did, it would restart the loop up to 3
times. After 3 times, it will simply exit the check, as it is
unlikely that would ever happen as buffer resizes are rare
occurrences.
- Replace some open coded str_low_high() with the helper
- Fix some documentation/comments
* tag 'trace-ring-buffer-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Correct a grammatical error in a comment
ring-buffer: Use str_low_high() helper in ring_buffer_producer()
ring-buffer: Reorganize kerneldoc parameter names
ring-buffer: Limit time with disabled interrupts in rb_check_pages()
-----BEGIN PGP SIGNATURE-----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=TXGS
-----END PGP SIGNATURE-----
Merge tag 'bpf-next-6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Add BPF uprobe session support (Jiri Olsa)
- Optimize uprobe performance (Andrii Nakryiko)
- Add bpf_fastcall support to helpers and kfuncs (Eduard Zingerman)
- Avoid calling free_htab_elem() under hash map bucket lock (Hou Tao)
- Prevent tailcall infinite loop caused by freplace (Leon Hwang)
- Mark raw_tracepoint arguments as nullable (Kumar Kartikeya Dwivedi)
- Introduce uptr support in the task local storage map (Martin KaFai
Lau)
- Stringify errno log messages in libbpf (Mykyta Yatsenko)
- Add kmem_cache BPF iterator for perf's lock profiling (Namhyung Kim)
- Support BPF objects of either endianness in libbpf (Tony Ambardar)
- Add ksym to struct_ops trampoline to fix stack trace (Xu Kuohai)
- Introduce private stack for eligible BPF programs (Yonghong Song)
- Migrate samples/bpf tests to selftests/bpf test_progs (Daniel T. Lee)
- Migrate test_sock to selftests/bpf test_progs (Jordan Rife)
* tag 'bpf-next-6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (152 commits)
libbpf: Change hash_combine parameters from long to unsigned long
selftests/bpf: Fix build error with llvm 19
libbpf: Fix memory leak in bpf_program__attach_uprobe_multi
bpf: use common instruction history across all states
bpf: Add necessary migrate_disable to range_tree.
bpf: Do not alloc arena on unsupported arches
selftests/bpf: Set test path for token/obj_priv_implicit_token_envvar
selftests/bpf: Add a test for arena range tree algorithm
bpf: Introduce range_tree data structure and use it in bpf arena
samples/bpf: Remove unused variable in xdp2skb_meta_kern.c
samples/bpf: Remove unused variables in tc_l2_redirect_kern.c
bpftool: Cast variable `var` to long long
bpf, x86: Propagate tailcall info only for subprogs
bpf: Add kernel symbol for struct_ops trampoline
bpf: Use function pointers count as struct_ops links count
bpf: Remove unused member rcu from bpf_struct_ops_map
selftests/bpf: Add struct_ops prog private stack tests
bpf: Support private stack for struct_ops progs
selftests/bpf: Add tracing prog private stack tests
bpf, x86: Support private stack in jit
...
A relatively modest collection of changes:
* Adopt kstrtoint() and kstrtol() instead of the simple_strtoXX family
for better error checking of user input.
* Align the print behavour when breakpoints are enabled and disabled by
adopting the current behaviour of breakpoint disable for both.
* Remove some of the (rather odd and user hostile) hex fallbacks and
require kdb users to prefix with 0x instead.
* Tidy up (and fix) control code handling in kdb's keyboard code. This
makes the control code handling at the keyboard behave the same way
as it does via the UART.
* Switch my own entry in MAINTAINERS to my @kernel.org address.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
-----BEGIN PGP SIGNATURE-----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=rlg/
-----END PGP SIGNATURE-----
Merge tag 'kgdb-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux
Pull kgdb updates from Daniel Thompson:
"A relatively modest collection of changes:
- Adopt kstrtoint() and kstrtol() instead of the simple_strtoXX
family for better error checking of user input.
- Align the print behavour when breakpoints are enabled and disabled
by adopting the current behaviour of breakpoint disable for both.
- Remove some of the (rather odd and user hostile) hex fallbacks and
require kdb users to prefix with 0x instead.
- Tidy up (and fix) control code handling in kdb's keyboard code.
This makes the control code handling at the keyboard behave the
same way as it does via the UART.
- Switch my own entry in MAINTAINERS to my @kernel.org address"
* tag 'kgdb-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
kdb: fix ctrl+e/a/f/b/d/p/n broken in keyboard mode
MAINTAINERS: Use Daniel Thompson's korg address for kgdb work
kdb: Fix breakpoint enable to be silent if already enabled
kdb: Remove fallback interpretation of arbitrary numbers as hex
trace: kdb: Replace simple_strtoul with kstrtoul in kdb_ftdump
kdb: Replace the use of simple_strto with safer kstrto in kdb_main
- Merged tag ftrace-v6.12-rc4
There was a fix to locking in register_ftrace_graph() for shadow stacks
that was sent upstream. But this code was also being rewritten, and the
locking fix was needed. Merging this fix was required to continue the
work.
- Restructure the function graph shadow stack to prepare it for use with
kretprobes
With the goal of merging the shadow stack logic of function graph and
kretprobes, some more restructuring of the function shadow stack is
required.
Move out function graph specific fields from the fgraph infrastructure and
store it on the new stack variables that can pass data from the entry
callback to the exit callback.
Hopefully, with this change, the merge of kretprobes to use fgraph shadow
stacks will be ready by the next merge window.
- Make shadow stack 4k instead of using PAGE_SIZE.
Some architectures have very large PAGE_SIZE values which make its use for
shadow stacks waste a lot of memory.
- Give shadow stacks its own kmem cache.
When function graph is started, every task on the system gets a shadow
stack. In the future, shadow stacks may not be 4K in size. Have it have
its own kmem cache so that whatever size it becomes will still be
efficient in allocations.
- Initialize profiler graph ops as it will be needed for new updates to fgraph
- Convert to use guard(mutex) for several ftrace and fgraph functions
- Add more comments and documentation
- Show function return address in function graph tracer
Add an option to show the caller of a function at each entry of the
function graph tracer, similar to what the function tracer does.
- Abstract out ftrace_regs from being used directly like pt_regs
ftrace_regs was created to store a partial pt_regs. It holds only the
registers and stack information to get to the function arguments and
return values. On several archs, it is simply a wrapper around pt_regs.
But some users would access ftrace_regs directly to get the pt_regs which
will not work on all archs. Make ftrace_regs an abstract structure that
requires all access to its fields be through accessor functions.
- Show how long it takes to do function code modifications
When code modification for function hooks happen, it always had the time
recorded in how long it took to do the conversion. But this value was
never exported. Recently the code was touched due to new ROX modification
handling that caused a large slow down in doing the modifications and
had a significant impact on boot times.
Expose the timings in the dyn_ftrace_total_info file. This file was
created a while ago to show information about memory usage and such to
implement dynamic function tracing. It's also an appropriate file to store
the timings of this modification as well. This will make it easier to see
the impact of changes to code modification on boot up timings.
- Other clean ups and small fixes
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZztrUxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qnnNAQD6w4q9VQ7oOE2qKLqtnj87h4c1GqKn
SPkpEfC3n/ATEAD/fnYjT/eOSlHiGHuD/aTA+U/bETrT99bozGM/4mFKEgY=
=6nCa
-----END PGP SIGNATURE-----
Merge tag 'ftrace-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace updates from Steven Rostedt:
- Restructure the function graph shadow stack to prepare it for use
with kretprobes
With the goal of merging the shadow stack logic of function graph and
kretprobes, some more restructuring of the function shadow stack is
required.
Move out function graph specific fields from the fgraph
infrastructure and store it on the new stack variables that can pass
data from the entry callback to the exit callback.
Hopefully, with this change, the merge of kretprobes to use fgraph
shadow stacks will be ready by the next merge window.
- Make shadow stack 4k instead of using PAGE_SIZE.
Some architectures have very large PAGE_SIZE values which make its
use for shadow stacks waste a lot of memory.
- Give shadow stacks its own kmem cache.
When function graph is started, every task on the system gets a
shadow stack. In the future, shadow stacks may not be 4K in size.
Have it have its own kmem cache so that whatever size it becomes will
still be efficient in allocations.
- Initialize profiler graph ops as it will be needed for new updates to
fgraph
- Convert to use guard(mutex) for several ftrace and fgraph functions
- Add more comments and documentation
- Show function return address in function graph tracer
Add an option to show the caller of a function at each entry of the
function graph tracer, similar to what the function tracer does.
- Abstract out ftrace_regs from being used directly like pt_regs
ftrace_regs was created to store a partial pt_regs. It holds only the
registers and stack information to get to the function arguments and
return values. On several archs, it is simply a wrapper around
pt_regs. But some users would access ftrace_regs directly to get the
pt_regs which will not work on all archs. Make ftrace_regs an
abstract structure that requires all access to its fields be through
accessor functions.
- Show how long it takes to do function code modifications
When code modification for function hooks happen, it always had the
time recorded in how long it took to do the conversion. But this
value was never exported. Recently the code was touched due to new
ROX modification handling that caused a large slow down in doing the
modifications and had a significant impact on boot times.
Expose the timings in the dyn_ftrace_total_info file. This file was
created a while ago to show information about memory usage and such
to implement dynamic function tracing. It's also an appropriate file
to store the timings of this modification as well. This will make it
easier to see the impact of changes to code modification on boot up
timings.
- Other clean ups and small fixes
* tag 'ftrace-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (22 commits)
ftrace: Show timings of how long nop patching took
ftrace: Use guard to take ftrace_lock in ftrace_graph_set_hash()
ftrace: Use guard to take the ftrace_lock in release_probe()
ftrace: Use guard to lock ftrace_lock in cache_mod()
ftrace: Use guard for match_records()
fgraph: Use guard(mutex)(&ftrace_lock) for unregister_ftrace_graph()
fgraph: Give ret_stack its own kmem cache
fgraph: Separate size of ret_stack from PAGE_SIZE
ftrace: Rename ftrace_regs_return_value to ftrace_regs_get_return_value
selftests/ftrace: Fix check of return value in fgraph-retval.tc test
ftrace: Use arch_ftrace_regs() for ftrace_regs_*() macros
ftrace: Consolidate ftrace_regs accessor functions for archs using pt_regs
ftrace: Make ftrace_regs abstract from direct use
fgragh: No need to invoke the function call_filter_check_discard()
fgraph: Simplify return address printing in function graph tracer
function_graph: Remove unnecessary initialization in ftrace_graph_ret_addr()
function_graph: Support recording and printing the function return address
ftrace: Have calltime be saved in the fgraph storage
ftrace: Use a running sleeptime instead of saving on shadow stack
fgraph: Use fgraph data to store subtime for profiler
...
When executing the following command:
# echo "write*:mod:ext3" > /sys/kernel/tracing/stack_trace_filter
The current mod command causes a null pointer dereference. While commit
0f17976568 ("ftrace: Fix regression with module command in stack_trace_filter")
has addressed part of the issue, it left a corner case unhandled, which still
results in a kernel crash.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241120052750.275463-1-guoweikang.kernel@gmail.com
Fixes: 04ec7bb642 ("tracing: Have the trace_array hold the list of registered func probes");
Signed-off-by: guoweikang <guoweikang.kernel@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Uprobes:
- Add BPF session support (Jiri Olsa)
- Switch to RCU Tasks Trace flavor for better performance (Andrii Nakryiko)
- Massively increase uretprobe SMP scalability by SRCU-protecting
the uretprobe lifetime (Andrii Nakryiko)
- Kill xol_area->slot_count (Oleg Nesterov)
- Core facilities:
- Implement targeted high-frequency profiling by adding the ability
for an event to "pause" or "resume" AUX area tracing (Adrian Hunter)
- VM profiling/sampling:
- Correct perf sampling with guest VMs (Colton Lewis)
- New hardware support:
- x86/intel: Add PMU support for Intel ArrowLake-H CPUs (Dapeng Mi)
- Misc fixes and enhancements:
- x86/intel/pt: Fix buffer full but size is 0 case (Adrian Hunter)
- x86/amd: Warn only on new bits set (Breno Leitao)
- x86/amd/uncore: Avoid a false positive warning about snprintf
truncation in amd_uncore_umc_ctx_init (Jean Delvare)
- uprobes: Re-order struct uprobe_task to save some space (Christophe JAILLET)
- x86/rapl: Move the pmu allocation out of CPU hotplug (Kan Liang)
- x86/rapl: Clean up cpumask and hotplug (Kan Liang)
- uprobes: Deuglify xol_get_insn_slot/xol_free_insn_slot paths (Oleg Nesterov)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=ItOT
-----END PGP SIGNATURE-----
Merge tag 'perf-core-2024-11-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull performance events updates from Ingo Molnar:
"Uprobes:
- Add BPF session support (Jiri Olsa)
- Switch to RCU Tasks Trace flavor for better performance (Andrii
Nakryiko)
- Massively increase uretprobe SMP scalability by SRCU-protecting
the uretprobe lifetime (Andrii Nakryiko)
- Kill xol_area->slot_count (Oleg Nesterov)
Core facilities:
- Implement targeted high-frequency profiling by adding the ability
for an event to "pause" or "resume" AUX area tracing (Adrian
Hunter)
VM profiling/sampling:
- Correct perf sampling with guest VMs (Colton Lewis)
New hardware support:
- x86/intel: Add PMU support for Intel ArrowLake-H CPUs (Dapeng Mi)
Misc fixes and enhancements:
- x86/intel/pt: Fix buffer full but size is 0 case (Adrian Hunter)
- x86/amd: Warn only on new bits set (Breno Leitao)
- x86/amd/uncore: Avoid a false positive warning about snprintf
truncation in amd_uncore_umc_ctx_init (Jean Delvare)
- uprobes: Re-order struct uprobe_task to save some space
(Christophe JAILLET)
- x86/rapl: Move the pmu allocation out of CPU hotplug (Kan Liang)
- x86/rapl: Clean up cpumask and hotplug (Kan Liang)
- uprobes: Deuglify xol_get_insn_slot/xol_free_insn_slot paths (Oleg
Nesterov)"
* tag 'perf-core-2024-11-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
perf/core: Correct perf sampling with guest VMs
perf/x86: Refactor misc flag assignments
perf/powerpc: Use perf_arch_instruction_pointer()
perf/core: Hoist perf_instruction_pointer() and perf_misc_flags()
perf/arm: Drop unused functions
uprobes: Re-order struct uprobe_task to save some space
perf/x86/amd/uncore: Avoid a false positive warning about snprintf truncation in amd_uncore_umc_ctx_init
perf/x86/intel: Do not enable large PEBS for events with aux actions or aux sampling
perf/x86/intel/pt: Add support for pause / resume
perf/core: Add aux_pause, aux_resume, aux_start_paused
perf/x86/intel/pt: Fix buffer full but size is 0 case
uprobes: SRCU-protect uretprobe lifetime (with timeout)
uprobes: allow put_uprobe() from non-sleepable softirq context
perf/x86/rapl: Clean up cpumask and hotplug
perf/x86/rapl: Move the pmu allocation out of CPU hotplug
uprobe: Add support for session consumer
uprobe: Add data pointer to consumer handlers
perf/x86/amd: Warn only on new bits set
uprobes: fold xol_take_insn_slot() into xol_get_insn_slot()
uprobes: kill xol_area->slot_count
...
Currently, space for raw sample data is always allocated within sample
records for both BPF output and tracepoint events. This leads to unused
space in sample records when raw sample data is not requested.
This patch enforces checking sample type of an event in
perf_sample_save_raw_data(). So raw sample data will only be saved if
explicitly requested, reducing overhead when it is not needed.
Fixes: 0a9081cf0a ("perf/core: Add perf_sample_save_raw_data() helper")
Signed-off-by: Yabin Cui <yabinc@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240515193610.2350456-2-yabinc@google.com
The issue that unrelated function name is shown on stack trace like
following even though it should be trampoline code address is caused by
the creation of trampoline code in the area where .init.text section
of module was freed after module is loaded.
bash-1344 [002] ..... 43.644608: <stack trace>
=> (MODULE INIT FUNCTION)
=> vfs_write
=> ksys_write
=> do_syscall_64
=> entry_SYSCALL_64_after_hwframe
To resolve this, when function address of stack trace entry is in
trampoline, output without looking up symbol name.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241021071454.34610-2-tatsuya.s2862@gmail.com
Signed-off-by: Tatsuya S <tatsuya.s2862@gmail.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Revert: "ring-buffer: Do not have boot mapped buffers hook to CPU hotplug"
A crash that happened on cpu hotplug was actually caused by the incorrect
ref counting that was fixed by commit 2cf9733891 ("ring-buffer: Fix
refcount setting of boot mapped buffers"). The removal of calling cpu
hotplug callbacks on memory mapped buffers was not an issue even though
the tests at the time pointed toward it. But in fact, there's a check in
that code that tests to see if the buffers are already allocated or not,
and will not allocate them again if they are. Not calling the cpu hotplug
callbacks ended up not initializing the non boot CPU buffers.
Simply remove that change.
- Clear all CPU buffers when starting tracing in a boot mapped buffer
To properly process events from a previous boot, the address space needs to
be accounted for due to KASLR and the events in the buffer are updated
accordingly when read. This also requires that when the buffer has tracing
enabled again in the current boot that the buffers are reset so that events
from the previous boot do not interact with the events of the current boot
and cause confusing due to not having the proper meta data.
It was found that if a CPU is taken offline, that its per CPU buffer is not
reset when tracing starts. This allows for events to be from both the
previous boot and the current boot to be in the buffer at the same time.
Clear all CPU buffers when tracing is started in a boot mapped buffer.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZzdr5hQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qq3gAQDsqNNld3D3wW72VMJ52d9zdBXFUdrV
hbszve+PSj/wuAD/TeCp0BcI8Az+G7/enMXnlEugLo3XKLr/YvPQ3nlb8QA=
=VR4z
-----END PGP SIGNATURE-----
Merge tag 'trace-ringbuffer-v6.12-rc7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ring buffer fixes from Steven Rostedt:
- Revert: "ring-buffer: Do not have boot mapped buffers hook to CPU
hotplug"
A crash that happened on cpu hotplug was actually caused by the
incorrect ref counting that was fixed by commit 2cf9733891
("ring-buffer: Fix refcount setting of boot mapped buffers"). The
removal of calling cpu hotplug callbacks on memory mapped buffers was
not an issue even though the tests at the time pointed toward it. But
in fact, there's a check in that code that tests to see if the
buffers are already allocated or not, and will not allocate them
again if they are. Not calling the cpu hotplug callbacks ended up not
initializing the non boot CPU buffers.
Simply remove that change.
- Clear all CPU buffers when starting tracing in a boot mapped buffer
To properly process events from a previous boot, the address space
needs to be accounted for due to KASLR and the events in the buffer
are updated accordingly when read. This also requires that when the
buffer has tracing enabled again in the current boot that the buffers
are reset so that events from the previous boot do not interact with
the events of the current boot and cause confusing due to not having
the proper meta data.
It was found that if a CPU is taken offline, that its per CPU buffer
is not reset when tracing starts. This allows for events to be from
both the previous boot and the current boot to be in the buffer at
the same time. Clear all CPU buffers when tracing is started in a
boot mapped buffer.
* tag 'trace-ringbuffer-v6.12-rc7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/ring-buffer: Clear all memory mapped CPU ring buffers on first recording
Revert: "ring-buffer: Do not have boot mapped buffers hook to CPU hotplug"
The events of a memory mapped ring buffer from the previous boot should
not be mixed in with events from the current boot. There's meta data that
is used to handle KASLR so that function names can be shown properly.
Also, since the timestamps of the previous boot have no meaning to the
timestamps of the current boot, having them intermingled in a buffer can
also cause confusion because there could possibly be events in the future.
When a trace is activated the meta data is reset so that the pointers of
are now processed for the new address space. The trace buffers are reset
when tracing starts for the first time. The problem here is that the reset
only happens on online CPUs. If a CPU is offline, it does not get reset.
To demonstrate the issue, a previous boot had tracing enabled in the boot
mapped ring buffer on reboot. On the following boot, tracing has not been
started yet so the function trace from the previous boot is still visible.
# trace-cmd show -B boot_mapped -c 3 | tail
<idle>-0 [003] d.h2. 156.462395: __rcu_read_lock <-cpu_emergency_disable_virtualization
<idle>-0 [003] d.h2. 156.462396: vmx_emergency_disable_virtualization_cpu <-cpu_emergency_disable_virtualization
<idle>-0 [003] d.h2. 156.462396: __rcu_read_unlock <-__sysvec_reboot
<idle>-0 [003] d.h2. 156.462397: stop_this_cpu <-__sysvec_reboot
<idle>-0 [003] d.h2. 156.462397: set_cpu_online <-stop_this_cpu
<idle>-0 [003] d.h2. 156.462397: disable_local_APIC <-stop_this_cpu
<idle>-0 [003] d.h2. 156.462398: clear_local_APIC <-disable_local_APIC
<idle>-0 [003] d.h2. 156.462574: mcheck_cpu_clear <-stop_this_cpu
<idle>-0 [003] d.h2. 156.462575: mce_intel_feature_clear <-stop_this_cpu
<idle>-0 [003] d.h2. 156.462575: lmce_supported <-mce_intel_feature_clear
Now, if CPU 3 is taken offline, and tracing is started on the memory
mapped ring buffer, the events from the previous boot in the CPU 3 ring
buffer is not reset. Now those events are using the meta data from the
current boot and produces just hex values.
# echo 0 > /sys/devices/system/cpu/cpu3/online
# trace-cmd start -B boot_mapped -p function
# trace-cmd show -B boot_mapped -c 3 | tail
<idle>-0 [003] d.h2. 156.462395: 0xffffffff9a1e3194 <-0xffffffff9a0f655e
<idle>-0 [003] d.h2. 156.462396: 0xffffffff9a0a1d24 <-0xffffffff9a0f656f
<idle>-0 [003] d.h2. 156.462396: 0xffffffff9a1e6bc4 <-0xffffffff9a0f7323
<idle>-0 [003] d.h2. 156.462397: 0xffffffff9a0d12b4 <-0xffffffff9a0f732a
<idle>-0 [003] d.h2. 156.462397: 0xffffffff9a1458d4 <-0xffffffff9a0d12e2
<idle>-0 [003] d.h2. 156.462397: 0xffffffff9a0faed4 <-0xffffffff9a0d12e7
<idle>-0 [003] d.h2. 156.462398: 0xffffffff9a0faaf4 <-0xffffffff9a0faef2
<idle>-0 [003] d.h2. 156.462574: 0xffffffff9a0e3444 <-0xffffffff9a0d12ef
<idle>-0 [003] d.h2. 156.462575: 0xffffffff9a0e4964 <-0xffffffff9a0d12ef
<idle>-0 [003] d.h2. 156.462575: 0xffffffff9a0e3fb0 <-0xffffffff9a0e496f
Reset all CPUs when starting a boot mapped ring buffer for the first time,
and not just the online CPUs.
Fixes: 7a1d1e4b96 ("tracing/ring-buffer: Add last_boot_info file to boot instance")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
A crash happened when testing cpu hotplug with respect to the memory
mapped ring buffers. It was assumed that the hot plug code was adding a
per CPU buffer that was already created that caused the crash. The real
problem was due to ref counting and was fixed by commit 2cf9733891
("ring-buffer: Fix refcount setting of boot mapped buffers").
When a per CPU buffer is created, it will not be created again even with
CPU hotplug, so the fix to not use CPU hotplug was a red herring. In fact,
it caused only the boot CPU buffer to be created, leaving the other CPU
per CPU buffers disabled.
Revert that change as it was not the culprit of the fix it was intended to
be.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241113230839.6c03640f@gandalf.local.home
Fixes: 912da2c384 ("ring-buffer: Do not have boot mapped buffers hook to CPU hotplug")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Cross-merge bpf fixes after downstream PR.
In particular to bring the fix in
commit aa30eb3260 ("bpf: Force checkpoint when jmp history is too long").
The follow up verifier work depends on it.
And the fix in
commit 6801cf7890 ("selftests/bpf: Use -4095 as the bad address for bits iterator").
It's fixing instability of BPF CI on s390 arch.
No conflicts.
Adjacent changes in:
Auto-merging arch/Kconfig
Auto-merging kernel/bpf/helpers.c
Auto-merging kernel/bpf/memalloc.c
Auto-merging kernel/bpf/verifier.c
Auto-merging mm/slab_common.c
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The check on field->field being true is handled as the first check
on the cascaded if statement, so the later checks on field->field
are redundant because this clause has already been handled. Since
this later check is redundant, just remove it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241107120530.18728-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Placing bpf_session_run_ctx layer in between bpf_run_ctx and
bpf_uprobe_multi_run_ctx, so the session data can be retrieved
from uprobe_multi link.
Plus granting session kfuncs access to uprobe session programs.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-5-jolsa@kernel.org
Adding support to attach BPF program for entry and return probe
of the same function. This is common use case which at the moment
requires to create two uprobe multi links.
Adding new BPF_TRACE_UPROBE_SESSION attach type that instructs
kernel to attach single link program to both entry and exit probe.
It's possible to control execution of the BPF program on return
probe simply by returning zero or non zero from the entry BPF
program execution to execute or not the BPF program on return
probe respectively.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-4-jolsa@kernel.org
As suggested by Andrii make uprobe multi bpf programs to always return 0,
so they can't force uprobe removal.
Keeping the int return type for uprobe_prog_run, because it will be used
in following session changes.
Fixes: 89ae89f53d ("bpf: Add multi uprobe link")
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-3-jolsa@kernel.org
The function simple_strtoul performs no error checking in scenarios
where the input value overflows the intended output variable.
This results in this function successfully returning, even when the
output does not match the input string (aka the function returns
successfully even when the result is wrong).
Or as it was mentioned [1], "...simple_strtol(), simple_strtoll(),
simple_strtoul(), and simple_strtoull() functions explicitly ignore
overflows, which may lead to unexpected results in callers."
Hence, the use of those functions is discouraged.
This patch replaces all uses of the simple_strtoul with the safer
alternatives kstrtoint and kstrtol.
[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#simple-strtol-simple-strtoll-simple-strtoul-simple-strtoull
Signed-off-by: Yuran Pereira <yuran.pereira@hotmail.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
[nir: style fixes]
Signed-off-by: Nir Lichtman <nir@lichtman.org>
Link: https://lore.kernel.org/r/20241028192100.GB918454@lichtman.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
It was possible to enable tracing with no IRQ tracing support. The
tracing infrastructure would then record TRACE_FLAG_IRQS_NOSUPPORT as
the only tracing flag and show an 'X' in the output.
The last user of this feature was PPC32 which managed to implement it
during PowerPC merge in 2009. Since then, it was unused and the PPC32
dependency was finally removed in commit 0ea5ee0351 ("tracing: Remove
PPC32 wart from config TRACING_SUPPORT").
Since the PowerPC merge the code behind !CONFIG_TRACE_IRQFLAGS_SUPPORT
with TRACING enabled can no longer be selected used and the 'X' is not
displayed or recorded.
Remove the CONFIG_TRACE_IRQFLAGS_SUPPORT from the tracing code. Remove
TRACE_FLAG_IRQS_NOSUPPORT.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241022110112.XJI8I9T2@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Commit ee7f366699 ("tracefs: Have new files inherit the ownership of
their parent") and commit 48b27b6b51 ("tracefs: Set all files to the
same group ownership as the mount option") introduced a new gid mount
option that allows specifying a group to apply to all entries in tracefs.
Document this in the tracing readme.
Cc: Eric Sandeen <sandeen@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Ali Zahraee <ahzahraee@gmail.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/20241030171928.4168869-3-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
strncpy() is deprecated for use on NUL-terminated destination strings [1] and
as such we should prefer more robust and less ambiguous string interfaces.
String copy operations involving manual pointer offset and length
calculations followed by explicit NUL-byte assignments are best changed
to either strscpy or memcpy.
strscpy is not a drop-in replacement as @len would need a one subtracted
from it to avoid truncating the source string.
To not sabotage readability of the current code, use memcpy (retaining
the manual NUL assignment) as this unambiguously describes the desired
behavior.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://github.com/KSPP/linux/issues/90 [2]
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: linux-hardening@vger.kernel.org
Link: https://lore.kernel.org/20241014-strncpy-kernel-trace-trace_events_filter-c-v2-1-d821e81e371e@google.com
Reviewed-by: Kees Cook <kees@kernel.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Previously the size of "struct ftrace_stacks" depended upon PAGE_SIZE.
For the common 4K page size, on a 64-bit system, sizeof(struct
ftrace_stacks) was 32K. But for a 64K page size, sizeof(struct
ftrace_stacks) was 512K.
But ftrace stack usage requirements should be invariant to page size. So
let's redefine FTRACE_KSTACK_ENTRIES so that "struct ftrace_stacks" is
always sized at 32K for 64-bit and 16K for 32-bit.
As a side effect, it removes the PAGE_SIZE compile-time constant
assumption from this code, which is required to reach the goal of
boot-time page size selection.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241021141832.3668264-1-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Since the beginning of ftrace, the code that did the patching had its
timings saved on how long it took to complete. But this information was
never exposed. It was used for debugging and exposing it was always
something that was on the TODO list. Now it's time to expose it. There's
even a file that is where it should go!
Also include how long patching modules took as a separate value.
# cat /sys/kernel/tracing/dyn_ftrace_total_info
57680 pages:231 groups: 9
ftrace boot update time = 14024666 (ns)
ftrace module total update time = 126070 (ns)
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241017113105.1edfa943@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ftrace_lock is taken for most of the ftrace_graph_set_hash() function
throughout the end. Use guard to take the ftrace_lock to simplify the exit
paths.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241028071308.406073025@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ftrace_lock is held throughout the entire release_probe() function.
Use guard to simplify any exit paths.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241028071308.250787901@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ftrace_lock is held throughout cache_mod(), use guard to simplify the
error paths.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241028071308.088458856@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ftrace_lock is held for most of match_records() until the end of the
function. Use guard to make error paths simpler.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241028071307.927146604@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ftrace_lock is held throughout unregister_ftrace_graph(), use a guard
to simplify the error paths.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20241028071307.770550792@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ret_stack (shadow stack used by function graph infrastructure) is
created for every task on the system when function graph is enabled. Give
it its own kmem_cache. This will make it easier to see how much memory is
being used specifically for function graph shadow stacks.
In the future, this size may change and may not be a power of two. Having
its own cache can also keep it from fragmenting memory.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Link: https://lore.kernel.org/20241026063210.7d4910a7@rorschach.local.home
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ret_stack (shadow stack used by function graph infrastructure) is
currently defined as PAGE_SIZE. But some architectures which have 64K
PAGE_SIZE, this is way overkill. Also there's an effort to allow the
PAGE_SIZE to be defined at boot up.
Hard code it for now to 4096. In the future, this size may change and even
be dependent on specific architectures.
Link: https://lore.kernel.org/all/e5067bb8-0fcd-4739-9bca-0e872037d5a1@arm.com/
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241019152951.053f9646@rorschach.local.home
Suggested-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Fix missing mutex unlock in error path of register_ftrace_graph()
A previous fix added a return on an error path and forgot to unlock the
mutex. Instead of dealing with error paths, use guard(mutex) as the mutex
is just released at the exit of the function anyway. Other functions
in this file should be updated with this, but that's a cleanup and not
a fix.
- Change cpuhp setup name to be consistent with other cpuhp states
The same fix that the above patch fixes added a cpuhp_setup_state() call
with the name of "fgraph_idle_init". I was informed that it should instead
be something like: "fgraph:online". Update that too.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZxydTRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qsE/APoDcsqqaDJvQ0OsMqVaPdHoj2IUkU4M
yueb6U/Kyq1m4wEA259W1PZuQlM0Vo0yJM1w2YIAH18UpO09ZroLnbWoUAc=
=2sS+
-----END PGP SIGNATURE-----
Merge tag 'ftrace-v6.12-rc4' into trace/ftrace/core
In order to modify the code that allocates the shadow stacks, merge the
changes that fixed the CPU hotplug shadow stack allocations and build on
top of that.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Fix missing mutex unlock in error path of register_ftrace_graph()
A previous fix added a return on an error path and forgot to unlock the
mutex. Instead of dealing with error paths, use guard(mutex) as the mutex
is just released at the exit of the function anyway. Other functions
in this file should be updated with this, but that's a cleanup and not
a fix.
- Change cpuhp setup name to be consistent with other cpuhp states
The same fix that the above patch fixes added a cpuhp_setup_state() call
with the name of "fgraph_idle_init". I was informed that it should instead
be something like: "fgraph:online". Update that too.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZxydTRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qsE/APoDcsqqaDJvQ0OsMqVaPdHoj2IUkU4M
yueb6U/Kyq1m4wEA259W1PZuQlM0Vo0yJM1w2YIAH18UpO09ZroLnbWoUAc=
=2sS+
-----END PGP SIGNATURE-----
Merge tag 'ftrace-v6.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace fixes from Steven Rostedt:
- Fix missing mutex unlock in error path of register_ftrace_graph()
A previous fix added a return on an error path and forgot to unlock
the mutex. Instead of dealing with error paths, use guard(mutex) as
the mutex is just released at the exit of the function anyway. Other
functions in this file should be updated with this, but that's a
cleanup and not a fix.
- Change cpuhp setup name to be consistent with other cpuhp states
The same fix that the above patch fixes added a cpuhp_setup_state()
call with the name of "fgraph_idle_init". I was informed that it
should instead be something like: "fgraph:online". Update that too.
* tag 'ftrace-v6.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
fgraph: Change the name of cpuhp state to "fgraph:online"
fgraph: Fix missing unlock in register_ftrace_graph()
The cpuhp state name given to cpuhp_setup_state() is "fgraph_idle_init"
which doesn't really conform to the names that are used for cpu hotplug
setups. Instead rename it to "fgraph:online" to be in line with other
states.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/20241024222944.473d88c5@rorschach.local.home
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 2c02f7375e ("fgraph: Use CPU hotplug mechanism to initialize idle shadow stacks")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Use guard(mutex)() to acquire and automatically release ftrace_lock,
fixing the issue of not unlocking when calling cpuhp_setup_state()
fails.
Fixes smatch warning:
kernel/trace/fgraph.c:1317 register_ftrace_graph() warn: inconsistent returns '&ftrace_lock'.
Link: https://lore.kernel.org/20241024155917.1019580-1-lihuafei1@huawei.com
Fixes: 2c02f7375e ("fgraph: Use CPU hotplug mechanism to initialize idle shadow stacks")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202410220121.wxg0olfd-lkp@intel.com/
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Fix an out-of-bounds read in bpf_link_show_fdinfo for BPF
sockmap link file descriptors (Hou Tao)
- Fix BPF arm64 JIT's address emission with tag-based KASAN
enabled reserving not enough size (Peter Collingbourne)
- Fix BPF verifier do_misc_fixups patching for inlining of the
bpf_get_branch_snapshot BPF helper (Andrii Nakryiko)
- Fix a BPF verifier bug and reject BPF program write attempts
into read-only marked BPF maps (Daniel Borkmann)
- Fix perf_event_detach_bpf_prog error handling by removing an
invalid check which would skip BPF program release (Jiri Olsa)
- Fix memory leak when parsing mount options for the BPF
filesystem (Hou Tao)
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
-----BEGIN PGP SIGNATURE-----
iIsEABYIADMWIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZxrAzxUcZGFuaWVsQGlv
Z2VhcmJveC5uZXQACgkQ2yufC7HISIPcHwD8DnBSPlHX9OezMWCm8mjVx2Fd26W9
/IaiW2tyOPtoSGIA/3hfgfLrxkb3Raoh0miQB2+FRrz9e+y7i8c4Q91mcUgJ
=Hvht
-----END PGP SIGNATURE-----
Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Daniel Borkmann:
- Fix an out-of-bounds read in bpf_link_show_fdinfo for BPF sockmap
link file descriptors (Hou Tao)
- Fix BPF arm64 JIT's address emission with tag-based KASAN enabled
reserving not enough size (Peter Collingbourne)
- Fix BPF verifier do_misc_fixups patching for inlining of the
bpf_get_branch_snapshot BPF helper (Andrii Nakryiko)
- Fix a BPF verifier bug and reject BPF program write attempts into
read-only marked BPF maps (Daniel Borkmann)
- Fix perf_event_detach_bpf_prog error handling by removing an invalid
check which would skip BPF program release (Jiri Olsa)
- Fix memory leak when parsing mount options for the BPF filesystem
(Hou Tao)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf: Check validity of link->type in bpf_link_show_fdinfo()
bpf: Add the missing BPF_LINK_TYPE invocation for sockmap
bpf: fix do_misc_fixups() for bpf_get_branch_snapshot()
bpf,perf: Fix perf_event_detach_bpf_prog error handling
selftests/bpf: Add test for passing in uninit mtu_len
selftests/bpf: Add test for writes to .rodata
bpf: Remove MEM_UNINIT from skb/xdp MTU helpers
bpf: Fix overloading of MEM_UNINIT's meaning
bpf: Add MEM_WRITE attribute
bpf: Preserve param->string when parsing mount options
bpf, arm64: Fix address emission with tag-based KASAN enabled
Peter reported that perf_event_detach_bpf_prog might skip to release
the bpf program for -ENOENT error from bpf_prog_array_copy.
This can't happen because bpf program is stored in perf event and is
detached and released only when perf event is freed.
Let's drop the -ENOENT check and make sure the bpf program is released
in any case.
Fixes: 170a7e3ea0 ("bpf: bpf_prog_array_copy() should return -ENOENT if exclude_prog not found")
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241023200352.3488610-1-jolsa@kernel.org
Closes: https://lore.kernel.org/lkml/20241022111638.GC16066@noisy.programming.kicks-ass.net/
Adding data pointer to both entry and exit consumer handlers and all
its users. The functionality itself is coming in following change.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241018202252.693462-2-jolsa@kernel.org
strlen() returns a string length excluding the null byte. If the string
length equals to the maximum buffer length, the buffer will have no
space for the NULL terminating character.
This commit checks this condition and returns failure for it.
Link: https://lore.kernel.org/all/20241007144724.920954-1-leo.yan@arm.com/
Fixes: dec65d79fd ("tracing/probe: Check event name length correctly")
Signed-off-by: Leo Yan <leo.yan@arm.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
When creating a trace_probe we would set nr_args prior to truncating the
arguments to MAX_TRACE_ARGS. However, we would only initialize arguments
up to the limit.
This caused invalid memory access when attempting to set up probes with
more than 128 fetchargs.
BUG: kernel NULL pointer dereference, address: 0000000000000020
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 0 UID: 0 PID: 1769 Comm: cat Not tainted 6.11.0-rc7+ #8
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014
RIP: 0010:__set_print_fmt+0x134/0x330
Resolve the issue by applying the MAX_TRACE_ARGS limit earlier. Return
an error when there are too many arguments instead of silently
truncating.
Link: https://lore.kernel.org/all/20240930202656.292869-1-mikel@mikelr.com/
Fixes: 035ba76014 ("tracing/probes: cleanup: Set trace_probe::nr_args at trace_probe_init")
Signed-off-by: Mikel Rychliski <mikel@mikelr.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Add a MEM_WRITE attribute for BPF helper functions which can be used in
bpf_func_proto to annotate an argument type in order to let the verifier
know that the helper writes into the memory passed as an argument. In
the past MEM_UNINIT has been (ab)used for this function, but the latter
merely tells the verifier that the passed memory can be uninitialized.
There have been bugs with overloading the latter but aside from that
there are also cases where the passed memory is read + written which
currently cannot be expressed, see also 4b3786a6c5 ("bpf: Zero former
ARG_PTR_TO_{LONG,INT} args in case of error").
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20241021152809.33343-1-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Implement bpf_send_signal_task kfunc that is similar to
bpf_send_signal_thread and bpf_send_signal helpers but can be used to
send signals to other threads and processes. It also supports sending a
cookie with the signal similar to sigqueue().
If the receiving process establishes a handler for the signal using the
SA_SIGINFO flag to sigaction(), then it can obtain this cookie via the
si_value field of the siginfo_t structure passed as the second argument
to the handler.
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241016084136.10305-2-puranjay@kernel.org
- Fix another aspect of delayed dequeued tasks wrt determining their state,
i.e., whether they're runnable or blocked
- Handle delayed dequeued tasks and their migration wrt PSI properly
- Fix the situation where a delayed dequeue task gets enqueued into a new
class, which should not happen
- Fix a case where memory allocation would happen while the runqueue lock is
held, which is a no-no
- Do not over-schedule when tasks with shorter slices preempt the currently
running task
- Make sure delayed to deque entities are properly handled before unthrottling
- Other smaller cleanups and improvements
-----BEGIN PGP SIGNATURE-----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=1D7H
-----END PGP SIGNATURE-----
Merge tag 'sched_urgent_for_v6.12_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduling fixes from Borislav Petkov:
- Add PREEMPT_RT maintainers
- Fix another aspect of delayed dequeued tasks wrt determining their
state, i.e., whether they're runnable or blocked
- Handle delayed dequeued tasks and their migration wrt PSI properly
- Fix the situation where a delayed dequeue task gets enqueued into a
new class, which should not happen
- Fix a case where memory allocation would happen while the runqueue
lock is held, which is a no-no
- Do not over-schedule when tasks with shorter slices preempt the
currently running task
- Make sure delayed to deque entities are properly handled before
unthrottling
- Other smaller cleanups and improvements
* tag 'sched_urgent_for_v6.12_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
MAINTAINERS: Add an entry for PREEMPT_RT.
sched/fair: Fix external p->on_rq users
sched/psi: Fix mistaken CPU pressure indication after corrupted task state bug
sched/core: Dequeue PSI signals for blocked tasks that are delayed
sched: Fix delayed_dequeue vs switched_from_fair()
sched/core: Disable page allocation in task_tick_mm_cid()
sched/deadline: Use hrtick_enabled_dl() before start_hrtick_dl()
sched/eevdf: Fix wakeup-preempt by checking cfs_rq->nr_running
sched: Fix sched_delayed vs cfs_bandwidth
- Fix allocation of idle shadow stack allocation during hotplug
If function graph tracing is started when a CPU is offline, if it were
come online during the trace then the idle task that represents the CPU
will not get a shadow stack allocated for it. This means all function
graph hooks that happen while that idle task is running (including in
interrupt mode) will have all its events dropped.
Switch over to the CPU hotplug mechanism that will have any newly
brought on line CPU get a callback that can allocate the shadow stack
for its idle task.
- Fix allocation size of the ret_stack_list array
When function graph tracing converted over to allowing more than one
user at a time, it had to convert its shadow stack from an array of
ret_stack structures to an array of unsigned longs. The shadow stacks
are allocated in batches of 32 at a time and assigned to every running
task. The batch is held by the ret_stack_list array. But when the
conversion happened, instead of allocating an array of 32 pointers, it
was allocated as a ret_stack itself (PAGE_SIZE). This ret_stack_list
gets passed to a function that iterates over what it believes is its
size defined by the FTRACE_RETSTACK_ALLOC_SIZE macro (which is 32).
Luckily (PAGE_SIZE) is greater than 32 * sizeof(long), otherwise this
would have been an array overflow. This still should be fixed and the
ret_stack_list should be allocated to the size it is expected to be as
someday it may end up being bigger than SHADOW_STACK_SIZE.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZxP8RhQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qmW3AP4qCOvU/g9g6u32gIZmS1oUWqe3q+Rq
9OKCk0JP6GGc8AD/cF816lbs5vpDiZFdbBvaz5gLHqhfAt35NVU8T5tbJA4=
=Lh3A
-----END PGP SIGNATURE-----
Merge tag 'ftrace-v6.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace fixes from Steven Rostedt:
"A couple of fixes to function graph infrastructure:
- Fix allocation of idle shadow stack allocation during hotplug
If function graph tracing is started when a CPU is offline, if it
were come online during the trace then the idle task that
represents the CPU will not get a shadow stack allocated for it.
This means all function graph hooks that happen while that idle
task is running (including in interrupt mode) will have all its
events dropped.
Switch over to the CPU hotplug mechanism that will have any newly
brought on line CPU get a callback that can allocate the shadow
stack for its idle task.
- Fix allocation size of the ret_stack_list array
When function graph tracing converted over to allowing more than
one user at a time, it had to convert its shadow stack from an
array of ret_stack structures to an array of unsigned longs. The
shadow stacks are allocated in batches of 32 at a time and assigned
to every running task. The batch is held by the ret_stack_list
array.
But when the conversion happened, instead of allocating an array of
32 pointers, it was allocated as a ret_stack itself (PAGE_SIZE).
This ret_stack_list gets passed to a function that iterates over
what it believes is its size defined by the
FTRACE_RETSTACK_ALLOC_SIZE macro (which is 32).
Luckily (PAGE_SIZE) is greater than 32 * sizeof(long), otherwise
this would have been an array overflow. This still should be fixed
and the ret_stack_list should be allocated to the size it is
expected to be as someday it may end up being bigger than
SHADOW_STACK_SIZE"
* tag 'ftrace-v6.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
fgraph: Allocate ret_stack_list with proper size
fgraph: Use CPU hotplug mechanism to initialize idle shadow stacks
Reorganize kerneldoc parameter names to match the parameter
order in the function header.
Problems identified using Coccinelle.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20240930112121.95324-22-Julia.Lawall@inria.fr
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function rb_check_pages() validates the integrity of a specified
per-CPU tracing ring buffer. It does so by traversing the underlying
linked list and checking its next and prev links.
To guarantee that the list isn't modified during the check, a caller
typically needs to take cpu_buffer->reader_lock. This prevents the check
from running concurrently, for example, with a potential reader which
can make the list temporarily inconsistent when swapping its old reader
page into the buffer.
A problem with this approach is that the time when interrupts are
disabled is non-deterministic, dependent on the ring buffer size. This
particularly affects PREEMPT_RT because the reader_lock is a raw
spinlock which doesn't become sleepable on PREEMPT_RT kernels.
Modify the check so it still attempts to traverse the entire list, but
gives up the reader_lock between checking individual pages. Introduce
for this purpose a new variable ring_buffer_per_cpu.cnt which is bumped
any time the list is modified. The value is used by rb_check_pages() to
detect such a change and restart the check.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241015112810.27203-1-petr.pavlu@suse.com
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ret_stack_list is an array of ret_stack shadow stacks for the function
graph usage. When the first function graph is enabled, all tasks in the
system get a shadow stack. The ret_stack_list is a 32 element array of
pointers to these shadow stacks. It allocates the shadow stack in batches
(32 stacks at a time), assigns them to running tasks, and continues until
all tasks are covered.
When the function graph shadow stack changed from an array of
ftrace_ret_stack structures to an array of longs, the allocation of
ret_stack_list went from allocating an array of 32 elements to just a
block defined by SHADOW_STACK_SIZE. Luckily, that's defined as PAGE_SIZE
and is much more than enough to hold 32 pointers. But it is way overkill
for the amount needed to allocate.
Change the allocation of ret_stack_list back to a kcalloc() of
FTRACE_RETSTACK_ALLOC_SIZE pointers.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241018215212.23f13f40@rorschach
Fixes: 42675b723b ("function_graph: Convert ret_stack to a series of longs")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function graph infrastructure allocates a shadow stack for every task
when enabled. This includes the idle tasks. The first time the function
graph is invoked, the shadow stacks are created and never freed until the
task exits. This includes the idle tasks.
Only the idle tasks that were for online CPUs had their shadow stacks
created when function graph tracing started. If function graph tracing is
enabled and a CPU comes online, the idle task representing that CPU will
not have its shadow stack created, and all function graph tracing for that
idle task will be silently dropped.
Instead, use the CPU hotplug mechanism to allocate the idle shadow stacks.
This will include idle tasks for CPUs that come online during tracing.
This issue can be reproduced by:
# cd /sys/kernel/tracing
# echo 0 > /sys/devices/system/cpu/cpu1/online
# echo 0 > set_ftrace_pid
# echo function_graph > current_tracer
# echo 1 > options/funcgraph-proc
# echo 1 > /sys/devices/system/cpu/cpu1
# grep '<idle>' per_cpu/cpu1/trace | head
Before, nothing would show up.
After:
1) <idle>-0 | 0.811 us | __enqueue_entity();
1) <idle>-0 | 5.626 us | } /* enqueue_entity */
1) <idle>-0 | | dl_server_update_idle_time() {
1) <idle>-0 | | dl_scaled_delta_exec() {
1) <idle>-0 | 0.450 us | arch_scale_cpu_capacity();
1) <idle>-0 | 1.242 us | }
1) <idle>-0 | 1.908 us | }
1) <idle>-0 | | dl_server_start() {
1) <idle>-0 | | enqueue_dl_entity() {
1) <idle>-0 | | task_contending() {
Note, if tracing stops and restarts, the old way would then initialize
the onlined CPUs.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/20241018214300.6df82178@rorschach
Fixes: 868baf07b1 ("ftrace: Fix memory leak with function graph and cpu hotplug")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
- Fix BPF verifier to not affect subreg_def marks in its range
propagation, from Eduard Zingerman.
- Fix a truncation bug in the BPF verifier's handling of
coerce_reg_to_size_sx, from Dimitar Kanaliev.
- Fix the BPF verifier's delta propagation between linked
registers under 32-bit addition, from Daniel Borkmann.
- Fix a NULL pointer dereference in BPF devmap due to missing
rxq information, from Florian Kauer.
- Fix a memory leak in bpf_core_apply, from Jiri Olsa.
- Fix an UBSAN-reported array-index-out-of-bounds in BTF
parsing for arrays of nested structs, from Hou Tao.
- Fix build ID fetching where memory areas backing the file
were created with memfd_secret, from Andrii Nakryiko.
- Fix BPF task iterator tid filtering which was incorrectly
using pid instead of tid, from Jordan Rome.
- Several fixes for BPF sockmap and BPF sockhash redirection
in combination with vsocks, from Michal Luczaj.
- Fix riscv BPF JIT and make BPF_CMPXCHG fully ordered,
from Andrea Parri.
- Fix riscv BPF JIT under CONFIG_CFI_CLANG to prevent the
possibility of an infinite BPF tailcall, from Pu Lehui.
- Fix a build warning from resolve_btfids that bpf_lsm_key_free
cannot be resolved, from Thomas Weißschuh.
- Fix a bug in kfunc BTF caching for modules where the wrong
BTF object was returned, from Toke Høiland-Jørgensen.
- Fix a BPF selftest compilation error in cgroup-related tests
with musl libc, from Tony Ambardar.
- Several fixes to BPF link info dumps to fill missing fields,
from Tyrone Wu.
- Add BPF selftests for kfuncs from multiple modules, checking
that the correct kfuncs are called, from Simon Sundberg.
- Ensure that internal and user-facing bpf_redirect flags
don't overlap, also from Toke Høiland-Jørgensen.
- Switch to use kvzmalloc to allocate BPF verifier environment,
from Rik van Riel.
- Use raw_spinlock_t in BPF ringbuf to fix a sleep in atomic
splat under RT, from Wander Lairson Costa.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
-----BEGIN PGP SIGNATURE-----
iIsEABYIADMWIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZxK4OhUcZGFuaWVsQGlv
Z2VhcmJveC5uZXQACgkQ2yufC7HISIOCrwEAib2kC5EEQn5+wKVE/bnZryVX2leT
YXdfItDCBU6zCYUA+wTU5hGGn9lcDUcZx72l/KZPDyPw7HdzNJ+6iR1zQqoM
=f9kv
-----END PGP SIGNATURE-----
Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Daniel Borkmann:
- Fix BPF verifier to not affect subreg_def marks in its range
propagation (Eduard Zingerman)
- Fix a truncation bug in the BPF verifier's handling of
coerce_reg_to_size_sx (Dimitar Kanaliev)
- Fix the BPF verifier's delta propagation between linked registers
under 32-bit addition (Daniel Borkmann)
- Fix a NULL pointer dereference in BPF devmap due to missing rxq
information (Florian Kauer)
- Fix a memory leak in bpf_core_apply (Jiri Olsa)
- Fix an UBSAN-reported array-index-out-of-bounds in BTF parsing for
arrays of nested structs (Hou Tao)
- Fix build ID fetching where memory areas backing the file were
created with memfd_secret (Andrii Nakryiko)
- Fix BPF task iterator tid filtering which was incorrectly using pid
instead of tid (Jordan Rome)
- Several fixes for BPF sockmap and BPF sockhash redirection in
combination with vsocks (Michal Luczaj)
- Fix riscv BPF JIT and make BPF_CMPXCHG fully ordered (Andrea Parri)
- Fix riscv BPF JIT under CONFIG_CFI_CLANG to prevent the possibility
of an infinite BPF tailcall (Pu Lehui)
- Fix a build warning from resolve_btfids that bpf_lsm_key_free cannot
be resolved (Thomas Weißschuh)
- Fix a bug in kfunc BTF caching for modules where the wrong BTF object
was returned (Toke Høiland-Jørgensen)
- Fix a BPF selftest compilation error in cgroup-related tests with
musl libc (Tony Ambardar)
- Several fixes to BPF link info dumps to fill missing fields (Tyrone
Wu)
- Add BPF selftests for kfuncs from multiple modules, checking that the
correct kfuncs are called (Simon Sundberg)
- Ensure that internal and user-facing bpf_redirect flags don't overlap
(Toke Høiland-Jørgensen)
- Switch to use kvzmalloc to allocate BPF verifier environment (Rik van
Riel)
- Use raw_spinlock_t in BPF ringbuf to fix a sleep in atomic splat
under RT (Wander Lairson Costa)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (38 commits)
lib/buildid: Handle memfd_secret() files in build_id_parse()
selftests/bpf: Add test case for delta propagation
bpf: Fix print_reg_state's constant scalar dump
bpf: Fix incorrect delta propagation between linked registers
bpf: Properly test iter/task tid filtering
bpf: Fix iter/task tid filtering
riscv, bpf: Make BPF_CMPXCHG fully ordered
bpf, vsock: Drop static vsock_bpf_prot initialization
vsock: Update msg_count on read_skb()
vsock: Update rx_bytes on read_skb()
bpf, sockmap: SK_DROP on attempted redirects of unsupported af_vsock
selftests/bpf: Add asserts for netfilter link info
bpf: Fix link info netfilter flags to populate defrag flag
selftests/bpf: Add test for sign extension in coerce_subreg_to_size_sx()
selftests/bpf: Add test for truncation after sign extension in coerce_reg_to_size_sx()
bpf: Fix truncation bug in coerce_reg_to_size_sx()
selftests/bpf: Assert link info uprobe_multi count & path_size if unset
bpf: Fix unpopulated path_size when uprobe_multi fields unset
selftests/bpf: Fix cross-compiling urandom_read
selftests/bpf: Add test for kfunc module order
...
Conflicts:
kernel/sched/ext.c
There's a context conflict between this upstream commit:
3fdb9ebcec sched_ext: Start schedulers with consistent p->scx.slice values
... and this fix in sched/urgent:
98442f0ccd sched: Fix delayed_dequeue vs switched_from_fair()
Resolve it.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A ring buffer which has its buffered mapped at boot up to fixed memory
should not be freed. Other buffers can be. The ref counting setup was
wrong for both. It made the not mapped buffers ref count have zero, and the
boot mapped buffer a ref count of 1. But an normally allocated buffer
should be 1, where it can be removed.
Keep the ref count of a normal boot buffer with its setup ref count (do
not decrement it), and increment the fixed memory boot mapped buffer's ref
count.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241011165224.33dd2624@gandalf.local.home
Fixes: e645535a95 ("tracing: Add option to use memmapped memory for trace boot instance")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Sean noted that ever since commit 152e11f6df ("sched/fair: Implement
delayed dequeue") KVM's preemption notifiers have started
mis-classifying preemption vs blocking.
Notably p->on_rq is no longer sufficient to determine if a task is
runnable or blocked -- the aforementioned commit introduces tasks that
remain on the runqueue even through they will not run again, and
should be considered blocked for many cases.
Add the task_is_runnable() helper to classify things and audit all
external users of the p->on_rq state. Also add a few comments.
Fixes: 152e11f6df ("sched/fair: Implement delayed dequeue")
Reported-by: Sean Christopherson <seanjc@google.com>
Tested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20241010091843.GK33184@noisy.programming.kicks-ass.net
Previously when retrieving `bpf_link_info.uprobe_multi` with `path` and
`path_size` fields unset, the `path_size` field is not populated
(remains 0). This behavior was inconsistent with how other input/output
string buffer fields work, as the field should be populated in cases
when:
- both buffer and length are set (currently works as expected)
- both buffer and length are unset (not working as expected)
This patch now fills the `path_size` field when `path` and `path_size`
are unset.
Fixes: e56fdbfb06 ("bpf: Add link_info support for uprobe multi link")
Signed-off-by: Tyrone Wu <wudevelops@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241011000803.681190-1-wudevelops@gmail.com
ftrace_regs was created to hold registers that store information to save
function parameters, return value and stack. Since it is a subset of
pt_regs, it should only be used by its accessor functions. But because
pt_regs can easily be taken from ftrace_regs (on most archs), it is
tempting to use it directly. But when running on other architectures, it
may fail to build or worse, build but crash the kernel!
Instead, make struct ftrace_regs an empty structure and have the
architectures define __arch_ftrace_regs and all the accessor functions
will typecast to it to get to the actual fields. This will help avoid
usage of ftrace_regs directly.
Link: https://lore.kernel.org/all/20241007171027.629bdafd@gandalf.local.home/
Cc: "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>
Cc: "x86@kernel.org" <x86@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/20241008230628.958778821@goodmis.org
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function call_filter_check_discard() has been removed in the
commit 49e4154f4b ("tracing: Remove TRACE_EVENT_FL_FILTERED logic"),
from another topic branch. But when merged together with commit
21e92806d3 ("function_graph: Support recording and printing the
function return address") which added another call to
call_filter_check_discard(), it caused the build to fail. Since the
function call_filter_check_discard() is useless, it can simply be removed
regardless of being merged with commit 49e4154f4b or not.
Link: https://lore.kernel.org/all/20241010134649.43ed357c@canb.auug.org.au/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Donglin Peng <dolinux.peng@gmail.com>
Link: https://lore.kernel.org/20241010194020.46192b21@gandalf.local.home
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 21e92806d3 ("function_graph: Support recording and printing the function return address")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Simplify return address printing in the function graph tracer by removing
fgraph_extras. Since this feature is only used by the function graph
tracer and the feature flags can directly accessible from the function
graph tracer, fgraph_extras can be removed from the fgraph callback.
Cc: Donglin Peng <dolinux.peng@gmail.com>
Link: https://lore.kernel.org/172857234900.270774.15378354017601069781.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Use atomic64_inc_return(&ref) instead of atomic64_add_return(1, &ref)
to use optimized implementation and ease register pressure around
the primitive for targets that implement optimized variant.
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241007085651.48544-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When a tracepoint event is created with attr.freq = 1,
'hwc->period_left' is not initialized correctly. As a result,
in the perf_swevent_overflow() function, when the first time the event occurs,
it calculates the event overflow and the perf_swevent_set_period() returns 3,
this leads to the event are recorded for three duplicate times.
Step to reproduce:
1. Enable the tracepoint event & starting tracing
$ echo 1 > /sys/kernel/tracing/events/module/module_free
$ echo 1 > /sys/kernel/tracing/tracing_on
2. Record with perf
$ perf record -a --strict-freq -F 1 -e "module:module_free"
3. Trigger module_free event.
$ modprobe -i sunrpc
$ modprobe -r sunrpc
Result:
- Trace pipe result:
$ cat trace_pipe
modprobe-174509 [003] ..... 6504.868896: module_free: sunrpc
- perf sample:
modprobe 174509 [003] 6504.868980: module:module_free: sunrpc
modprobe 174509 [003] 6504.868980: module:module_free: sunrpc
modprobe 174509 [003] 6504.868980: module:module_free: sunrpc
By setting period_left via perf_swevent_set_period() as other sw_event did,
This problem could be solved.
After patch:
- Trace pipe result:
$ cat trace_pipe
modprobe 1153096 [068] 613468.867774: module:module_free: xfs
- perf sample
modprobe 1153096 [068] 613468.867794: module:module_free: xfs
Link: https://lore.kernel.org/20240913021347.595330-1-yeoreum.yun@arm.com
Fixes: bd2b5b1284 ("perf_counter: More aggressive frequency adjustment")
Signed-off-by: Levi Yun <yeoreum.yun@arm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a might_fault() check to validate that the perf sys_enter/sys_exit
probe callbacks are indeed called from a context where page faults can
be handled.
Cc: Michael Jeanson <mjeanson@efficios.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes <joel@joelfernandes.org>
Link: https://lore.kernel.org/20241009010718.2050182-8-mathieu.desnoyers@efficios.com
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a might_fault() check to validate that the ftrace sys_enter/sys_exit
probe callbacks are indeed called from a context where page faults can
be handled.
Cc: Michael Jeanson <mjeanson@efficios.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes <joel@joelfernandes.org>
Link: https://lore.kernel.org/20241009010718.2050182-7-mathieu.desnoyers@efficios.com
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In preparation for allowing system call enter/exit instrumentation to
handle page faults, make sure that perf can handle this change by
explicitly disabling preemption within the perf system call tracepoint
probes to respect the current expectations within perf ring buffer code.
This change does not yet allow perf to take page faults per se within
its probe, but allows its existing probes to adapt to the upcoming
change.
Cc: Michael Jeanson <mjeanson@efficios.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes <joel@joelfernandes.org>
Link: https://lore.kernel.org/20241009010718.2050182-4-mathieu.desnoyers@efficios.com
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In preparation for allowing system call enter/exit instrumentation to
handle page faults, make sure that ftrace can handle this change by
explicitly disabling preemption within the ftrace system call tracepoint
probes to respect the current expectations within ftrace ring buffer
code.
This change does not yet allow ftrace to take page faults per se within
its probe, but allows its existing probes to adapt to the upcoming
change.
Cc: Michael Jeanson <mjeanson@efficios.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes <joel@joelfernandes.org>
Link: https://lore.kernel.org/20241009010718.2050182-3-mathieu.desnoyers@efficios.com
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The boot mapped ring buffer has its buffer mapped at a fixed location
found at boot up. It is not dynamic. It cannot grow or be expanded when
new CPUs come online.
Do not hook fixed memory mapped ring buffers to the CPU hotplug callback,
otherwise it can cause a crash when it tries to add the buffer to the
memory that is already fully occupied.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241008143242.25e20801@gandalf.local.home
Fixes: be68d63a13 ("ring-buffer: Add ring_buffer_alloc_range()")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The trace_*_rcuidle() variant of a tracepoint was to handle places where a
tracepoint was located but RCU was not "watching". All those locations
have been removed, and RCU should be watching where all tracepoints are
located. We can now remove the trace_*_rcuidle() variant.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Link: https://lore.kernel.org/20241003181629.36209057@gandalf.local.home
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The old static key API is deprecated. Switch to the new one.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/7a08dae3c5eddb14b13864923c1b58ac1f4af83c.1728414936.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
After commit dcb0b5575d ("tracing: Remove TRACE_EVENT_FL_USE_CALL_FILTER
logic"), no one's going to set the TRACE_EVENT_FL_FILTERED or change the
call->filter, so remove related logic.
Link: https://lore.kernel.org/20240911010026.2302849-1-zhengyejian@huaweicloud.com
Signed-off-by: Zheng Yejian <zhengyejian@huaweicloud.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Use this_cpu_ptr() instead of open coding the equivalent in various
ftrace functions.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/87y14t6ofi.wl-me@linux.beauty
Signed-off-by: Li Chen <chenl311@chinatelecom.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
After the commit 29c1c24a27 ("function_graph: Fix up ftrace_graph_ret_addr()")
ftrace_graph_ret_addr() doesn't need to initialize "int i" at the start.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Puranjay Mohan <puranjay@kernel.org>
Link: https://lore.kernel.org/20240916175818.GA28944@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When using function_graph tracer to analyze the flow of kernel function
execution, it is often necessary to quickly locate the exact line of code
where the call occurs. While this may be easy at times, it can be more
time-consuming when some functions are inlined or the flow is too long.
This feature aims to simplify the process by recording the return address
of traced funcions and printing it when outputing trace logs.
To enhance human readability, the prefix 'ret=' is used for the kernel return
value, while '<-' serves as the prefix for the return address in trace logs to
make it look more like the function tracer.
A new trace option named 'funcgraph-retaddr' has been introduced, and the
existing option 'sym-addr' can be used to control the format of the return
address.
See below logs with both funcgraph-retval and funcgraph-retaddr enabled.
0) | load_elf_binary() { /* <-bprm_execve+0x249/0x600 */
0) | load_elf_phdrs() { /* <-load_elf_binary+0x84/0x1730 */
0) | __kmalloc_noprof() { /* <-load_elf_phdrs+0x4a/0xb0 */
0) 3.657 us | __cond_resched(); /* <-__kmalloc_noprof+0x28c/0x390 ret=0x0 */
0) + 24.335 us | } /* __kmalloc_noprof ret=0xffff8882007f3000 */
0) | kernel_read() { /* <-load_elf_phdrs+0x6c/0xb0 */
0) | rw_verify_area() { /* <-kernel_read+0x2b/0x50 */
0) | security_file_permission() { /* <-kernel_read+0x2b/0x50 */
0) | selinux_file_permission() { /* <-security_file_permission+0x26/0x40 */
0) | __inode_security_revalidate() { /* <-selinux_file_permission+0x6d/0x140 */
0) 2.034 us | __cond_resched(); /* <-__inode_security_revalidate+0x5f/0x80 ret=0x0 */
0) 6.602 us | } /* __inode_security_revalidate ret=0x0 */
0) 2.214 us | avc_policy_seqno(); /* <-selinux_file_permission+0x107/0x140 ret=0x0 */
0) + 16.670 us | } /* selinux_file_permission ret=0x0 */
0) + 20.809 us | } /* security_file_permission ret=0x0 */
0) + 25.217 us | } /* rw_verify_area ret=0x0 */
0) | __kernel_read() { /* <-load_elf_phdrs+0x6c/0xb0 */
0) | ext4_file_read_iter() { /* <-__kernel_read+0x160/0x2e0 */
Then, we can use the faddr2line to locate the source code, for example:
$ ./scripts/faddr2line ./vmlinux load_elf_phdrs+0x6c/0xb0
load_elf_phdrs+0x6c/0xb0:
elf_read at fs/binfmt_elf.c:471
(inlined by) load_elf_phdrs at fs/binfmt_elf.c:531
Link: https://lore.kernel.org/20240915032912.1118397-1-dolinux.peng@gmail.com
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202409150605.HgUmU8ea-lkp@intel.com/
Signed-off-by: Donglin Peng <dolinux.peng@gmail.com>
[ Rebased to handle text_delta offsets ]
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There is another found exception that the "timerlat/1" thread was
scheduled on CPU0, and lead to timer corruption finally:
```
ODEBUG: init active (active state 0) object: ffff888237c2e108 object type: hrtimer hint: timerlat_irq+0x0/0x220
WARNING: CPU: 0 PID: 426 at lib/debugobjects.c:518 debug_print_object+0x7d/0xb0
Modules linked in:
CPU: 0 UID: 0 PID: 426 Comm: timerlat/1 Not tainted 6.11.0-rc7+ #45
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:debug_print_object+0x7d/0xb0
...
Call Trace:
<TASK>
? __warn+0x7c/0x110
? debug_print_object+0x7d/0xb0
? report_bug+0xf1/0x1d0
? prb_read_valid+0x17/0x20
? handle_bug+0x3f/0x70
? exc_invalid_op+0x13/0x60
? asm_exc_invalid_op+0x16/0x20
? debug_print_object+0x7d/0xb0
? debug_print_object+0x7d/0xb0
? __pfx_timerlat_irq+0x10/0x10
__debug_object_init+0x110/0x150
hrtimer_init+0x1d/0x60
timerlat_main+0xab/0x2d0
? __pfx_timerlat_main+0x10/0x10
kthread+0xb7/0xe0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2d/0x40
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
```
After tracing the scheduling event, it was discovered that the migration
of the "timerlat/1" thread was performed during thread creation. Further
analysis confirmed that it is because the CPU online processing for
osnoise is implemented through workers, which is asynchronous with the
offline processing. When the worker was scheduled to create a thread, the
CPU may has already been removed from the cpu_online_mask during the offline
process, resulting in the inability to select the right CPU:
T1 | T2
[CPUHP_ONLINE] | cpu_device_down()
osnoise_hotplug_workfn() |
| cpus_write_lock()
| takedown_cpu(1)
| cpus_write_unlock()
[CPUHP_OFFLINE] |
cpus_read_lock() |
start_kthread(1) |
cpus_read_unlock() |
To fix this, skip online processing if the CPU is already offline.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20240924094515.3561410-4-liwei391@huawei.com
Fixes: c8895e271f ("trace/osnoise: Support hotplug operations")
Signed-off-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
stop_kthread() is the offline callback for "trace/osnoise:online", since
commit 5bfbcd1ee5 ("tracing/timerlat: Add interface_lock around clearing
of kthread in stop_kthread()"), the following ABBA deadlock scenario is
introduced:
T1 | T2 [BP] | T3 [AP]
osnoise_hotplug_workfn() | work_for_cpu_fn() | cpuhp_thread_fun()
| _cpu_down() | osnoise_cpu_die()
mutex_lock(&interface_lock) | | stop_kthread()
| cpus_write_lock() | mutex_lock(&interface_lock)
cpus_read_lock() | cpuhp_kick_ap() |
As the interface_lock here in just for protecting the "kthread" field of
the osn_var, use xchg() instead to fix this issue. Also use
for_each_online_cpu() back in stop_per_cpu_kthreads() as it can take
cpu_read_lock() again.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20240924094515.3561410-3-liwei391@huawei.com
Fixes: 5bfbcd1ee5 ("tracing/timerlat: Add interface_lock around clearing of kthread in stop_kthread()")
Signed-off-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
osnoise_hotplug_workfn() is the asynchronous online callback for
"trace/osnoise:online". It may be congested when a CPU goes online and
offline repeatedly and is invoked for multiple times after a certain
online.
This will lead to kthread leak and timer corruption. Add a check
in start_kthread() to prevent this situation.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20240924094515.3561410-2-liwei391@huawei.com
Fixes: c8895e271f ("trace/osnoise: Support hotplug operations")
Signed-off-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the tp_printk kernel command line is used, the trace events go
directly to printk(). It is still checked via the trace_check_vprintf()
function to make sure the pointers of the trace event are legit.
The addition of reading buffers from previous boots required adding a
delta between the addresses of the previous boot and the current boot so
that the pointers in the old buffer can still be used. But this required
adding a trace_array pointer to acquire the delta offsets.
The tp_printk code does not provide a trace_array (tr) pointer, so when
the offsets were examined, a NULL pointer dereference happened and the
kernel crashed.
If the trace_array does not exist, just default the delta offsets to zero,
as that also means the trace event is not being read from a previous boot.
Link: https://lore.kernel.org/all/Zv3z5UsG_jsO9_Tb@aschofie-mobl2.lan/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241003104925.4e1b1fd9@gandalf.local.home
Fixes: 07714b4bb3 ("tracing: Handle old buffer mappings for event strings and functions")
Reported-by: Alison Schofield <alison.schofield@intel.com>
Tested-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The calltime field in the shadow stack frame is only used by the function
graph tracer and profiler. But now that there's other users of the function
graph infrastructure, this adds overhead and wastes space on the shadow
stack. Move the calltime to the fgraph data storage, where the function
graph and profiler entry functions will save it in its own graph storage and
retrieve it in its exit functions.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Link: https://lore.kernel.org/20240914214827.096968730@goodmis.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The fgraph "sleep-time" option tells the function graph tracer and the
profiler whether to include the time a function "sleeps" (is scheduled off
the CPU) in its duration for the function. By default it is true, which
means the duration of a function is calculated by the timestamp of when the
function was entered to the timestamp of when it exits.
If the "sleep-time" option is disabled, it needs to remove the time that the
task was not running on the CPU during the function. Currently it is done in
a sched_switch tracepoint probe where it moves the "calltime" (time of entry
of the function) forward by the sleep time calculated. It updates all the
calltime in the shadow stack.
This is time consuming for those users of the function graph tracer that
does not care about the sleep time. Instead, add a "ftrace_sleeptime" to the
task_struct that gets the sleep time added each time the task wakes up. Then
have the function entry save the current "ftrace_sleeptime" and on function
exit, move the calltime forward by the difference of the current
"ftrace_sleeptime" from the saved sleeptime.
This removes one dependency of "calltime" needed to be on the shadow stack.
It also simplifies the code that removes the sleep time of functions.
TODO: Only enable the sched_switch tracepoint when this is needed.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Link: https://lore.kernel.org/20240914214826.938908568@goodmis.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Instead of having the "subtime" for the function profiler in the
infrastructure ftrace_ret_stack structure, have it use the fgraph data
reserve and retrieve functions.
This will keep the limited shadow stack from wasting 8 bytes for something
that is seldom used.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Link: https://lore.kernel.org/20240914214826.780323141@goodmis.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Since the new fgraph requires to initialize fgraph_ops.ops.func_hash before
calling register_ftrace_graph(), initialize it with default (tracing all
functions) parameter.
Cc: stable@vger.kernel.org
Fixes: 5fccc7552c ("ftrace: Add subops logic to allow one ops to manage many")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
no_llseek had been defined to NULL two years ago, in commit 868941b144
("fs: remove no_llseek")
To quote that commit,
At -rc1 we'll need do a mechanical removal of no_llseek -
git grep -l -w no_llseek | grep -v porting.rst | while read i; do
sed -i '/\<no_llseek\>/d' $i
done
would do it.
Unfortunately, that hadn't been done. Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
.llseek = no_llseek,
so it's obviously safe.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- uprobes: make trace_uprobe->nhit counter a per-CPU one
This makes uprobe event's hit counter per-CPU for improving
scalability on multi-core environment.
- kprobes: Remove obsoleted declaration for init_test_probes
Remove unused init_test_probes() from header.
- Raw tracepoint probe supports raw tracepoint events on modules.
The tracepoint events using fprobe were introduced in v6.5, but
tracepoints can be compiled in modules. This supports such a case.
This includes the following improvements.
. tracepoint: add a function for iterating over all tracepoints in
all modules.
. tracepoint: Add a function for iterating over tracepoints in a
module.
. tracing/fprobe: Support raw tracepoint events on modules.
. tracing/fprobe: Support raw tracepoints on future loaded modules.
This allows user to add tracepoint events on modules which is
not loaded yet.
. selftests/tracing: Add a test for tracepoint events on modules.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCgAdFiEEh7BulGwFlgAOi5DV2/sHvwUrPxsFAmb0HXgACgkQ2/sHvwUr
Pxs7AAf+K89Q7eyqKLP/oG5LGsnmWwhZHP26HTbGKh7mRaxGE+cf3l1O2lCMAgBt
0Y1J0sHkgRSnubmlPrgEMKKLOKVBwnvwBqbqO8Zw8L3GxMegG5YYsl3Y60Q0T6Gq
xiL17sHILbb/yefUqnf6C3QHoSjR4aTMEaQSpux1tsCqG/sLeU7V6DZrWdM5t4Fl
CvQDuy//UdQUKFTUC5XOc6lRbKr94ktp/VTxdHZLXa5u6p/slq8ISf9EA+Rrsjkp
m+FtW8MpfcYt3K+hs0kV58F43XWeRt9F7OlLf+MlyCeRRQor4xvkVlV0iw6VcRG9
sXt6ml6AmyA2JWRzR5qSKYvMAsNVyA==
=GYlS
-----END PGP SIGNATURE-----
Merge tag 'probes-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes updates from Masami Hiramatsu:
- uprobes: make trace_uprobe->nhit counter a per-CPU one
This makes uprobe event's hit counter per-CPU for improving
scalability on multi-core environment
- kprobes: Remove obsoleted declaration for init_test_probes
Remove unused init_test_probes() from header
- Raw tracepoint probe supports raw tracepoint events on modules:
- add a function for iterating over all tracepoints in all modules
- add a function for iterating over tracepoints in a module
- support raw tracepoint events on modules
- support raw tracepoints on future loaded modules
- add a test for tracepoint events on modules"
* tag 'probes-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
sefltests/tracing: Add a test for tracepoint events on modules
tracing/fprobe: Support raw tracepoints on future loaded modules
tracing/fprobe: Support raw tracepoint events on modules
tracepoint: Support iterating tracepoints in a loading module
tracepoint: Support iterating over tracepoints on modules
kprobes: Remove obsoleted declaration for init_test_probes
uprobes: turn trace_uprobe's nhit counter to be per-CPU one
Support raw tracepoint events on future loaded (unloaded) modules.
This allows user to create raw tracepoint events which can be used from
module's __init functions.
Note: since the kernel does not have any information about the tracepoints
in the unloaded modules, fprobe events can not check whether the tracepoint
exists nor extend the BTF based arguments.
Link: https://lore.kernel.org/all/172397780593.286558.18360375226968537828.stgit@devnote2/
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
trace_uprobe->nhit counter is not incremented atomically, so its value
is questionable in when uprobe is hit on multiple CPUs simultaneously.
Also, doing this shared counter increment across many CPUs causes heavy
cache line bouncing, limiting uprobe/uretprobe performance scaling with
number of CPUs.
Solve both problems by making this a per-CPU counter.
Link: https://lore.kernel.org/all/20240813203409.3985398-1-andrii@kernel.org/
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
- Merged v6.11-rc3 into trace/ring-buffer/core
The v6.10 ring buffer pull request was not made due to Mathieu Desnoyers
making a comment to the pull request. Mathieu and I resolved it on IRC,
but we did not let Linus know that it was resolved. Linus did not do the
pull thinking it still had some unresolved issues.
The ring buffer work for 6.12 was dependent on both this pull request as
well as the reserve_mem kernel command line option that was going upstream
through the memory management tree. The ring buffer repo was being used by
others so it could not be rebased. In order to continue the work, the
v6.11-rc3 branch was pulled in to get access to the reserve_mem work.
This has the 6.11 pull request that did not make it into 6.11, which was:
tracing/ring-buffer: Have persistent buffer across reboots
This allows for the tracing instance ring buffer to stay persistent across
reboots. The way this is done is by adding to the kernel command line:
trace_instance=boot_map@0x285400000:12M
This will reserve 12 megabytes at the address 0x285400000, and then map
the tracing instance "boot_map" ring buffer to that memory. This will
appear as a normal instance in the tracefs system:
/sys/kernel/tracing/instances/boot_map
A user could enable tracing in that instance, and on reboot or kernel
crash, if the memory is not wiped by the firmware, it will recreate the
trace in that instance. For example, if one was debugging a shutdown of a
kernel reboot:
# cd /sys/kernel/tracing
# echo function > instances/boot_map/current_tracer
# reboot
[..]
# cd /sys/kernel/tracing
# tail instances/boot_map/trace
swapper/0-1 [000] d..1. 164.549800: restore_boot_irq_mode <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549801: native_restore_boot_irq_mode <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549802: disconnect_bsp_APIC <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549811: hpet_disable <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549812: iommu_shutdown_noop <-native_machine_restart
swapper/0-1 [000] d..1. 164.549813: native_machine_emergency_restart <-__do_sys_reboot
swapper/0-1 [000] d..1. 164.549813: tboot_shutdown <-native_machine_emergency_restart
swapper/0-1 [000] d..1. 164.549820: acpi_reboot <-native_machine_emergency_restart
swapper/0-1 [000] d..1. 164.549821: acpi_reset <-acpi_reboot
swapper/0-1 [000] d..1. 164.549822: acpi_os_write_port <-acpi_reboot
On reboot, the buffer is examined to make sure it is valid. The validation
check even steps through every event to make sure the meta data of the
event is correct. If any test fails, it will simply reset the buffer, and
the buffer will be empty on boot.
The new changes for 6.12 are:
- Allow the tracing persistent boot buffer to use the "reserve_mem" option
Instead of having the admin find a physical address to store the persistent
buffer, which can be very tedious if they have to administrate several
different machines, allow them to use the "reserve_mem" option that will
find a location for them. It is not as reliable because of KASLR, as the
loading of the kernel in different locations can cause the memory
allocated to be inconsistent. Booting with "nokaslr" can make reserve_mem
more reliable.
- Have function graph tracer handle offsets from a previous boot.
The ring buffer output from a previous boot may have different addresses
due to kaslr. Have the function graph tracer handle these by using the
delta from the previous boot to the new boot address space.
- Only reset the saved meta offset when the buffer is started or reset
In the persistent memory meta data, it holds the previous address space
information, so that it can calculate the delta to have function tracing
work. But this gets updated after being read to hold the new address
space. But if the buffer isn't used for that boot, on reboot, the delta is
now calculated from the previous boot and not the boot that holds the data
in the ring buffer. This causes the functions not to be shown. Do not save
the address space information of the current kernel until it is being
recorded.
- Add a magic variable to test the valid meta data
Add a magic variable in the meta data that can also be used for
validation. The validator of the previous buffer doesn't need this magic
data, but it can be used if the meta data is changed by a new kernel, which
may have the same format that passes the validator but is used
differently. This magic number can also be used as a "versioning" of the
meta data.
- Align user space mapped ring buffer sub buffers to improve TLB entries
Linus mentioned that the mapped ring buffer sub buffers were misaligned
between the meta page and the sub-buffers, so that if the sub-buffers were
bigger than PAGE_SIZE, it wouldn't allow the TLB to use bigger entries.
- Add new kernel command line "traceoff" to disable tracing on boot for instances
If tracing is enabled for a boot instance, there needs a way to be able to
disable it on boot so that new events do not get entered into the ring
buffer and be mixed with events from a previous boot, as that can be
confusing.
- Allow trace_printk() to go to other instances
Currently, trace_printk() can only go to the top level instance. When
debugging with a persistent buffer, it is really useful to be able to add
trace_printk() to go to that buffer, so that you have access to them after
a crash.
- Do not use "bin_printk()" for traces to a boot instance
The bin_printk() saves only a pointer to the printk format in the ring
buffer, as the reader of the buffer can still have access to it. But this
is not the case if the buffer is from a previous boot. If the
trace_printk() is going to a "persistent" buffer, it will use the slower
version that writes the printk format into the buffer.
- Add command line option to allow trace_printk() to go to an instance
Allow the kernel command line to define which instance the trace_printk()
goes to, instead of forcing the admin to set it for every boot via the
tracefs options.
- Start a document that explains how to use tracefs to debug the kernel
- Add some more kernel selftests to test user mapped ring buffer
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZu/PxxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qowiAQCx86Nm48aCACjrvGWCFb+jgQZn8QdO
MeK15Fcc5C3b5gEAkJkDKqtul7ybI9+vq+3yNzdl7pO7Y7+pCNzz3PfVaQA=
=Ce81
-----END PGP SIGNATURE-----
Merge tag 'trace-ring-buffer-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ring-buffer updates from Steven Rostedt:
- tracing/ring-buffer: persistent buffer across reboots
This allows for the tracing instance ring buffer to stay persistent
across reboots. The way this is done is by adding to the kernel
command line:
trace_instance=boot_map@0x285400000:12M
This will reserve 12 megabytes at the address 0x285400000, and then
map the tracing instance "boot_map" ring buffer to that memory. This
will appear as a normal instance in the tracefs system:
/sys/kernel/tracing/instances/boot_map
A user could enable tracing in that instance, and on reboot or kernel
crash, if the memory is not wiped by the firmware, it will recreate
the trace in that instance. For example, if one was debugging a
shutdown of a kernel reboot:
# cd /sys/kernel/tracing
# echo function > instances/boot_map/current_tracer
# reboot
[..]
# cd /sys/kernel/tracing
# tail instances/boot_map/trace
swapper/0-1 [000] d..1. 164.549800: restore_boot_irq_mode <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549801: native_restore_boot_irq_mode <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549802: disconnect_bsp_APIC <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549811: hpet_disable <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549812: iommu_shutdown_noop <-native_machine_restart
swapper/0-1 [000] d..1. 164.549813: native_machine_emergency_restart <-__do_sys_reboot
swapper/0-1 [000] d..1. 164.549813: tboot_shutdown <-native_machine_emergency_restart
swapper/0-1 [000] d..1. 164.549820: acpi_reboot <-native_machine_emergency_restart
swapper/0-1 [000] d..1. 164.549821: acpi_reset <-acpi_reboot
swapper/0-1 [000] d..1. 164.549822: acpi_os_write_port <-acpi_reboot
On reboot, the buffer is examined to make sure it is valid. The
validation check even steps through every event to make sure the meta
data of the event is correct. If any test fails, it will simply reset
the buffer, and the buffer will be empty on boot.
- Allow the tracing persistent boot buffer to use the "reserve_mem"
option
Instead of having the admin find a physical address to store the
persistent buffer, which can be very tedious if they have to
administrate several different machines, allow them to use the
"reserve_mem" option that will find a location for them. It is not as
reliable because of KASLR, as the loading of the kernel in different
locations can cause the memory allocated to be inconsistent. Booting
with "nokaslr" can make reserve_mem more reliable.
- Have function graph tracer handle offsets from a previous boot.
The ring buffer output from a previous boot may have different
addresses due to kaslr. Have the function graph tracer handle these
by using the delta from the previous boot to the new boot address
space.
- Only reset the saved meta offset when the buffer is started or reset
In the persistent memory meta data, it holds the previous address
space information, so that it can calculate the delta to have
function tracing work. But this gets updated after being read to hold
the new address space. But if the buffer isn't used for that boot, on
reboot, the delta is now calculated from the previous boot and not
the boot that holds the data in the ring buffer. This causes the
functions not to be shown. Do not save the address space information
of the current kernel until it is being recorded.
- Add a magic variable to test the valid meta data
Add a magic variable in the meta data that can also be used for
validation. The validator of the previous buffer doesn't need this
magic data, but it can be used if the meta data is changed by a new
kernel, which may have the same format that passes the validator but
is used differently. This magic number can also be used as a
"versioning" of the meta data.
- Align user space mapped ring buffer sub buffers to improve TLB
entries
Linus mentioned that the mapped ring buffer sub buffers were
misaligned between the meta page and the sub-buffers, so that if the
sub-buffers were bigger than PAGE_SIZE, it wouldn't allow the TLB to
use bigger entries.
- Add new kernel command line "traceoff" to disable tracing on boot for
instances
If tracing is enabled for a boot instance, there needs a way to be
able to disable it on boot so that new events do not get entered into
the ring buffer and be mixed with events from a previous boot, as
that can be confusing.
- Allow trace_printk() to go to other instances
Currently, trace_printk() can only go to the top level instance. When
debugging with a persistent buffer, it is really useful to be able to
add trace_printk() to go to that buffer, so that you have access to
them after a crash.
- Do not use "bin_printk()" for traces to a boot instance
The bin_printk() saves only a pointer to the printk format in the
ring buffer, as the reader of the buffer can still have access to it.
But this is not the case if the buffer is from a previous boot. If
the trace_printk() is going to a "persistent" buffer, it will use the
slower version that writes the printk format into the buffer.
- Add command line option to allow trace_printk() to go to an instance
Allow the kernel command line to define which instance the
trace_printk() goes to, instead of forcing the admin to set it for
every boot via the tracefs options.
- Start a document that explains how to use tracefs to debug the kernel
- Add some more kernel selftests to test user mapped ring buffer
* tag 'trace-ring-buffer-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (28 commits)
selftests/ring-buffer: Handle meta-page bigger than the system
selftests/ring-buffer: Verify the entire meta-page padding
tracing/Documentation: Start a document on how to debug with tracing
tracing: Add option to set an instance to be the trace_printk destination
tracing: Have trace_printk not use binary prints if boot buffer
tracing: Allow trace_printk() to go to other instance buffers
tracing: Add "traceoff" flag to boot time tracing instances
ring-buffer: Align meta-page to sub-buffers for improved TLB usage
ring-buffer: Add magic and struct size to boot up meta data
ring-buffer: Don't reset persistent ring-buffer meta saved addresses
tracing/fgraph: Have fgraph handle previous boot function addresses
tracing: Allow boot instances to use reserve_mem boot memory
tracing: Fix ifdef of snapshots to not prevent last_boot_info file
ring-buffer: Use vma_pages() helper function
tracing: Fix NULL vs IS_ERR() check in enable_instances()
tracing: Add last boot delta offset for stack traces
tracing: Update function tracing output for previous boot buffer
tracing: Handle old buffer mappings for event strings and functions
tracing/ring-buffer: Add last_boot_info file to boot instance
ring-buffer: Save text and data locations in mapped meta data
...
-----BEGIN PGP SIGNATURE-----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=MDwh
-----END PGP SIGNATURE-----
Merge tag 'bpf-next-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Introduce '__attribute__((bpf_fastcall))' for helpers and kfuncs with
corresponding support in LLVM.
It is similar to existing 'no_caller_saved_registers' attribute in
GCC/LLVM with a provision for backward compatibility. It allows
compilers generate more efficient BPF code assuming the verifier or
JITs will inline or partially inline a helper/kfunc with such
attribute. bpf_cast_to_kern_ctx, bpf_rdonly_cast,
bpf_get_smp_processor_id are the first set of such helpers.
- Harden and extend ELF build ID parsing logic.
When called from sleepable context the relevants parts of ELF file
will be read to find and fetch .note.gnu.build-id information. Also
harden the logic to avoid TOCTOU, overflow, out-of-bounds problems.
- Improvements and fixes for sched-ext:
- Allow passing BPF iterators as kfunc arguments
- Make the pointer returned from iter_next method trusted
- Fix x86 JIT convergence issue due to growing/shrinking conditional
jumps in variable length encoding
- BPF_LSM related:
- Introduce few VFS kfuncs and consolidate them in
fs/bpf_fs_kfuncs.c
- Enforce correct range of return values from certain LSM hooks
- Disallow attaching to other LSM hooks
- Prerequisite work for upcoming Qdisc in BPF:
- Allow kptrs in program provided structs
- Support for gen_epilogue in verifier_ops
- Important fixes:
- Fix uprobe multi pid filter check
- Fix bpf_strtol and bpf_strtoul helpers
- Track equal scalars history on per-instruction level
- Fix tailcall hierarchy on x86 and arm64
- Fix signed division overflow to prevent INT_MIN/-1 trap on x86
- Fix get kernel stack in BPF progs attached to tracepoint:syscall
- Selftests:
- Add uprobe bench/stress tool
- Generate file dependencies to drastically improve re-build time
- Match JIT-ed and BPF asm with __xlated/__jited keywords
- Convert older tests to test_progs framework
- Add support for RISC-V
- Few fixes when BPF programs are compiled with GCC-BPF backend
(support for GCC-BPF in BPF CI is ongoing in parallel)
- Add traffic monitor
- Enable cross compile and musl libc
* tag 'bpf-next-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (260 commits)
btf: require pahole 1.21+ for DEBUG_INFO_BTF with default DWARF version
btf: move pahole check in scripts/link-vmlinux.sh to lib/Kconfig.debug
btf: remove redundant CONFIG_BPF test in scripts/link-vmlinux.sh
bpf: Call the missed kfree() when there is no special field in btf
bpf: Call the missed btf_record_free() when map creation fails
selftests/bpf: Add a test case to write mtu result into .rodata
selftests/bpf: Add a test case to write strtol result into .rodata
selftests/bpf: Rename ARG_PTR_TO_LONG test description
selftests/bpf: Fix ARG_PTR_TO_LONG {half-,}uninitialized test
bpf: Zero former ARG_PTR_TO_{LONG,INT} args in case of error
bpf: Improve check_raw_mode_ok test for MEM_UNINIT-tagged types
bpf: Fix helper writes to read-only maps
bpf: Remove truncation test in bpf_strtol and bpf_strtoul helpers
bpf: Fix bpf_strtol and bpf_strtoul helpers for 32bit
selftests/bpf: Add tests for sdiv/smod overflow cases
bpf: Fix a sdiv overflow issue
libbpf: Add bpf_object__token_fd accessor
docs/bpf: Add missing BPF program types to docs
docs/bpf: Add constant values for linkages
bpf: Use fake pt_regs when doing bpf syscall tracepoint tracing
...
- Implement the SCHED_DEADLINE server infrastructure - Daniel Bristot de Oliveira's
last major contribution to the kernel:
"SCHED_DEADLINE servers can help fixing starvation issues of low priority
tasks (e.g., SCHED_OTHER) when higher priority tasks monopolize CPU
cycles. Today we have RT Throttling; DEADLINE servers should be able to
replace and improve that."
(Daniel Bristot de Oliveira, Peter Zijlstra, Joel Fernandes,
Youssef Esmat, Huang Shijie)
- Preparatory changes for sched_ext integration:
- Use set_next_task(.first) where required
- Fix up set_next_task() implementations
- Clean up DL server vs. core sched
- Split up put_prev_task_balance()
- Rework pick_next_task()
- Combine the last put_prev_task() and the first set_next_task()
- Rework dl_server
- Add put_prev_task(.next)
(Peter Zijlstra, with a fix by Tejun Heo)
- Complete the EEVDF transition and refine EEVDF scheduling:
- Implement delayed dequeue
- Allow shorter slices to wakeup-preempt
- Use sched_attr::sched_runtime to set request/slice suggestion
- Document the new feature flags
- Remove unused and duplicate-functionality fields
- Simplify & unify pick_next_task_fair()
- Misc debuggability enhancements
(Peter Zijlstra, with fixes/cleanups by Dietmar Eggemann,
Valentin Schneider and Chuyi Zhou)
- Initialize the vruntime of a new task when it is first enqueued,
resulting in significant decrease in latency of newly woken tasks.
(Zhang Qiao)
- Introduce SM_IDLE and an idle re-entry fast-path in __schedule()
(K Prateek Nayak, Peter Zijlstra)
- Clean up and clarify the usage of Clean up usage of rt_task()
(Qais Yousef)
- Preempt SCHED_IDLE entities in strict cgroup hierarchies
(Tianchen Ding)
- Clarify the documentation of time units for deadline scheduler
parameters. (Christian Loehle)
- Remove the HZ_BW chicken-bit feature flag introduced a year ago,
the original change seems to be working fine.
(Phil Auld)
- Misc fixes and cleanups (Chen Yu, Dan Carpenter, Huang Shijie,
Peilin He, Qais Yousefm and Vincent Guittot)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=TEC6
-----END PGP SIGNATURE-----
Merge tag 'sched-core-2024-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
- Implement the SCHED_DEADLINE server infrastructure - Daniel Bristot
de Oliveira's last major contribution to the kernel:
"SCHED_DEADLINE servers can help fixing starvation issues of low
priority tasks (e.g., SCHED_OTHER) when higher priority tasks
monopolize CPU cycles. Today we have RT Throttling; DEADLINE
servers should be able to replace and improve that."
(Daniel Bristot de Oliveira, Peter Zijlstra, Joel Fernandes, Youssef
Esmat, Huang Shijie)
- Preparatory changes for sched_ext integration:
- Use set_next_task(.first) where required
- Fix up set_next_task() implementations
- Clean up DL server vs. core sched
- Split up put_prev_task_balance()
- Rework pick_next_task()
- Combine the last put_prev_task() and the first set_next_task()
- Rework dl_server
- Add put_prev_task(.next)
(Peter Zijlstra, with a fix by Tejun Heo)
- Complete the EEVDF transition and refine EEVDF scheduling:
- Implement delayed dequeue
- Allow shorter slices to wakeup-preempt
- Use sched_attr::sched_runtime to set request/slice suggestion
- Document the new feature flags
- Remove unused and duplicate-functionality fields
- Simplify & unify pick_next_task_fair()
- Misc debuggability enhancements
(Peter Zijlstra, with fixes/cleanups by Dietmar Eggemann, Valentin
Schneider and Chuyi Zhou)
- Initialize the vruntime of a new task when it is first enqueued,
resulting in significant decrease in latency of newly woken tasks
(Zhang Qiao)
- Introduce SM_IDLE and an idle re-entry fast-path in __schedule()
(K Prateek Nayak, Peter Zijlstra)
- Clean up and clarify the usage of Clean up usage of rt_task()
(Qais Yousef)
- Preempt SCHED_IDLE entities in strict cgroup hierarchies
(Tianchen Ding)
- Clarify the documentation of time units for deadline scheduler
parameters (Christian Loehle)
- Remove the HZ_BW chicken-bit feature flag introduced a year ago,
the original change seems to be working fine (Phil Auld)
- Misc fixes and cleanups (Chen Yu, Dan Carpenter, Huang Shijie,
Peilin He, Qais Yousefm and Vincent Guittot)
* tag 'sched-core-2024-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
sched/cpufreq: Use NSEC_PER_MSEC for deadline task
cpufreq/cppc: Use NSEC_PER_MSEC for deadline task
sched/deadline: Clarify nanoseconds in uapi
sched/deadline: Convert schedtool example to chrt
sched/debug: Fix the runnable tasks output
sched: Fix sched_delayed vs sched_core
kernel/sched: Fix util_est accounting for DELAY_DEQUEUE
kthread: Fix task state in kthread worker if being frozen
sched/pelt: Use rq_clock_task() for hw_pressure
sched/fair: Move effective_cpu_util() and effective_cpu_util() in fair.c
sched/core: Introduce SM_IDLE and an idle re-entry fast-path in __schedule()
sched: Add put_prev_task(.next)
sched: Rework dl_server
sched: Combine the last put_prev_task() and the first set_next_task()
sched: Rework pick_next_task()
sched: Split up put_prev_task_balance()
sched: Clean up DL server vs core sched
sched: Fixup set_next_task() implementations
sched: Use set_next_task(.first) where required
sched/fair: Properly deactivate sched_delayed task upon class change
...
- Implement per-PMU context rescheduling to significantly improve single-PMU
performance, and related cleanups/fixes. (by Peter Zijlstra and Namhyung Kim)
- Fix ancient bug resulting in a lot of events being dropped erroneously
at higher sampling frequencies. (by Luo Gengkun)
- uprobes enhancements:
- Implement RCU-protected hot path optimizations for better performance:
"For baseline vs SRCU, peak througput increased from 3.7 M/s (million uprobe
triggerings per second) up to about 8 M/s. For uretprobes it's a bit more
modest with bump from 2.4 M/s to 5 M/s.
For SRCU vs RCU Tasks Trace, peak throughput for uprobes increases further from
8 M/s to 10.3 M/s (+28%!), and for uretprobes from 5.3 M/s to 5.8 M/s (+11%),
as we have more work to do on uretprobes side.
Even single-thread (no contention) performance is slightly better: 3.276 M/s to
3.396 M/s (+3.5%) for uprobes, and 2.055 M/s to 2.174 M/s (+5.8%)
for uretprobes."
(by Andrii Nakryiko et al)
- Document mmap_lock, don't abuse get_user_pages_remote(). (by Oleg Nesterov)
- Cleanups & fixes to prepare for future work:
- Remove uprobe_register_refctr()
- Simplify error handling for alloc_uprobe()
- Make uprobe_register() return struct uprobe *
- Fold __uprobe_unregister() into uprobe_unregister()
- Shift put_uprobe() from delete_uprobe() to uprobe_unregister()
- BPF: Fix use-after-free in bpf_uprobe_multi_link_attach()
(by Oleg Nesterov)
- New feature & ABI extension: allow events to use PERF_SAMPLE READ with
inheritance, enabling sample based profiling of a group of counters over
a hierarchy of processes or threads. (by Ben Gainey)
- Intel uncore & power events updates:
- Add Arrow Lake and Lunar Lake support
- Add PERF_EV_CAP_READ_SCOPE
- Clean up and enhance cpumask and hotplug support
(by Kan Liang)
- Add LNL uncore iMC freerunning support
- Use D0:F0 as a default device
(by Zhenyu Wang)
- Intel PT: fix AUX snapshot handling race. (by Adrian Hunter)
- Misc fixes and cleanups. (by James Clark, Jiri Olsa, Oleg Nesterov and Peter Zijlstra)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=E3s3
-----END PGP SIGNATURE-----
Merge tag 'perf-core-2024-09-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf events updates from Ingo Molnar:
- Implement per-PMU context rescheduling to significantly improve
single-PMU performance, and related cleanups/fixes (Peter Zijlstra
and Namhyung Kim)
- Fix ancient bug resulting in a lot of events being dropped
erroneously at higher sampling frequencies (Luo Gengkun)
- uprobes enhancements:
- Implement RCU-protected hot path optimizations for better
performance:
"For baseline vs SRCU, peak througput increased from 3.7 M/s
(million uprobe triggerings per second) up to about 8 M/s. For
uretprobes it's a bit more modest with bump from 2.4 M/s to
5 M/s.
For SRCU vs RCU Tasks Trace, peak throughput for uprobes
increases further from 8 M/s to 10.3 M/s (+28%!), and for
uretprobes from 5.3 M/s to 5.8 M/s (+11%), as we have more
work to do on uretprobes side.
Even single-thread (no contention) performance is slightly
better: 3.276 M/s to 3.396 M/s (+3.5%) for uprobes, and 2.055
M/s to 2.174 M/s (+5.8%) for uretprobes."
(Andrii Nakryiko et al)
- Document mmap_lock, don't abuse get_user_pages_remote() (Oleg
Nesterov)
- Cleanups & fixes to prepare for future work:
- Remove uprobe_register_refctr()
- Simplify error handling for alloc_uprobe()
- Make uprobe_register() return struct uprobe *
- Fold __uprobe_unregister() into uprobe_unregister()
- Shift put_uprobe() from delete_uprobe() to uprobe_unregister()
- BPF: Fix use-after-free in bpf_uprobe_multi_link_attach()
(Oleg Nesterov)
- New feature & ABI extension: allow events to use PERF_SAMPLE READ
with inheritance, enabling sample based profiling of a group of
counters over a hierarchy of processes or threads (Ben Gainey)
- Intel uncore & power events updates:
- Add Arrow Lake and Lunar Lake support
- Add PERF_EV_CAP_READ_SCOPE
- Clean up and enhance cpumask and hotplug support
(Kan Liang)
- Add LNL uncore iMC freerunning support
- Use D0:F0 as a default device
(Zhenyu Wang)
- Intel PT: fix AUX snapshot handling race (Adrian Hunter)
- Misc fixes and cleanups (James Clark, Jiri Olsa, Oleg Nesterov and
Peter Zijlstra)
* tag 'perf-core-2024-09-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
dmaengine: idxd: Clean up cpumask and hotplug for perfmon
iommu/vt-d: Clean up cpumask and hotplug for perfmon
perf/x86/intel/cstate: Clean up cpumask and hotplug
perf: Add PERF_EV_CAP_READ_SCOPE
perf: Generic hotplug support for a PMU with a scope
uprobes: perform lockless SRCU-protected uprobes_tree lookup
rbtree: provide rb_find_rcu() / rb_find_add_rcu()
perf/uprobe: split uprobe_unregister()
uprobes: travers uprobe's consumer list locklessly under SRCU protection
uprobes: get rid of enum uprobe_filter_ctx in uprobe filter callbacks
uprobes: protected uprobe lifetime with SRCU
uprobes: revamp uprobe refcounting and lifetime management
bpf: Fix use-after-free in bpf_uprobe_multi_link_attach()
perf/core: Fix small negative period being ignored
perf: Really fix event_function_call() locking
perf: Optimize __pmu_ctx_sched_out()
perf: Add context time freeze
perf: Fix event_function_call() locking
perf: Extract a few helpers
perf: Optimize context reschedule for single PMU cases
...
This pull request contains the following branches:
context_tracking.15.08.24a: Rename context tracking state related
symbols and remove references to "dynticks" in various context
tracking state variables and related helpers; force
context_tracking_enabled_this_cpu() to be inlined to avoid
leaving a noinstr section.
csd.lock.15.08.24a: Enhance CSD-lock diagnostic reports; add an API
to provide an indication of ongoing CSD-lock stall.
nocb.09.09.24a: Update and simplify RCU nocb code to handle
(de-)offloading of callbacks only for offline CPUs; fix RT
throttling hrtimer being armed from offline CPU.
rcutorture.14.08.24a: Remove redundant rcu_torture_ops get_gp_completed
fields; add SRCU ->same_gp_state and ->get_comp_state
functions; add generic test for NUM_ACTIVE_*RCU_POLL* for
testing RCU and SRCU polled grace periods; add CFcommon.arch
for arch-specific Kconfig options; print number of update types
in rcu_torture_write_types();
add rcutree.nohz_full_patience_delay testing to the TREE07
scenario; add a stall_cpu_repeat module parameter to test
repeated CPU stalls; add argument to limit number of CPUs a
guest OS can use in torture.sh;
rcustall.09.09.24a: Abbreviate RCU CPU stall warnings during CSD-lock
stalls; Allow dump_cpu_task() to be called without disabling
preemption; defer printing stall-warning backtrace when holding
rcu_node lock.
srcu.12.08.24a: Make SRCU gp seq wrap-around faster; add KCSAN checks
for concurrent updates to ->srcu_n_exp_nodelay and
->reschedule_count which are used in heuristics governing
auto-expediting of normal SRCU grace periods and
grace-period-state-machine delays; mark idle SRCU-barrier
callbacks to help identify stuck SRCU-barrier callback.
rcu.tasks.14.08.24a: Remove RCU Tasks Rude asynchronous APIs as they
are no longer used; stop testing RCU Tasks Rude asynchronous
APIs; fix access to non-existent percpu regions; check
processor-ID assumptions during chosen CPU calculation for
callback enqueuing; update description of rtp->tasks_gp_seq
grace-period sequence number; add rcu_barrier_cb_is_done()
to identify whether a given rcu_barrier callback is stuck;
mark idle Tasks-RCU-barrier callbacks; add
*torture_stats_print() functions to print detailed
diagnostics for Tasks-RCU variants; capture start time of
rcu_barrier_tasks*() operation to help distinguish a hung
barrier operation from a long series of barrier operations.
rcu_scaling_tests.15.08.24a:
refscale: Add a TINY scenario to support tests of Tiny RCU
and Tiny SRCU; Optimize process_durations() operation;
rcuscale: Dump stacks of stalled rcu_scale_writer() instances;
dump grace-period statistics when rcu_scale_writer() stalls;
mark idle RCU-barrier callbacks to identify stuck RCU-barrier
callbacks; print detailed grace-period and barrier diagnostics
on rcu_scale_writer() hangs for Tasks-RCU variants; warn if
async module parameter is specified for RCU implementations
that do not have async primitives such as RCU Tasks Rude;
make all writer tasks report upon hang; tolerate repeated
GFP_KERNEL failure in rcu_scale_writer(); use special allocator
for rcu_scale_writer(); NULL out top-level pointers to heap
memory to avoid double-free bugs on modprobe failures; maintain
per-task instead of per-CPU callbacks count to avoid any issues
with migration of either tasks or callbacks; constify struct
ref_scale_ops.
fixes.12.08.24a: Use system_unbound_wq for kfree_rcu work to avoid
disturbing isolated CPUs.
misc.11.08.24a: Warn on unexpected rcu_state.srs_done_tail state;
Better define "atomic" for list_replace_rcu() and
hlist_replace_rcu() routines; annotate struct
kvfree_rcu_bulk_data with __counted_by().
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQSi2tPIQIc2VEtjarIAHS7/6Z0wpQUCZt8+8wAKCRAAHS7/6Z0w
pTqoAPwPN//tlEoJx2PRs6t0q+nD1YNvnZawPaRmdzgdM8zJogD+PiSN+XhqRr80
jzyvMDU4Aa0wjUNP3XsCoaCxo7L/lQk=
=bZ9z
-----END PGP SIGNATURE-----
Merge tag 'rcu.release.v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux
Pull RCU updates from Neeraj Upadhyay:
"Context tracking:
- rename context tracking state related symbols and remove references
to "dynticks" in various context tracking state variables and
related helpers
- force context_tracking_enabled_this_cpu() to be inlined to avoid
leaving a noinstr section
CSD lock:
- enhance CSD-lock diagnostic reports
- add an API to provide an indication of ongoing CSD-lock stall
nocb:
- update and simplify RCU nocb code to handle (de-)offloading of
callbacks only for offline CPUs
- fix RT throttling hrtimer being armed from offline CPU
rcutorture:
- remove redundant rcu_torture_ops get_gp_completed fields
- add SRCU ->same_gp_state and ->get_comp_state functions
- add generic test for NUM_ACTIVE_*RCU_POLL* for testing RCU and SRCU
polled grace periods
- add CFcommon.arch for arch-specific Kconfig options
- print number of update types in rcu_torture_write_types()
- add rcutree.nohz_full_patience_delay testing to the TREE07 scenario
- add a stall_cpu_repeat module parameter to test repeated CPU stalls
- add argument to limit number of CPUs a guest OS can use in
torture.sh
rcustall:
- abbreviate RCU CPU stall warnings during CSD-lock stalls
- Allow dump_cpu_task() to be called without disabling preemption
- defer printing stall-warning backtrace when holding rcu_node lock
srcu:
- make SRCU gp seq wrap-around faster
- add KCSAN checks for concurrent updates to ->srcu_n_exp_nodelay and
->reschedule_count which are used in heuristics governing
auto-expediting of normal SRCU grace periods and
grace-period-state-machine delays
- mark idle SRCU-barrier callbacks to help identify stuck
SRCU-barrier callback
rcu tasks:
- remove RCU Tasks Rude asynchronous APIs as they are no longer used
- stop testing RCU Tasks Rude asynchronous APIs
- fix access to non-existent percpu regions
- check processor-ID assumptions during chosen CPU calculation for
callback enqueuing
- update description of rtp->tasks_gp_seq grace-period sequence
number
- add rcu_barrier_cb_is_done() to identify whether a given
rcu_barrier callback is stuck
- mark idle Tasks-RCU-barrier callbacks
- add *torture_stats_print() functions to print detailed diagnostics
for Tasks-RCU variants
- capture start time of rcu_barrier_tasks*() operation to help
distinguish a hung barrier operation from a long series of barrier
operations
refscale:
- add a TINY scenario to support tests of Tiny RCU and Tiny
SRCU
- optimize process_durations() operation
rcuscale:
- dump stacks of stalled rcu_scale_writer() instances and
grace-period statistics when rcu_scale_writer() stalls
- mark idle RCU-barrier callbacks to identify stuck RCU-barrier
callbacks
- print detailed grace-period and barrier diagnostics on
rcu_scale_writer() hangs for Tasks-RCU variants
- warn if async module parameter is specified for RCU implementations
that do not have async primitives such as RCU Tasks Rude
- make all writer tasks report upon hang
- tolerate repeated GFP_KERNEL failure in rcu_scale_writer()
- use special allocator for rcu_scale_writer()
- NULL out top-level pointers to heap memory to avoid double-free
bugs on modprobe failures
- maintain per-task instead of per-CPU callbacks count to avoid any
issues with migration of either tasks or callbacks
- constify struct ref_scale_ops
Fixes:
- use system_unbound_wq for kfree_rcu work to avoid disturbing
isolated CPUs
Misc:
- warn on unexpected rcu_state.srs_done_tail state
- better define "atomic" for list_replace_rcu() and
hlist_replace_rcu() routines
- annotate struct kvfree_rcu_bulk_data with __counted_by()"
* tag 'rcu.release.v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (90 commits)
rcu: Defer printing stall-warning backtrace when holding rcu_node lock
rcu/nocb: Remove superfluous memory barrier after bypass enqueue
rcu/nocb: Conditionally wake up rcuo if not already waiting on GP
rcu/nocb: Fix RT throttling hrtimer armed from offline CPU
rcu/nocb: Simplify (de-)offloading state machine
context_tracking: Tag context_tracking_enabled_this_cpu() __always_inline
context_tracking, rcu: Rename rcu_dyntick trace event into rcu_watching
rcu: Update stray documentation references to rcu_dynticks_eqs_{enter, exit}()
rcu: Rename rcu_momentary_dyntick_idle() into rcu_momentary_eqs()
rcu: Rename rcu_implicit_dynticks_qs() into rcu_watching_snap_recheck()
rcu: Rename dyntick_save_progress_counter() into rcu_watching_snap_save()
rcu: Rename struct rcu_data .exp_dynticks_snap into .exp_watching_snap
rcu: Rename struct rcu_data .dynticks_snap into .watching_snap
rcu: Rename rcu_dynticks_zero_in_eqs() into rcu_watching_zero_in_eqs()
rcu: Rename rcu_dynticks_in_eqs_since() into rcu_watching_snap_stopped_since()
rcu: Rename rcu_dynticks_in_eqs() into rcu_watching_snap_in_eqs()
rcu: Rename rcu_dynticks_eqs_online() into rcu_watching_online()
context_tracking, rcu: Rename rcu_dynticks_curr_cpu_in_eqs() into rcu_is_watching_curr_cpu()
context_tracking, rcu: Rename rcu_dynticks_task*() into rcu_task*()
refscale: Constify struct ref_scale_ops
...
Lonial found an issue that despite user- and BPF-side frozen BPF map
(like in case of .rodata), it was still possible to write into it from
a BPF program side through specific helpers having ARG_PTR_TO_{LONG,INT}
as arguments.
In check_func_arg() when the argument is as mentioned, the meta->raw_mode
is never set. Later, check_helper_mem_access(), under the case of
PTR_TO_MAP_VALUE as register base type, it assumes BPF_READ for the
subsequent call to check_map_access_type() and given the BPF map is
read-only it succeeds.
The helpers really need to be annotated as ARG_PTR_TO_{LONG,INT} | MEM_UNINIT
when results are written into them as opposed to read out of them. The
latter indicates that it's okay to pass a pointer to uninitialized memory
as the memory is written to anyway.
However, ARG_PTR_TO_{LONG,INT} is a special case of ARG_PTR_TO_FIXED_SIZE_MEM
just with additional alignment requirement. So it is better to just get
rid of the ARG_PTR_TO_{LONG,INT} special cases altogether and reuse the
fixed size memory types. For this, add MEM_ALIGNED to additionally ensure
alignment given these helpers write directly into the args via *<ptr> = val.
The .arg*_size has been initialized reflecting the actual sizeof(*<ptr>).
MEM_ALIGNED can only be used in combination with MEM_FIXED_SIZE annotated
argument types, since in !MEM_FIXED_SIZE cases the verifier does not know
the buffer size a priori and therefore cannot blindly write *<ptr> = val.
Fixes: 57c3bb725a ("bpf: Introduce ARG_PTR_TO_{INT,LONG} arg types")
Reported-by: Lonial Con <kongln9170@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://lore.kernel.org/r/20240913191754.13290-3-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Salvatore Benedetto reported an issue that when doing syscall tracepoint
tracing the kernel stack is empty. For example, using the following
command line
bpftrace -e 'tracepoint:syscalls:sys_enter_read { print("Kernel Stack\n"); print(kstack()); }'
bpftrace -e 'tracepoint:syscalls:sys_exit_read { print("Kernel Stack\n"); print(kstack()); }'
the output for both commands is
===
Kernel Stack
===
Further analysis shows that pt_regs used for bpf syscall tracepoint
tracing is from the one constructed during user->kernel transition.
The call stack looks like
perf_syscall_enter+0x88/0x7c0
trace_sys_enter+0x41/0x80
syscall_trace_enter+0x100/0x160
do_syscall_64+0x38/0xf0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The ip address stored in pt_regs is from user space hence no kernel
stack is printed.
To fix the issue, kernel address from pt_regs is required.
In kernel repo, there are already a few cases like this. For example,
in kernel/trace/bpf_trace.c, several perf_fetch_caller_regs(fake_regs_ptr)
instances are used to supply ip address or use ip address to construct
call stack.
Instead of allocate fake_regs in the stack which may consume
a lot of bytes, the function perf_trace_buf_alloc() in
perf_syscall_{enter, exit}() is leveraged to create fake_regs,
which will be passed to perf_call_bpf_{enter,exit}().
For the above bpftrace script, I got the following output with this patch:
for tracepoint:syscalls:sys_enter_read
===
Kernel Stack
syscall_trace_enter+407
syscall_trace_enter+407
do_syscall_64+74
entry_SYSCALL_64_after_hwframe+75
===
and for tracepoint:syscalls:sys_exit_read
===
Kernel Stack
syscall_exit_work+185
syscall_exit_work+185
syscall_exit_to_user_mode+305
do_syscall_64+118
entry_SYSCALL_64_after_hwframe+75
===
Reported-by: Salvatore Benedetto <salvabenedetto@meta.com>
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240910214037.3663272-1-yonghong.song@linux.dev
Add sleepable implementations of bpf_get_stack() and
bpf_get_task_stack() helpers and allow them to be used from sleepable
BPF program (e.g., sleepable uprobes).
Note, the stack trace IPs capturing itself is not sleepable (that would
need to be a separate project), only build ID fetching is sleepable and
thus more reliable, as it will wait for data to be paged in, if
necessary. For that we make use of sleepable build_id_parse()
implementation.
Now that build ID related internals in kernel/bpf/stackmap.c can be used
both in sleepable and non-sleepable contexts, we need to add additional
rcu_read_lock()/rcu_read_unlock() protection around fetching
perf_callchain_entry, but with the refactoring in previous commit it's
now pretty straightforward. We make sure to do rcu_read_unlock (in
sleepable mode only) right before stack_map_get_build_id_offset() call
which can sleep. By that time we don't have any more use of
perf_callchain_entry.
Note, bpf_get_task_stack() will fail for user mode if task != current.
And for kernel mode build ID are irrelevant. So in that sense adding
sleepable bpf_get_task_stack() implementation is a no-op. It feel right
to wire this up for symmetry and completeness, but I'm open to just
dropping it until we support `user && crosstask` condition.
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-10-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
A helper function defined but not used. This, in particular,
prevents kernel builds with clang, `make W=1` and CONFIG_WERROR=y:
kernel/trace/trace.c:2229:19: error: unused function 'run_tracer_selftest' [-Werror,-Wunused-function]
2229 | static inline int run_tracer_selftest(struct tracer *type)
| ^~~~~~~~~~~~~~~~~~~
Fix this by dropping unused functions.
See also commit 6863f5643d ("kbuild: allow Clang to find unused static
inline functions for W=1 build").
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/20240909105314.928302-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
To fix some critical section races, the interface_lock was added to a few
locations. One of those locations was above where the interface_lock was
declared, so the declaration was moved up before that usage.
Unfortunately, where it was placed was inside a CONFIG_TIMERLAT_TRACER
ifdef block. As the interface_lock is used outside that config, this broke
the build when CONFIG_OSNOISE_TRACER was enabled but
CONFIG_TIMERLAT_TRACER was not.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Helena Anna" <helena.anna.dubel@intel.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Link: https://lore.kernel.org/20240909103231.23a289e2@gandalf.local.home
Fixes: e6a53481da ("tracing/timerlat: Only clear timer if a kthread exists")
Reported-by: "Bityutskiy, Artem" <artem.bityutskiy@intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Uprobe multi link does its own process (thread leader) filtering before
running the bpf program by comparing task's vm pointers.
But as Oleg pointed out there can be processes sharing the vm (CLONE_VM),
so we can't just compare task->vm pointers, but instead we need to use
same_thread_group call.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/bpf/20240905115124.1503998-2-jolsa@kernel.org
The timerlat interface will get and put the task that is part of the
"kthread" field of the osn_var to keep it around until all references are
released. But here's a race in the "stop_kthread()" code that will call
put_task_struct() on the kthread if it is not a kernel thread. This can
race with the releasing of the references to that task struct and the
put_task_struct() can be called twice when it should have been called just
once.
Take the interface_lock() in stop_kthread() to synchronize this change.
But to do so, the function stop_per_cpu_kthreads() needs to change the
loop from for_each_online_cpu() to for_each_possible_cpu() and remove the
cpu_read_lock(), as the interface_lock can not be taken while the cpu
locks are held. The only side effect of this change is that it may do some
extra work, as the per_cpu variables of the offline CPUs would not be set
anyway, and would simply be skipped in the loop.
Remove unneeded "return;" in stop_kthread().
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20240905113359.2b934242@gandalf.local.home
Fixes: e88ed227f6 ("tracing/timerlat: Add user-space interface")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The timerlat tracer can use user space threads to check for osnoise and
timer latency. If the program using this is killed via a SIGTERM, the
threads are shutdown one at a time and another tracing instance can start
up resetting the threads before they are fully closed. That causes the
hrtimer assigned to the kthread to be shutdown and freed twice when the
dying thread finally closes the file descriptors, causing a use-after-free
bug.
Only cancel the hrtimer if the associated thread is still around. Also add
the interface_lock around the resetting of the tlat_var->kthread.
Note, this is just a quick fix that can be backported to stable. A real
fix is to have a better synchronization between the shutdown of old
threads and the starting of new ones.
Link: https://lore.kernel.org/all/20240820130001.124768-1-tglozar@redhat.com/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20240905085330.45985730@gandalf.local.home
Fixes: e88ed227f6 ("tracing/timerlat: Add user-space interface")
Reported-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The start_kthread() and stop_thread() code was not always called with the
interface_lock held. This means that the kthread variable could be
unexpectedly changed causing the kthread_stop() to be called on it when it
should not have been, leading to:
while true; do
rtla timerlat top -u -q & PID=$!;
sleep 5;
kill -INT $PID;
sleep 0.001;
kill -TERM $PID;
wait $PID;
done
Causing the following OOPS:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 5 UID: 0 PID: 885 Comm: timerlatu/5 Not tainted 6.11.0-rc4-test-00002-gbc754cc76d1b-dirty #125 a533010b71dab205ad2f507188ce8c82203b0254
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:hrtimer_active+0x58/0x300
Code: 48 c1 ee 03 41 54 48 01 d1 48 01 d6 55 53 48 83 ec 20 80 39 00 0f 85 30 02 00 00 49 8b 6f 30 4c 8d 75 10 4c 89 f0 48 c1 e8 03 <0f> b6 3c 10 4c 89 f0 83 e0 07 83 c0 03 40 38 f8 7c 09 40 84 ff 0f
RSP: 0018:ffff88811d97f940 EFLAGS: 00010202
RAX: 0000000000000002 RBX: ffff88823c6b5b28 RCX: ffffed10478d6b6b
RDX: dffffc0000000000 RSI: ffffed10478d6b6c RDI: ffff88823c6b5b28
RBP: 0000000000000000 R08: ffff88823c6b5b58 R09: ffff88823c6b5b60
R10: ffff88811d97f957 R11: 0000000000000010 R12: 00000000000a801d
R13: ffff88810d8b35d8 R14: 0000000000000010 R15: ffff88823c6b5b28
FS: 0000000000000000(0000) GS:ffff88823c680000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561858ad7258 CR3: 000000007729e001 CR4: 0000000000170ef0
Call Trace:
<TASK>
? die_addr+0x40/0xa0
? exc_general_protection+0x154/0x230
? asm_exc_general_protection+0x26/0x30
? hrtimer_active+0x58/0x300
? __pfx_mutex_lock+0x10/0x10
? __pfx_locks_remove_file+0x10/0x10
hrtimer_cancel+0x15/0x40
timerlat_fd_release+0x8e/0x1f0
? security_file_release+0x43/0x80
__fput+0x372/0xb10
task_work_run+0x11e/0x1f0
? _raw_spin_lock+0x85/0xe0
? __pfx_task_work_run+0x10/0x10
? poison_slab_object+0x109/0x170
? do_exit+0x7a0/0x24b0
do_exit+0x7bd/0x24b0
? __pfx_migrate_enable+0x10/0x10
? __pfx_do_exit+0x10/0x10
? __pfx_read_tsc+0x10/0x10
? ktime_get+0x64/0x140
? _raw_spin_lock_irq+0x86/0xe0
do_group_exit+0xb0/0x220
get_signal+0x17ba/0x1b50
? vfs_read+0x179/0xa40
? timerlat_fd_read+0x30b/0x9d0
? __pfx_get_signal+0x10/0x10
? __pfx_timerlat_fd_read+0x10/0x10
arch_do_signal_or_restart+0x8c/0x570
? __pfx_arch_do_signal_or_restart+0x10/0x10
? vfs_read+0x179/0xa40
? ksys_read+0xfe/0x1d0
? __pfx_ksys_read+0x10/0x10
syscall_exit_to_user_mode+0xbc/0x130
do_syscall_64+0x74/0x110
? __pfx___rseq_handle_notify_resume+0x10/0x10
? __pfx_ksys_read+0x10/0x10
? fpregs_restore_userregs+0xdb/0x1e0
? fpregs_restore_userregs+0xdb/0x1e0
? syscall_exit_to_user_mode+0x116/0x130
? do_syscall_64+0x74/0x110
? do_syscall_64+0x74/0x110
? do_syscall_64+0x74/0x110
entry_SYSCALL_64_after_hwframe+0x71/0x79
RIP: 0033:0x7ff0070eca9c
Code: Unable to access opcode bytes at 0x7ff0070eca72.
RSP: 002b:00007ff006dff8c0 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00007ff0070eca9c
RDX: 0000000000000400 RSI: 00007ff006dff9a0 RDI: 0000000000000003
RBP: 00007ff006dffde0 R08: 0000000000000000 R09: 00007ff000000ba0
R10: 00007ff007004b08 R11: 0000000000000246 R12: 0000000000000003
R13: 00007ff006dff9a0 R14: 0000000000000007 R15: 0000000000000008
</TASK>
Modules linked in: snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec snd_hwdep snd_hda_core
---[ end trace 0000000000000000 ]---
This is because it would mistakenly call kthread_stop() on a user space
thread making it "exit" before it actually exits.
Since kthreads are created based on global behavior, use a cpumask to know
when kthreads are running and that they need to be shutdown before
proceeding to do new work.
Link: https://lore.kernel.org/all/20240820130001.124768-1-tglozar@redhat.com/
This was debugged by using the persistent ring buffer:
Link: https://lore.kernel.org/all/20240823013902.135036960@goodmis.org/
Note, locking was originally used to fix this, but that proved to cause too
many deadlocks to work around:
https://lore.kernel.org/linux-trace-kernel/20240823102816.5e55753b@gandalf.local.home/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20240904103428.08efdf4c@gandalf.local.home
Fixes: e88ed227f6 ("tracing/timerlat: Add user-space interface")
Reported-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
With uprobe_unregister() having grown a synchronize_srcu(), it becomes
fairly slow to call. Esp. since both users of this API call it in a
loop.
Peel off the sync_srcu() and do it once, after the loop.
We also need to add uprobe_unregister_sync() into uprobe_register()'s
error handling path, as we need to be careful about returning to the
caller before we have a guarantee that partially attached consumer won't
be called anymore. This is an unlikely slow path and this should be
totally fine to be slow in the case of a failed attach.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Co-developed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20240903174603.3554182-6-andrii@kernel.org
It serves no purpose beyond adding unnecessray argument passed to the
filter callback. Just get rid of it, no one is actually using it.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20240903174603.3554182-4-andrii@kernel.org
In __tracing_open(), when max latency tracers took place on the cpu,
the time start of its buffer would be updated, then event entries with
timestamps being earlier than start of the buffer would be skipped
(see tracing_iter_reset()).
Softlockup will occur if the kernel is non-preemptible and too many
entries were skipped in the loop that reset every cpu buffer, so add
cond_resched() to avoid it.
Cc: stable@vger.kernel.org
Fixes: 2f26ebd549 ("tracing: use timestamp to determine start of latency traces")
Link: https://lore.kernel.org/20240827124654.3817443-1-zhengyejian@huaweicloud.com
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Zheng Yejian <zhengyejian@huaweicloud.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a option "trace_printk_dest" that will make the tracing instance the
location that trace_printk() will go to. This is useful if the
trace_printk or one of the top level tracers is too noisy and there's a
need to separate the two. Then an instance can be created, the
trace_printk can be set to go there instead, where it will not be lost in
the noise of the top level tracer.
Note, only one instance can be the destination of trace_printk at a time.
If an instance sets this flag, the instance that had it set will have it
cleared. There is always one instance that has this set. By default, that
is the top instance. This flag cannot be cleared from the top instance.
Doing so will result in an -EINVAL. The only way this flag can be cleared
from the top instance is by another instance setting it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineeth Pillai <vineeth@bitbyteword.org>
Cc: Beau Belgrave <beaub@linux.microsoft.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Ross Zwisler <zwisler@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Aring <aahringo@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Jonathan Corbet" <corbet@lwn.net>
Link: https://lore.kernel.org/20240823014019.545459018@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
If the persistent boot mapped ring buffer is used for trace_printk(),
force it to not use the binary versions. trace_printk() by default uses
bin_printf() that only saves the pointer to the format and not the format
itself inside the ring buffer. But for a persistent buffer that is read
after reboot, the pointers to the format strings may not be the same, or
worse, not even exist! Instead, just force the more robust, but slower,
version that does the formatting before saving into the ring buffer.
The boot mapped buffer can now be used for trace_printk and friends!
Using the trace_printk() and the persistent buffer was used to debug the
issue with the osnoise tracer:
Link: https://lore.kernel.org/all/20240822103443.6a6ae051@gandalf.local.home/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineeth Pillai <vineeth@bitbyteword.org>
Cc: Beau Belgrave <beaub@linux.microsoft.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Ross Zwisler <zwisler@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Aring <aahringo@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Jonathan Corbet" <corbet@lwn.net>
Link: https://lore.kernel.org/20240823014019.386925800@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently, trace_printk() just goes to the top level ring buffer. But
there may be times that it should go to one of the instances created by
the kernel command line.
Add a new trace_instance flag: traceprintk (also can use "printk" or
"trace_printk" as people tend to forget the actual flag name).
trace_instance=foo^traceprintk
Will assign the trace_printk to this buffer at boot up.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineeth Pillai <vineeth@bitbyteword.org>
Cc: Beau Belgrave <beaub@linux.microsoft.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Ross Zwisler <zwisler@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Aring <aahringo@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Jonathan Corbet" <corbet@lwn.net>
Link: https://lore.kernel.org/20240823014019.226694946@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a "flags" delimiter (^) to the "trace_instance" kernel command line
parameter, and add the "traceoff" flag. The format is:
trace_instance=<name>[^<flag1>[^<flag2>]][@<memory>][,<events>]
The code allows for more than one flag to be added, but currently only
"traceoff" is done so.
The motivation for this change came from debugging with the persistent
ring buffer and having trace_printk() writing to it. The trace_printk
calls are always enabled, and the boot after the crash was having the
unwanted trace_printks from the current boot inject into the ring buffer
with the trace_printks of the crash kernel, making the output very
confusing.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineeth Pillai <vineeth@bitbyteword.org>
Cc: Beau Belgrave <beaub@linux.microsoft.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Ross Zwisler <zwisler@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Aring <aahringo@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Jonathan Corbet" <corbet@lwn.net>
Link: https://lore.kernel.org/20240823014019.053229958@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Previously, the mapped ring-buffer layout caused misalignment between
the meta-page and sub-buffers when the sub-buffer size was not a
multiple of PAGE_SIZE. This prevented hardware with larger TLB entries
from utilizing them effectively.
Add a padding with the zero-page between the meta-page and sub-buffers.
Also update the ring-buffer map_test to verify that padding.
Link: https://lore.kernel.org/20240628104611.1443542-1-vdonnefort@google.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a magic number as well as save the struct size of the ring_buffer_meta
structure in the meta data to also use as validation. Updating the magic
number could be used to force a invalidation between kernel versions, and
saving the structure size is also a good method to make sure the content
is what is expected.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20240815115032.0c197b32@rorschach.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The text and data address is saved in the meta data so that it can be used
to know the delta of the text and data addresses of the last boot compared
to the text and data addresses of the current boot. The delta is used to
convert function pointer entries in the ring buffer to something that can
be used by kallsyms (note this only works for built-in functions).
But the saved addresses get reset on boot up. If the buffer is not used
and there's another reboot, then the saved text and data addresses will be
of the last boot and not that of the boot that created the content in the
ring buffer.
To get an idea of the issue:
# trace-cmd start -B boot_mapped -p function
# reboot
# trace-cmd show -B boot_mapped | tail
<...>-1 [000] d..1. 461.983243: native_apic_msr_write <-native_kick_ap
<...>-1 [000] d..1. 461.983244: __pfx_native_apic_msr_eoi <-native_kick_ap
<...>-1 [000] d..1. 461.983244: reserve_irq_vector_locked <-native_kick_ap
<...>-1 [000] d..1. 461.983262: branch_emulate_op <-native_kick_ap
<...>-1 [000] d..1. 461.983262: __ia32_sys_ia32_pread64 <-native_kick_ap
<...>-1 [000] d..1. 461.983263: native_kick_ap <-__smpboot_create_thread
<...>-1 [000] d..1. 461.983263: store_cache_disable <-native_kick_ap
<...>-1 [000] d..1. 461.983279: acpi_power_off_prepare <-native_kick_ap
<...>-1 [000] d..1. 461.983280: __pfx_acpi_ns_delete_node <-acpi_suspend_enter
<...>-1 [000] d..1. 461.983280: __pfx_acpi_os_release_lock <-acpi_suspend_enter
# reboot
# trace-cmd show -B boot_mapped |tail
<...>-1 [000] d..1. 461.983243: 0xffffffffa9669220 <-0xffffffffa965f3db
<...>-1 [000] d..1. 461.983244: 0xffffffffa96690f0 <-0xffffffffa965f3db
<...>-1 [000] d..1. 461.983244: 0xffffffffa9663fa0 <-0xffffffffa965f3db
<...>-1 [000] d..1. 461.983262: 0xffffffffa9672e80 <-0xffffffffa965f3e0
<...>-1 [000] d..1. 461.983262: 0xffffffffa962b940 <-0xffffffffa965f3ec
<...>-1 [000] d..1. 461.983263: 0xffffffffa965f540 <-0xffffffffa96e1362
<...>-1 [000] d..1. 461.983263: 0xffffffffa963c940 <-0xffffffffa965f55b
<...>-1 [000] d..1. 461.983279: 0xffffffffa9ee30c0 <-0xffffffffa965f59b
<...>-1 [000] d..1. 461.983280: 0xffffffffa9f16c10 <-0xffffffffa9ee3157
<...>-1 [000] d..1. 461.983280: 0xffffffffa9ee02e0 <-0xffffffffa9ee3157
By not updating the saved text and data addresses in the meta data at
every boot up and only updating them when the buffer is reset, it
allows multiple boots to see the same data.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20240815113629.0dc90af8@rorschach.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Since the register_ftrace_graph() assigns a new fgraph_ops to
fgraph_array before registring it by ftrace_startup_subops(), the new
fgraph_ops can be used in function_graph_enter().
In most cases, it is still OK because those fgraph_ops's hashtable is
already initialized by ftrace_set_filter*() etc.
But if a user registers a new fgraph_ops which does not initialize the
hash list, ftrace_ops_test() in function_graph_enter() causes a NULL
pointer dereference BUG because fgraph_ops->ops.func_hash is NULL.
This can be reproduced by the below commands because function profiler's
fgraph_ops does not initialize the hash list;
# cd /sys/kernel/tracing
# echo function_graph > current_tracer
# echo 1 > function_profile_enabled
To fix this problem, add a new fgraph_ops to fgraph_array after
ftrace_startup_subops(). Thus, until the new fgraph_ops is initialized,
we will see fgraph_stub on the corresponding fgraph_array entry.
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: bpf <bpf@vger.kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/172398528350.293426.8347220120333730248.stgit@devnote2
Fixes: c132be2c4f ("function_graph: Have the instances use their own ftrace_ops for filtering")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The helper bpf_current_task_under_cgroup() currently is only allowed for
tracing programs, allow its usage also in the BPF_CGROUP_* program types.
Move the code from kernel/trace/bpf_trace.c to kernel/bpf/helpers.c,
so it compiles also without CONFIG_BPF_EVENTS.
This will be used in systemd-networkd to monitor the sysctl writes,
and filter it's own writes from others:
https://github.com/systemd/systemd/pull/32212
Signed-off-by: Matteo Croce <teknoraver@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240819162805.78235-3-technoboy85@gmail.com
The context_tracking.state RCU_DYNTICKS subvariable has been renamed to
RCU_WATCHING, replace "dyntick_idle" into "eqs" to drop the dyntick
reference.
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Allow boot instances to use memory reserved by the reserve_mem boot
option.
reserve_mem=12M:4096:trace trace_instance=boot_mapped@trace
The above will allocate 12 megs with 4096 alignment and label it "trace".
The second parameter will create a "boot_mapped" instance and use the
memory reserved and labeled as "trace" as the memory for the ring buffer.
That will create an instance called "boot_mapped":
/sys/kernel/tracing/instances/boot_mapped
Note, because the ring buffer is using a defined memory ranged, it will
act just like a memory mapped ring buffer. It will not have a snapshot
buffer, as it can't swap out the buffer. The snapshot files as well as any
tracers that uses a snapshot will not be present in the boot_mapped
instance.
Also note that reserve_mem is not reliable in acquiring the same physical
memory at each soft reboot. It is possible that KALSR could map the kernel
at the previous boot memory location forcing the reserve_mem to return a
different memory location. In this case, the previous ring buffer will be
lost.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ross Zwisler <zwisler@google.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20240815082811.669f7d8c@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The mapping of the ring buffer to memory allocated at boot up will also
expose a "last_boot_info" to help tooling to read the raw data from the
last boot. As instances that have their ring buffer mapped to fixed
memory cannot perform snapshots, they can either have the "snapshot" file
or the "last_boot_info" file, but not both.
The code that added the "last_boot_info" file failed to notice that the
"snapshot" creation was inside a "#ifdef CONFIG_TRACER_SNAPSHOT" and
incorrectly placed the creation of the "last_boot_info" file within the
ifdef block. Not only does it cause a warning when CONFIG_TRACER_SNAPSHOT
is not enabled, it also incorrectly prevents the file from appearing.
Link: https://lore.kernel.org/all/20240719102640.718554-1-arnd@kernel.org/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reported-by: Arnd Bergmann <arnd@kernel.org>
Link: https://lore.kernel.org/20240719101312.3d4ac707@rorschach.local.home
Fixes: 7a1d1e4b96 ("tracing/ring-buffer: Add last_boot_info file to boot instance")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAma5LLIeHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGwUAIAJNwbkdgTIqEsyBU
wsFcXGaFSsGJNbTulINJb34jl2gD2yr4pmnnrA0NePW1TUKOnx169hNMF8NWbr/A
0cHIREV9cyfnm/kzAcnHn7cWLSmsKd+x3TnCbCyodDZQDJzdLmw3LQG+4dTNJbw1
WtJO/EoaU4qaydW2VxtApw54sirq5bopZz7rpcRapA1afzbA2TUDbnnuEWjm9KCF
5K+RZTJZA/xI9gqEwJB+/p5FglW4n/T3xcDwaQp5uFsDskgV5e1AUrRLM+icTsem
0Egrs8Ca2Vp4oBM+r9miCSwjRu04jLKyuu20p7AN8zXLyN7WGAjduS15Dv+aHRZ/
9XABZs0=
=/T17
-----END PGP SIGNATURE-----
Merge tag 'v6.11-rc3' into trace/ring-buffer/core
The "reserve_mem" kernel command line parameter has been pulled into
v6.11. Merge the latest -rc3 to allow the persistent ring buffer memory to
be able to be mapped at the address specified by the "reserve_mem" command
line parameter.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When running the following:
# cd /sys/kernel/tracing/
# echo 1 > events/sched/sched_waking/enable
# echo 1 > events/sched/sched_switch/enable
# echo 0 > tracing_on
# dd if=per_cpu/cpu0/trace_pipe_raw of=/tmp/raw0.dat
The dd task would get stuck in an infinite loop in the kernel. What would
happen is the following:
When ring_buffer_read_page() returns -1 (no data) then a check is made to
see if the buffer is empty (as happens when the page is not full), it will
call wait_on_pipe() to wait until the ring buffer has data. When it is it
will try again to read data (unless O_NONBLOCK is set).
The issue happens when there's a reader and the file descriptor is closed.
The wait_on_pipe() will return when that is the case. But this loop will
continue to try again and wait_on_pipe() will again return immediately and
the loop will continue and never stop.
Simply check if the file was closed before looping and exit out if it is.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20240808235730.78bf63e5@rorschach.local.home
Fixes: 2aa043a55b ("tracing/ring-buffer: Fix wait_on_pipe() race")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Because ring_buffer_nr_pages() is not an inline function and user accesses
buffer->buffers[cpu]->nr_pages directly, the function ring_buffer_nr_pages
is removed.
Signed-off-by: Jianhui Zhou <912460177@qq.com>
Link: https://lore.kernel.org/tencent_F4A7E9AB337F44E0F4B858D07D19EF460708@qq.com
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
"tracing_map->next_elt" in get_free_elt() is at risk of overflowing.
Once it overflows, new elements can still be inserted into the tracing_map
even though the maximum number of elements (`max_elts`) has been reached.
Continuing to insert elements after the overflow could result in the
tracing_map containing "tracing_map->max_size" elements, leaving no empty
entries.
If any attempt is made to insert an element into a full tracing_map using
`__tracing_map_insert()`, it will cause an infinite loop with preemption
disabled, leading to a CPU hang problem.
Fix this by preventing any further increments to "tracing_map->next_elt"
once it reaches "tracing_map->max_elt".
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 08d43a5fa0 ("tracing: Add lock-free tracing_map")
Co-developed-by: Cheng-Jui Wang <cheng-jui.wang@mediatek.com>
Link: https://lore.kernel.org/20240805055922.6277-1-Tze-nan.Wu@mediatek.com
Signed-off-by: Cheng-Jui Wang <cheng-jui.wang@mediatek.com>
Signed-off-by: Tze-nan Wu <Tze-nan.Wu@mediatek.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Instead of using an atomic counter for the trace_event_file reference
counter, use the refcount interface. It has various checks to make sure
the reference counting is correct, and will warn if it detects an error
(like refcount_inc() on '0').
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20240726144208.687cce24@rorschach.local.home
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When eventfs was introduced, special care had to be done to coordinate the
freeing of the file meta data with the files that are exposed to user
space. The file meta data would have a ref count that is set when the file
is created and would be decremented and freed after the last user that
opened the file closed it. When the file meta data was to be freed, it
would set a flag (EVENT_FILE_FL_FREED) to denote that the file is freed,
and any new references made (like new opens or reads) would fail as it is
marked freed. This allowed other meta data to be freed after this flag was
set (under the event_mutex).
All the files that were dynamically created in the events directory had a
pointer to the file meta data and would call event_release() when the last
reference to the user space file was closed. This would be the time that it
is safe to free the file meta data.
A shortcut was made for the "format" file. It's i_private would point to
the "call" entry directly and not point to the file's meta data. This is
because all format files are the same for the same "call", so it was
thought there was no reason to differentiate them. The other files
maintain state (like the "enable", "trigger", etc). But this meant if the
file were to disappear, the "format" file would be unaware of it.
This caused a race that could be trigger via the user_events test (that
would create dynamic events and free them), and running a loop that would
read the user_events format files:
In one console run:
# cd tools/testing/selftests/user_events
# while true; do ./ftrace_test; done
And in another console run:
# cd /sys/kernel/tracing/
# while true; do cat events/user_events/__test_event/format; done 2>/dev/null
With KASAN memory checking, it would trigger a use-after-free bug report
(which was a real bug). This was because the format file was not checking
the file's meta data flag "EVENT_FILE_FL_FREED", so it would access the
event that the file meta data pointed to after the event was freed.
After inspection, there are other locations that were found to not check
the EVENT_FILE_FL_FREED flag when accessing the trace_event_file. Add a
new helper function: event_file_file() that will make sure that the
event_mutex is held, and will return NULL if the trace_event_file has the
EVENT_FILE_FL_FREED flag set. Have the first reference of the struct file
pointer use event_file_file() and check for NULL. Later uses can still use
the event_file_data() helper function if the event_mutex is still held and
was not released since the event_file_file() call.
Link: https://lore.kernel.org/all/20240719204701.1605950-1-minipli@grsecurity.net/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Cc: Ilkka Naulapää <digirigawa@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Beau Belgrave <beaub@linux.microsoft.com>
Cc: Florian Fainelli <florian.fainelli@broadcom.com>
Cc: Alexey Makhalov <alexey.makhalov@broadcom.com>
Cc: Vasavi Sirnapalli <vasavi.sirnapalli@broadcom.com>
Link: https://lore.kernel.org/20240730110657.3b69d3c1@gandalf.local.home
Fixes: b63db58e2f ("eventfs/tracing: Add callback for release of an eventfs_inode")
Reported-by: Mathias Krause <minipli@grsecurity.net>
Tested-by: Mathias Krause <minipli@grsecurity.net>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
