linux/kernel
Linus Torvalds cb8a75eec0 ring-buffer updates for 7.3:
- Remove unneeded semicolon
 
   A macro ended with a semicolon that wasn't needed.
 
 - Fix freeing cpu_buffer extra subbuffer with order greater than zero
 
   When the cpu_buffer was being freed, its "free" page, was using
   free_page() to free it when it could be more than one page.
 
 - Hold the cpu_buffer lock when resizing the subbuffer
 
   The freeing of the "free" page of the cpu_buffer was done without locking.
   The order of the data was being saved and then the "free" page was set to
   NULL. But there is a race that the "free" page could have been updated
   between those two operations. Add locking around it to prevent the race.
 
 - Save the order of the data along with the data in the free page
 
   The cpu_buffer would store just the data portion of the subbuffer page in
   its descriptor. But it did not store the order of the data pages. The order
   was being saved in the global buffer descriptor. But this leads to races.
 
   Have the cpu_buffer save the subbuf data along with its metadata (which
   includes the order of the page) to make sure when it frees it, it frees
   the correct order along with it.
 
 - Remove the subbuf_size and use the order directly when needed
 
   Having a size field for the size of the subbufer along with its order
   allowed for races to have them get out of sync. Remove the subbuf_size and
   use the order from the subbuf meta data directly under locks.
 
   Use the subbuf_order for other calculations in the ring buffer.
 
 - Remove the useless "cpus" field of trace_buffer
 
   The code has been restructured and the "cpus" field is no longer used.
   Remove it.
 
 - Remove the "mapped" field of the ring buffer and use a helper function instead.
 
   The "mapped" field has become a bit overused and made the code come
   complex in using a counter for what is denoted as being mapped or not.
   There are other fields that are set when the ring buffer is considered
   mapped. Add a helper function to check those fields and use that instead
   of keeping track of a counter.
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Merge tag 'trace-ringbuffer-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull ring-buffer updates from Steven Rostedt:

 - Remove unneeded semicolon

   A macro ended with a semicolon that wasn't needed.

 - Fix freeing cpu_buffer extra subbuffer with order greater than zero

   When the cpu_buffer was being freed, its "free" page, was using
   free_page() to free it when it could be more than one page.

 - Hold the cpu_buffer lock when resizing the subbuffer

   The freeing of the "free" page of the cpu_buffer was done without
   locking. The order of the data was being saved and then the "free"
   page was set to NULL. But there is a race that the "free" page could
   have been updated between those two operations. Add locking around it
   to prevent the race.

 - Save the order of the data along with the data in the free page

   The cpu_buffer would store just the data portion of the subbuffer
   page in its descriptor. But it did not store the order of the data
   pages. The order was being saved in the global buffer descriptor. But
   this leads to races.

   Have the cpu_buffer save the subbuf data along with its metadata
   (which includes the order of the page) to make sure when it frees it,
   it frees the correct order along with it.

 - Remove the subbuf_size and use the order directly when needed

   Having a size field for the size of the subbufer along with its order
   allowed for races to have them get out of sync. Remove the
   subbuf_size and use the order from the subbuf meta data directly
   under locks.

   Use the subbuf_order for other calculations in the ring buffer.

 - Remove the useless "cpus" field of trace_buffer

   The code has been restructured and the "cpus" field is no longer
   used. Remove it.

 - Remove the "mapped" field of the ring buffer and use a helper
   function instead.

   The "mapped" field has become a bit overused and made the code come
   complex in using a counter for what is denoted as being mapped or
   not. There are other fields that are set when the ring buffer is
   considered mapped. Add a helper function to check those fields and
   use that instead of keeping track of a counter.

* tag 'trace-ringbuffer-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Remove ring_buffer_per_cpu::mapped
  ring-buffer: Remove trace_buffer::cpus
  ring-buffer: Dynamically calculate max_data_size
  ring-buffer: Fix subbuf resize race with ring_buffer_alloc_read_page()
  ring-buffer: Fix subbuf resize race with ring buffer readers
  ring-buffer: Make cpu_buffer::free_page a buffer_data_read_page
  ring-buffer: Hold cpu_buffer::lock when resizing a subbuf
  ring-buffer: Free cpu_buffer::free_page with subbuf_order
  ring-buffer: drop unneeded semicolon
2026-08-19 14:22:07 -07:00
..
bpf tracing updates for v7.3: 2026-08-19 14:06:14 -07:00
cgroup Merge branch 'sched/urgent' 2026-08-14 16:12:58 +02:00
configs slab: support for compiler-assisted type-based slab cache partitioning 2026-05-14 10:44:09 +02:00
debug kgdb: update outdated references to kgdb_wait() 2026-04-21 16:41:54 +01:00
dma dma-mapping updates for Linux 7.2: 2026-06-17 12:20:21 -07:00
entry entry: Rework trace_syscall_enter() 2026-07-20 20:38:40 +02:00
events Performance events updates for v7.3: 2026-08-18 12:31:07 -07:00
futex Futex updates: 2026-08-18 15:26:35 -07:00
gcov Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
irq Generic interrupt subsystem updates: 2026-08-18 15:19:50 -07:00
kcsan kcsan: test: Adjust "expect" allocation type for kmalloc_obj 2026-02-26 09:54:08 -08:00
livepatch Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
liveupdate Merge branch 'misc' into next 2026-08-04 10:51:49 +03:00
locking irq,spin_lock: Add counted interrupt disabling/enabling 2026-08-10 10:50:18 +02:00
module module: decompress: check return value of module_extend_max_pages() 2026-06-04 16:37:32 +00:00
power PM: sleep: Allow disabling DPM watchdog by default 2026-07-23 15:46:34 +02:00
printk printk: fix typos in comments 2026-06-02 15:36:06 +02:00
rcu Updates for the NOHZ subsystem: 2026-06-15 13:48:52 +05:30
sched Timers and timekeeping core updates: 2026-08-18 16:23:56 -07:00
time VDSO updates: 2026-08-18 16:56:25 -07:00
trace ring-buffer updates for 7.3: 2026-08-19 14:22:07 -07:00
unwind Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
.gitignore kheaders: rebuild kheaders_data.tar.xz when a file is modified within a minute 2025-06-24 20:30:37 +09:00
acct.c fs: move SB_I_USERNS_VISIBLE to FS_USERNS_MOUNT_RESTRICTED 2026-05-11 23:13:01 +02:00
async.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
audit_fsnotify.c audit: fix recursive locking deadlock in audit_dupe_exe() 2026-05-27 19:15:34 -04:00
audit_tree.c audit: use 'unsigned int' instead of 'unsigned' 2026-05-26 17:15:30 -04:00
audit_watch.c audit: fix recursive locking deadlock in audit_dupe_exe() 2026-05-27 19:15:34 -04:00
audit.c audit: fix potential integer overflow in audit_log_n_string() 2026-07-29 16:19:06 -04:00
audit.h audit: fix recursive locking deadlock in audit_dupe_exe() 2026-05-27 19:15:34 -04:00
auditfilter.c audit: fix potential use-after-free in audit_del_rule() 2026-07-29 16:19:06 -04:00
auditsc.c audit/stable-7.2 PR 20260615 2026-06-17 12:55:09 +01:00
backtracetest.c
bounds.c x86/asm: Remove ANNOTATE_DATA_SPECIAL usage 2025-12-03 16:53:19 +01:00
capability.c capability: Remove unused has_capability 2025-03-07 22:03:09 -06:00
cfi.c cfi: Move BPF CFI types and helpers to generic code 2025-07-31 18:23:53 -07:00
compat.c
configs.c
context_tracking.c context_tracking: Remove rcu_task_trace_heavyweight_{enter,exit}() 2026-01-01 16:39:46 +08:00
cpu_pm.c syscore: Pass context data to callbacks 2025-11-14 10:01:52 +01:00
cpu.c Misc CPU hotplug fixes: 2026-06-23 16:43:24 -07:00
crash_core_test.c crash: add KUnit tests for crash_exclude_mem_range 2025-09-13 17:32:55 -07:00
crash_core.c powerpc/kexec_file: Use crash_exclude_core_ranges() helper 2026-06-30 18:49:06 +03:00
crash_dump_dm_crypt.c crash_dump: release keyring reference at the correct time 2026-07-13 10:04:47 +03:00
crash_reserve.c kernel/crash: remove inclusion of crypto/sha1.h 2026-03-27 21:19:46 -07:00
cred.c exec_state: relocate dumpable information 2026-05-26 11:02:01 +02:00
delayacct.c delayacct: fix uapi timespec64 definition 2026-02-08 00:13:32 -08:00
dma.c
elfcorehdr.c
exec_domain.c
exec_state.c exec_state: relocate dumpable information 2026-05-26 11:02:01 +02:00
exit.c ipc-7.3-rc1.misc 2026-08-17 08:27:30 -07:00
exit.h
extable.c
fail_function.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
fork.c SMP core updates: 2026-08-18 15:29:53 -07:00
freezer.c freezer: Clarify that only cgroup1 freezer uses PM freezer 2025-10-30 20:10:27 +01:00
gen_kheaders.sh kheaders: make it possible to override TAR 2025-08-06 10:23:36 +09:00
groups.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
hung_task.c hung_task: explicitly report I/O wait state in log output 2026-03-27 21:19:40 -07:00
iomem.c mm/memremap: Pass down MEMREMAP_* flags to arch_memremap_wb() 2025-02-21 15:05:38 +01:00
irq_work.c irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT 2026-05-11 16:28:04 +02:00
jump_label.c jump_label: use ATOMIC_INIT() for initialization of .enabled 2026-03-16 13:16:48 +01:00
kallsyms_internal.h kallsyms: Get rid of kallsyms relative base 2026-01-22 15:58:22 -07:00
kallsyms_selftest.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kallsyms_selftest.h
kallsyms.c mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
kcmp.c fs: add real_fs to track task's actual fs_struct 2026-06-29 10:43:45 +02:00
Kconfig.freezer
Kconfig.hz kernel: Fix "select" wording on HZ_250 description 2025-02-21 09:20:30 +01:00
Kconfig.kexec liveupdate: kho: move to kernel/liveupdate 2025-11-27 14:24:33 -08:00
Kconfig.locks locking/qspinlock: Add contended_release tracepoint 2026-08-07 17:58:10 +02:00
Kconfig.preempt preempt: Introduce HAS_SEPARATE_PREEMPT_RESCHED_BITS 2026-08-10 10:50:19 +02:00
kcov.c kcov: use WRITE_ONCE() for selftest mode stores 2026-06-04 14:49:26 -07:00
kexec_core.c liveupdate: skip serialization for context-preserving kexec 2026-06-01 09:19:38 +03:00
kexec_elf.c kexec: initialize ELF lowest address to ULONG_MAX 2025-03-16 22:30:47 -07:00
kexec_file.c kexec_file: skip checksum verification when safe 2026-07-01 13:01:08 +03:00
kexec_internal.h kexec: enable CMA based contiguous allocation 2025-08-02 12:01:38 -07:00
kexec.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kheaders.c
kprobes.c kprobes: Remove unneeded warnings from __arm_kprobe_ftrace() 2026-03-13 23:15:26 +09:00
kstack_erase.c sysctl: remove __user qualifier from stack_erasing_sysctl buffer argument 2025-11-27 15:44:53 +01:00
ksyms_common.c
ksysfs.c kernel: ksysfs: initialize kernel_kobj earlier 2026-04-03 19:39:52 +02:00
kthread.c exec_state: relocate dumpable information 2026-05-26 11:02:01 +02:00
latencytop.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
Makefile exec: introduce struct task_exec_state 2026-05-26 11:02:01 +02:00
module_signature.c module: Give 'enum pkey_id_type' a more specific name 2026-03-24 21:42:37 +00:00
notifier.c
nscommon.c nsfs: tighten permission checks for ns iteration ioctls 2026-02-27 22:00:08 +01:00
nsproxy.c vfs-7.1-rc1.mount.v2 2026-04-14 19:59:25 -07:00
nstree.c nstree: tighten permission checks for listing 2026-02-27 22:00:11 +01:00
padata.c padata: Put CPU offline callback in ONLINE section to allow failure 2026-03-22 11:17:59 +09:00
panic.c bug/kunit: Core support for suppressing warning backtraces 2026-05-14 10:50:00 -06:00
params.c kernel: param: initialize module_kset in a pure_initcall 2026-06-08 23:27:56 +02:00
pid_namespace.c pid_namespace: allow opening pid_for_children before init was created 2026-03-20 14:44:26 +01:00
pid_sysctl.h treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
pid.c pid: reject allocations through dead ancestor pid namespaces 2026-08-12 12:56:30 +02:00
profile.c
ptrace.c exec_state: relocate dumpable information 2026-05-26 11:02:01 +02:00
range.c
reboot.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
regset.c
relay.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
resource_kunit.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
resource.c resource: Make resource_alignment() input const resource 2026-06-23 12:08:51 -05:00
rseq.c rseq: Reenable performance optimizations conditionally 2026-05-06 17:40:27 +02:00
scftorture.c scftorture: Remove preempt_disable() in scftorture_invoke_one() 2026-07-16 09:24:56 +02:00
scs.c scs: fix a wrong parameter in __scs_magic 2025-11-12 10:00:13 -08:00
seccomp.c seccomp, treewide: Rename and convert __secure_computing() to return boolean 2026-07-12 12:38:02 +02:00
signal.c posix-cpu-timers: Prevent UAF caused by non-leader exec() race 2026-07-05 11:44:06 +02:00
smp.c SMP core updates: 2026-08-18 15:29:53 -07:00
smpboot.c sched/smp: Use the SMP version of idle_thread_set_boot_cpu() 2025-06-13 08:47:20 +02:00
smpboot.h
softirq.c preempt: Introduce HAS_SEPARATE_PREEMPT_RESCHED_BITS 2026-08-10 10:50:19 +02:00
stacktrace.c
static_call_inline.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
static_call.c
stop_machine.c stop_machine: Make stop_one_cpu_nowait() return void 2026-07-31 12:35:26 +02:00
sys_ni.c time: Respect COMPAT_32BIT_TIME for old time type functions 2026-07-07 23:52:53 +02:00
sys.c exec_state: relocate dumpable information 2026-05-26 11:02:01 +02:00
sysctl-test.c sysctl: move u8 register test to lib/test_sysctl.c 2025-04-14 14:13:41 +02:00
sysctl.c sysctl: fix uninitialized variable in proc_do_large_bitmap 2026-03-26 09:32:19 +01:00
task_work.c task_work: Fix NMI race condition 2025-10-29 10:29:54 +01:00
taskstats.c taskstats: retain dead thread stats in TGID queries 2026-05-28 21:24:41 -07:00
torture.c torture: Add torture_sched_set_normal() for user-specified nice values 2026-05-24 09:38:47 +02:00
tracepoint.c tracepoint: balance regfunc() on func_add() failure in tracepoint_add_func() 2026-04-14 05:17:02 -04:00
tsacct.c tsacct: skip all kernel threads 2026-01-26 19:07:13 -08:00
ucount.c binfmt_misc: correctly account pre-opened interpreters 2026-08-03 23:36:18 +02:00
uid16.c
uid16.h
umh.c fs: add umh argument to struct kernel_clone_args 2026-06-29 10:54:41 +02:00
up.c smp: Refactor remote CPU selection in smp_call_function_any() 2026-07-16 09:24:55 +02:00
user_namespace.c Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
user-return-notifier.c
user.c binfmt_misc: use RCU for the handler lookup 2026-08-03 10:08:36 +02:00
utsname_sysctl.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
utsname.c namespace-6.18-rc1 2025-09-29 11:20:29 -07:00
vhost_task.c vhost_task_create: kill unnecessary .exit_signal initialization 2026-06-10 02:17:00 -04:00
vmcore_info.c mm.git review status for linus..mm-nonmm-stable 2026-04-16 20:11:56 -07:00
watch_queue.c Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
watchdog_buddy.c watchdog/hardlockup: improve buddy system detection timeliness 2026-03-27 21:19:47 -07:00
watchdog_perf.c watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency 2026-02-08 00:13:35 -08:00
watchdog.c watchdog/hardlockup: improve buddy system detection timeliness 2026-03-27 21:19:47 -07:00
workqueue_internal.h workqueue: Show in-flight work item duration in stall diagnostics 2026-03-05 07:27:48 -10:00
workqueue.c workqueue: Changes for v7.2 2026-06-17 11:57:44 +01:00