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Linus Torvalds 4f9e7fabf8 Tracing fixes for 6.5:
- Fix ring buffer being permanently disabled due to missed record_disabled()
   Changing the trace cpu mask will disable the ring buffers for the CPUs no
   longer in the mask. But it fails to update the snapshot buffer. If a snapshot
   takes place, the accounting for the ring buffer being disabled is corrupted
   and this can lead to the ring buffer being permanently disabled.
 
 - Add test case for snapshot and cpu mask working together
 
 - Fix memleak by the function graph tracer not getting closed properly.
   The iterator is used to read the ring buffer. When it opens, it calls
   the open function of a tracer, and when it is closed, it calls the close
   iteration. While a trace is being read, it is still possible to change
   the tracer. If this happens between the function graph tracer and the
   wakeup tracer (which uses function graph tracing), the tracers are not
   closed properly during when the iterator sees the switch, and the wakeup
   function did not initialize its private pointer to NULL, which is used
   to know if the function graph tracer was the last tracer. It could be
   fooled in thinking it is, but then on exit it does not call the close
   function of the function graph tracer to clean up its data.
 
 - Fix synthetic events on big endian machines, by introducing a union
   that does the conversions properly.
 
 - Fix synthetic events from printing out the number of elements in the
   stacktrace when it shouldn't.
 
 - Fix synthetic events stacktrace to not print a bogus value at the end.
 
 - Introduce a pipe_cpumask that prevents the trace_pipe files from being
   opened by more than one task (file descriptor). There was a race found
   where if splice is called, the iter->ent could become stale and events
   could be missed. There's no point reading a producer/consumer file by
   more than one task as they will corrupt each other anyway. Add a cpumask
   that keeps track of the per_cpu trace_pipe files as well as the global
   trace_pipe file that prevents more than one open of a trace_pipe file
   that represents the same ring buffer. This prevents the race from
   happening.
 
 - Fix ftrace samples for arm64 to work with older compilers.
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Merge tag 'trace-v6.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix ring buffer being permanently disabled due to missed
   record_disabled()

   Changing the trace cpu mask will disable the ring buffers for the
   CPUs no longer in the mask. But it fails to update the snapshot
   buffer. If a snapshot takes place, the accounting for the ring buffer
   being disabled is corrupted and this can lead to the ring buffer
   being permanently disabled.

 - Add test case for snapshot and cpu mask working together

 - Fix memleak by the function graph tracer not getting closed properly.

   The iterator is used to read the ring buffer. When it opens, it calls
   the open function of a tracer, and when it is closed, it calls the
   close iteration. While a trace is being read, it is still possible to
   change the tracer.

   If this happens between the function graph tracer and the wakeup
   tracer (which uses function graph tracing), the tracers are not
   closed properly during when the iterator sees the switch, and the
   wakeup function did not initialize its private pointer to NULL, which
   is used to know if the function graph tracer was the last tracer. It
   could be fooled in thinking it is, but then on exit it does not call
   the close function of the function graph tracer to clean up its data.

 - Fix synthetic events on big endian machines, by introducing a union
   that does the conversions properly.

 - Fix synthetic events from printing out the number of elements in the
   stacktrace when it shouldn't.

 - Fix synthetic events stacktrace to not print a bogus value at the
   end.

 - Introduce a pipe_cpumask that prevents the trace_pipe files from
   being opened by more than one task (file descriptor).

   There was a race found where if splice is called, the iter->ent could
   become stale and events could be missed. There's no point reading a
   producer/consumer file by more than one task as they will corrupt
   each other anyway. Add a cpumask that keeps track of the per_cpu
   trace_pipe files as well as the global trace_pipe file that prevents
   more than one open of a trace_pipe file that represents the same ring
   buffer. This prevents the race from happening.

 - Fix ftrace samples for arm64 to work with older compilers.

* tag 'trace-v6.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  samples: ftrace: Replace bti assembly with hint for older compiler
  tracing: Introduce pipe_cpumask to avoid race on trace_pipes
  tracing: Fix memleak due to race between current_tracer and trace
  tracing/synthetic: Allocate one additional element for size
  tracing/synthetic: Skip first entry for stack traces
  tracing/synthetic: Use union instead of casts
  selftests/ftrace: Add a basic testcase for snapshot
  tracing: Fix cpu buffers unavailable due to 'record_disabled' missed
2023-08-24 19:39:20 -07:00
arch - Use LEA ...%rsp instead of ADD %rsp in the Zen1/2 SRSO return sequence 2023-08-19 10:46:02 +02:00
block block-6.5-2023-08-19 2023-08-19 17:31:46 +02:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto crypto: fix uninit-value in af_alg_free_resources 2023-08-18 18:30:09 +08:00
Documentation Networking fixes for 6.5-rc8, including fixes from wifi, can 2023-08-24 08:23:13 -07:00
drivers media fixes for v6.5-rc8 2023-08-24 19:10:53 -07:00
fs nfsd-6.5 fixes: 2023-08-24 14:30:47 -07:00
include Tracing fixes for 6.5: 2023-08-24 19:39:20 -07:00
init Kbuild updates for v6.5 2023-07-01 09:24:31 -07:00
io_uring io_uring/parisc: Adjust pgoff in io_uring mmap() for parisc 2023-08-08 12:37:01 -06:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel tracing: Introduce pipe_cpumask to avoid race on trace_pipes 2023-08-21 11:17:14 -04:00
lib 14 hotfixes. 11 of these are cc:stable and the remainder address post-6.4 2023-08-11 14:19:20 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: avoid 'might_sleep()' in get_mmap_lock_carefully() 2023-08-21 06:11:33 +02:00
net Networking fixes for 6.5-rc8, including fixes from wifi, can 2023-08-24 08:23:13 -07:00
rust rust: macros: vtable: fix HAS_* redefinition (gen_const_name) 2023-08-09 21:15:07 +02:00
samples samples: ftrace: Replace bti assembly with hint for older compiler 2023-08-21 22:03:58 -04:00
scripts Kbuild fixes for v6.5 (2nd) 2023-08-13 08:56:24 -07:00
security selinux/stable-6.5 PR 20230821 2023-08-22 10:38:29 -07:00
sound ALSA: hda/realtek - Remodified 3k pull low procedure 2023-08-16 14:20:27 +02:00
tools Tracing fixes for 6.5: 2023-08-24 19:39:20 -07:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt KVM: Grab a reference to KVM for VM and vCPU stats file descriptors 2023-07-29 11:05:28 -04:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Revert ".gitignore: ignore *.cover and *.mbx" 2023-07-04 15:05:12 -07:00
.mailmap mailmap: add entries for Simon Horman 2023-08-16 09:53:10 +01:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS - Address -Wmissing-prototype warnings 2023-06-26 16:43:54 -07:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Networking fixes for 6.5-rc8, including fixes from wifi, can 2023-08-24 08:23:13 -07:00
Makefile Linux 6.5-rc7 2023-08-20 15:02:52 +02:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.