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Linus Torvalds 99ddf2254f Tracing fixes for 6.3:
- Fix timerlat notification, as it was not triggering the
   notify to users when a new max latency was hit.
 
 - Do not trigger max latency if the tracing is off.
   When tracing is off, the ring buffer is not updated, it
   does not make sense to notify when there's a new max latency
   detected by the tracer, as why that latency happened is not available.
   The tracing logic still runs when the ring buffer is disabled, but
   it should not be triggering notifications.
 
 - Fix race on freeing the synthetic event "last_cmd" variable by
   adding a mutex around it.
 
 - Fix race between reader and writer of the ring buffer by adding
   memory barriers. When the writer is still on the reader page
   it must have its content visible on the buffer before it moves
   the commit index that the reader uses to know how much content is
   on the page.
 
 - Make get_lock_parent_ip() always inlined, as it uses _THIS_IP_
   and _RET_IP_, which gets broken if it is not inlined.
 
 - Make __field(int, arr[5]) in a TRACE_EVENT() macro fail to build.
   The field formats of trace events are calculated by using sizeof(type)
   and other means by what is passed into the structure macros like
   __field(). The __field() macro is only meant for atom types like
   int, long, short, pointer, etc. It is not meant for arrays. But
   the code will currently compile with arrays, but then the format
   produced will be inaccurate, and user space parsing tools will break.
   Two bugs have already been fixed, now add code that will make the
   kernel fail to build if another trace event includes this buggy
   field format.
 
 - Fix boot up snapshot code:
 
   Boot snapshots were triggering when not even asked for on the
   kernel command line. This was caused by two bugs.
 
   1) It would trigger a snapshot on any instance if one was created
      from the kernel command line.
 
   2) The error handling would only affect the top level instance.
      So the fact that a snapshot was done on a instance that didn't
      allocate a buffer triggered a warning written into the top level
      buffer, and worse yet, disabled the top level buffer.
 
 - Fix memory leak that was caused when an error was logged in a
   trace buffer instance, and then the buffer instance was removed.
   The allocated error log messages still need to be freed.
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Merge tag 'trace-v6.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix timerlat notification, as it was not triggering the notify to
   users when a new max latency was hit.

 - Do not trigger max latency if the tracing is off.

   When tracing is off, the ring buffer is not updated, it does not make
   sense to notify when there's a new max latency detected by the
   tracer, as why that latency happened is not available. The tracing
   logic still runs when the ring buffer is disabled, but it should not
   be triggering notifications.

 - Fix race on freeing the synthetic event "last_cmd" variable by adding
   a mutex around it.

 - Fix race between reader and writer of the ring buffer by adding
   memory barriers. When the writer is still on the reader page it must
   have its content visible on the buffer before it moves the commit
   index that the reader uses to know how much content is on the page.

 - Make get_lock_parent_ip() always inlined, as it uses _THIS_IP_ and
   _RET_IP_, which gets broken if it is not inlined.

 - Make __field(int, arr[5]) in a TRACE_EVENT() macro fail to build.

   The field formats of trace events are calculated by using
   sizeof(type) and other means by what is passed into the structure
   macros like __field(). The __field() macro is only meant for atom
   types like int, long, short, pointer, etc. It is not meant for
   arrays.

   The code will currently compile with arrays, but then the format
   produced will be inaccurate, and user space parsing tools will break.

   Two bugs have already been fixed, now add code that will make the
   kernel fail to build if another trace event includes this buggy field
   format.

 - Fix boot up snapshot code:

   Boot snapshots were triggering when not even asked for on the kernel
   command line. This was caused by two bugs:

    1) It would trigger a snapshot on any instance if one was created
       from the kernel command line.

    2) The error handling would only affect the top level instance.
       So the fact that a snapshot was done on a instance that didn't
       allocate a buffer triggered a warning written into the top level
       buffer, and worse yet, disabled the top level buffer.

 - Fix memory leak that was caused when an error was logged in a trace
   buffer instance, and then the buffer instance was removed.

   The allocated error log messages still needed to be freed.

* tag 'trace-v6.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Free error logs of tracing instances
  tracing: Fix ftrace_boot_snapshot command line logic
  tracing: Have tracing_snapshot_instance_cond() write errors to the appropriate instance
  tracing: Error if a trace event has an array for a __field()
  tracing/osnoise: Fix notify new tracing_max_latency
  tracing/timerlat: Notify new max thread latency
  ftrace: Mark get_lock_parent_ip() __always_inline
  ring-buffer: Fix race while reader and writer are on the same page
  tracing/synthetic: Fix races on freeing last_cmd
2023-04-05 09:11:08 -07:00
arch PPC: 2023-04-04 11:29:37 -07:00
block block: remove obsolete config BLOCK_COMPAT 2023-03-16 09:35:44 -06:00
certs Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
crypto asymmetric_keys: log on fatal failures in PE/pkcs7 2023-03-21 16:23:56 +00:00
Documentation PPC: 2023-04-04 11:29:37 -07:00
drivers hyperv-fixes for 6.3-rc6 2023-04-03 09:34:08 -07:00
fs nfsd-6.3 fixes: 2023-04-04 11:20:55 -07:00
include Tracing fixes for 6.3: 2023-04-05 09:11:08 -07:00
init bootconfig: Change message if no bootconfig with CONFIG_BOOT_CONFIG_FORCE=y 2023-03-22 22:21:43 +09:00
io_uring io_uring-6.3-2023-03-30 2023-03-31 12:30:13 -07:00
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: Free error logs of tracing instances 2023-04-05 09:54:37 -04:00
lib Fixes for 6.3-rc3: 2023-03-25 12:57:34 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 21 hotfixes, 8 of which are cc:stable. 11 are for MM, the remainder are 2023-03-24 18:06:11 -07:00
net nfsd-6.3 fixes: 2023-04-04 11:20:55 -07:00
rust Rust fixes for 6.3-rc1 2023-03-03 14:51:15 -08:00
samples LoongArch changes for v6.3 2023-03-01 09:27:00 -08:00
scripts Kbuild fixes for v6.3 (2nd) 2023-04-01 09:25:17 -07:00
security keys: Do not cache key in task struct if key is requested from kernel thread 2023-03-21 16:22:40 +00:00
sound ALSA: hda/realtek: Add quirk for Lenovo ZhaoYang CF4620Z 2023-03-29 14:45:07 +02:00
tools Including fixes from CAN and WPAN. 2023-03-30 14:05:21 -07:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM: PPC: Make KVM_CAP_IRQFD_RESAMPLE platform dependent 2023-03-31 11:19:05 -04:00
.clang-format cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore kbuild: rpm-pkg: move source components to rpmbuild/SOURCES 2023-03-16 22:45:56 +09:00
.mailmap mailmap: add entries for Richard Leitner 2023-03-23 17:18:35 -07:00
.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 There is no particular theme here - mainly quick hits all over the tree. 2023-02-23 17:55:40 -08:00
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 Driver core fixes for 6.3-rc5 2023-04-02 10:10:16 -07:00
Makefile Linux 6.3-rc5 2023-04-02 14:29:29 -07:00
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.