<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/Documentation/trace, branch master</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'perf-tools-for-v7.3-2026-08-21' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools</title>
<updated>2026-08-22T15:47:50+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-08-22T15:47:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=473f6c8f437b049f8ec015d57cd59bb983b1d85c'/>
<id>473f6c8f437b049f8ec015d57cd59bb983b1d85c</id>
<content type='text'>
Pull perf tools updates from Namhyung Kim:
 "perf c2c:

   - Add 'function view' in perf c2c report TUI (switched by pressing
     'TAB' in the cacheline view) to organize samples around functions
     rather than cachelines in 3-level hierarchy:

	Level 1: Read-side function (sorted by estimated Cycles %)
	Level 2:   Contending writer functions (sorted by Store count)
	Level 3:     Shared cacheline addresses

     Users can navigate the entries and fold/unfold using 'e' key. An
     example output would look like below:

	Shared Data Functions Table     (19 entries, sorted on Cycles %)
	   Cycles    Store
	        %    count  Function / Contending function / Cacheline
	----------------------------------------------------------------------
	+  35.67%      876  + [k] cpupri_set
	+  24.31%      424  + [k] pull_rt_task
	-  16.53%      555  - [k] dequeue_pushable_task
	               145    - [k] pull_rt_task
	               145        0xff2d0082809da080
	               139    - [k] enqueue_pushable_task
	                70        0xff2d00a2071f9640
	                69        0xff2d0082809da000

  python module support:

   - Extend "perf" python module so that it can be fully functional. The
     goal is to run scripts directly, not by 'perf script' command. This
     would give better performance as well as more control to build
     standalone programs with UI.

   - Add LiveSession helper (perf_live.py) to enable live event
     collection directly from Python using perf.evlist and
     perf.parse_events.

  perf stat:

   - Add --hide-zero-events option to suppress zero-count events
   - Reject conflicting --field-separator and --json-output options
   - Fix duplicate event output with --for-each-cgroup

  perf sched latency:

   - Add -H/--histogram and --hist-mode (log|linear) options to show
     scheduler wait latency histograms
   - Add --time option to filter analysis by time span in 'perf sched
     latency'

  ARM CoreSight:

   - Synthesize callchains for instruction samples from CoreSight trace
     using thread stack ('--itrace=g...')
   - Support call indentation ('perf script -F +callindent') to display
     call depth hierarchy on branch samples
   - Decode ETE (Embedded Trace Extension) exception packets

  Build system:

   - Add 'make install-build-deps' target to install required packages
   - Parallelize JSON and metric pre-computation in jevents.py for
     faster builds

  Vendor event/metric updates:

   - Add Intel Nova Lake events and update tables for existing models
   - Update AMD Zen 5 and Zen 6 core events
   - Update Arm64 Tegra410 metrics and PowerPC hcalls

  Internal changes and fixes:

   - Harden trace-event and synthetic event parsing against corrupted
     data
   - Fix unwinding of multi-threaded processes in libdw unwinder
   - Fix memory leaks in various commands and python bindings
   - Speed up 'perf test' shell tests"

* tag 'perf-tools-for-v7.3-2026-08-21' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (232 commits)
  perf vendor events arm64: Fix Tegra410 Olympus event 0x0197
  perf vendor events arm64: fix swapped MetricGroup for Tegra410 L1 prefetcher metrics
  perf evlist: Warn when 'sleep' workload is used without system-wide (-a) option
  perf c2c: document function view in perf-c2c man page
  perf c2c: add function view browser UI and cacheline detail
  perf c2c: build and finalize the function view hierarchy
  perf c2c: add function view hierarchy entry creation
  perf c2c: add function view stats merge and memory management
  perf c2c: add HPP list parsing for function view columns
  perf c2c: add column rendering for function view
  perf c2c: add function view model skeleton
  perf c2c: extract shared data structures into util/c2c.h
  perf test sample-parsing: Validate PERF_FORMAT_GROUP values without LOST
  perf dso: Replace assert with runtime check in dso__read_symbol()
  perf dso: Guard against cache underflow on short reads in dso_cache__memcpy()
  perf dso: Use stored fd error instead of stale errno in file_read() and file_size()
  perf dso: Guard close() against invalid fd in dso__decompress_kmodule_path()
  perf dso: Guard against errno==0 when dso__get_filename() returns NULL
  perf build: install-build-deps: add RHEL family devel package mapping
  perf build: Remove leftover feature tests for removed cxx and clang support
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull perf tools updates from Namhyung Kim:
 "perf c2c:

   - Add 'function view' in perf c2c report TUI (switched by pressing
     'TAB' in the cacheline view) to organize samples around functions
     rather than cachelines in 3-level hierarchy:

	Level 1: Read-side function (sorted by estimated Cycles %)
	Level 2:   Contending writer functions (sorted by Store count)
	Level 3:     Shared cacheline addresses

     Users can navigate the entries and fold/unfold using 'e' key. An
     example output would look like below:

	Shared Data Functions Table     (19 entries, sorted on Cycles %)
	   Cycles    Store
	        %    count  Function / Contending function / Cacheline
	----------------------------------------------------------------------
	+  35.67%      876  + [k] cpupri_set
	+  24.31%      424  + [k] pull_rt_task
	-  16.53%      555  - [k] dequeue_pushable_task
	               145    - [k] pull_rt_task
	               145        0xff2d0082809da080
	               139    - [k] enqueue_pushable_task
	                70        0xff2d00a2071f9640
	                69        0xff2d0082809da000

  python module support:

   - Extend "perf" python module so that it can be fully functional. The
     goal is to run scripts directly, not by 'perf script' command. This
     would give better performance as well as more control to build
     standalone programs with UI.

   - Add LiveSession helper (perf_live.py) to enable live event
     collection directly from Python using perf.evlist and
     perf.parse_events.

  perf stat:

   - Add --hide-zero-events option to suppress zero-count events
   - Reject conflicting --field-separator and --json-output options
   - Fix duplicate event output with --for-each-cgroup

  perf sched latency:

   - Add -H/--histogram and --hist-mode (log|linear) options to show
     scheduler wait latency histograms
   - Add --time option to filter analysis by time span in 'perf sched
     latency'

  ARM CoreSight:

   - Synthesize callchains for instruction samples from CoreSight trace
     using thread stack ('--itrace=g...')
   - Support call indentation ('perf script -F +callindent') to display
     call depth hierarchy on branch samples
   - Decode ETE (Embedded Trace Extension) exception packets

  Build system:

   - Add 'make install-build-deps' target to install required packages
   - Parallelize JSON and metric pre-computation in jevents.py for
     faster builds

  Vendor event/metric updates:

   - Add Intel Nova Lake events and update tables for existing models
   - Update AMD Zen 5 and Zen 6 core events
   - Update Arm64 Tegra410 metrics and PowerPC hcalls

  Internal changes and fixes:

   - Harden trace-event and synthetic event parsing against corrupted
     data
   - Fix unwinding of multi-threaded processes in libdw unwinder
   - Fix memory leaks in various commands and python bindings
   - Speed up 'perf test' shell tests"

* tag 'perf-tools-for-v7.3-2026-08-21' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (232 commits)
  perf vendor events arm64: Fix Tegra410 Olympus event 0x0197
  perf vendor events arm64: fix swapped MetricGroup for Tegra410 L1 prefetcher metrics
  perf evlist: Warn when 'sleep' workload is used without system-wide (-a) option
  perf c2c: document function view in perf-c2c man page
  perf c2c: add function view browser UI and cacheline detail
  perf c2c: build and finalize the function view hierarchy
  perf c2c: add function view hierarchy entry creation
  perf c2c: add function view stats merge and memory management
  perf c2c: add HPP list parsing for function view columns
  perf c2c: add column rendering for function view
  perf c2c: add function view model skeleton
  perf c2c: extract shared data structures into util/c2c.h
  perf test sample-parsing: Validate PERF_FORMAT_GROUP values without LOST
  perf dso: Replace assert with runtime check in dso__read_symbol()
  perf dso: Guard against cache underflow on short reads in dso_cache__memcpy()
  perf dso: Use stored fd error instead of stale errno in file_read() and file_size()
  perf dso: Guard close() against invalid fd in dso__decompress_kmodule_path()
  perf dso: Guard against errno==0 when dso__get_filename() returns NULL
  perf build: install-build-deps: add RHEL family devel package mapping
  perf build: Remove leftover feature tests for removed cxx and clang support
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'landlock-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux</title>
<updated>2026-08-21T19:28:35+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-08-21T19:28:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7199989f3f3194d653b024ce8e79cea6b15e38b9'/>
<id>7199989f3f3194d653b024ce8e79cea6b15e38b9</id>
<content type='text'>
Pull Landlock update from Mickaël Salaün:
 "This improves observability with Landlock tracepoints support, which
  required some refactoring for dedicated domain types and common
  helpers shared with audit code.

  A LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS flag is also added to improve
  process-wide domain enforcement consistency.

  Whiteout files are now correctly handled and tested, and a few other
  fixes"

* tag 'landlock-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux: (34 commits)
  landlock: Document tracepoints
  selftests/landlock: Add landlock_enforce_domain trace tests
  selftests/landlock: Add scope and ptrace tracepoint tests
  selftests/landlock: Add network tracepoint tests
  selftests/landlock: Add filesystem tracepoint tests
  selftests/landlock: Add trace event test infrastructure and tests
  landlock: Add tracepoints for ptrace and scope denials
  landlock: Add landlock_deny_access_fs and landlock_deny_access_net
  landlock: Add tracepoints for rule checking
  landlock: Add landlock_enforce_domain tracepoint
  landlock: Add create_domain and free_domain tracepoints
  landlock: Add landlock_add_rule_fs and landlock_add_rule_net tracepoints
  landlock: Add create_ruleset and free_ruleset tracepoints
  landlock: Consolidate access-right and scope names in a shared header
  landlock: Decouple the per-denial logging decision from CONFIG_AUDIT
  landlock: Split denial logging from audit into common framework
  landlock: Split struct landlock_domain from struct landlock_ruleset
  landlock: Move domain query functions to domain.c
  landlock: Prepare ruleset and domain type split
  samples/landlock: Add LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS to sampler
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull Landlock update from Mickaël Salaün:
 "This improves observability with Landlock tracepoints support, which
  required some refactoring for dedicated domain types and common
  helpers shared with audit code.

  A LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS flag is also added to improve
  process-wide domain enforcement consistency.

  Whiteout files are now correctly handled and tested, and a few other
  fixes"

* tag 'landlock-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux: (34 commits)
  landlock: Document tracepoints
  selftests/landlock: Add landlock_enforce_domain trace tests
  selftests/landlock: Add scope and ptrace tracepoint tests
  selftests/landlock: Add network tracepoint tests
  selftests/landlock: Add filesystem tracepoint tests
  selftests/landlock: Add trace event test infrastructure and tests
  landlock: Add tracepoints for ptrace and scope denials
  landlock: Add landlock_deny_access_fs and landlock_deny_access_net
  landlock: Add tracepoints for rule checking
  landlock: Add landlock_enforce_domain tracepoint
  landlock: Add create_domain and free_domain tracepoints
  landlock: Add landlock_add_rule_fs and landlock_add_rule_net tracepoints
  landlock: Add create_ruleset and free_ruleset tracepoints
  landlock: Consolidate access-right and scope names in a shared header
  landlock: Decouple the per-denial logging decision from CONFIG_AUDIT
  landlock: Split denial logging from audit into common framework
  landlock: Split struct landlock_domain from struct landlock_ruleset
  landlock: Move domain query functions to domain.c
  landlock: Prepare ruleset and domain type split
  samples/landlock: Add LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS to sampler
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'probes-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace</title>
<updated>2026-08-20T22:11:52+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-08-20T22:11:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6439079365dcb33c6701f5f0e480ac2c17312b6b'/>
<id>6439079365dcb33c6701f5f0e480ac2c17312b6b</id>
<content type='text'>
Pull probes updates from Masami Hiramatsu:
 "BTF typecasting and variable fetch enhancements:

   - Typecast support across probe events: Extended BTF typecasting
     syntax (e.g., (STRUCT)PARAM-&gt;MEMBER) to kprobes, uprobes, and
     fprobes on function entry and return

   - Nested typecasts: Added support for chaining and nesting typecasts
     up to 3 levels, including casting registers and stack variables

   - Field specifier option: Added (STRUCT,FIELD) syntax to emulate
     container_of(), allowing retrieval of parent structures from member
     pointers

   - $current variable support: Introduced $current special variable to
     access the running task_struct via BTF dereferencing

   - Per-CPU variable access: Added this_cpu_read() and this_cpu_ptr()
     fetcharg methods to trace CPU-local data safely

   - Fetcharg bytecode dumper: Added CONFIG_PROBE_EVENTS_DUMP_FETCHARG
     to dump the compiled fetcharg bytecode instructions as comments in
     dynamic_events

   - Extended symbol name handling: Removed the MAX_COMMON_HEAD_LEN
     limit and extended MAX_ARGSTR_LEN to 256 bytes, enabling probing of
     long symbols, mangled Rust symbols and complex BTF expressions

   - eprobe variable syntax: Allowed eprobes to reference event fields
     directly without requiring a '$' prefix

   - Cleanup unused parameters, redundant codes, duplicate macros and
     pointer arithmetic

   - Use a ternary operator for simplifying fetch_type_from_btf_type()

  Expanded boot time dynamic probe support:

   - Add boot-time tracing configuration support for event probes
     (eprobes), function probes (fprobes), and tracepoint probes
     (tprobes)

   - Allow comment lines ('#') in dynamic_events file

  Optimization, robustness, and cleanups:

   - Simplify fprobe_remove_ips() by reusing graph and ftrace helpers

   - Remove __packed attribute from struct __fprobe_header to avoid
     unaligned memory access penalties on RISC architectures

   - Remove redundant memset() calls in perf event probe handlers

   - Replace legacy __ASSEMBLY__ with __ASSEMBLER__ in header files

  Selftests &amp; refactoring:

   - Refactor parse_probe_arg() and parse_probe_vars(), and eliminate
     recursion in probe argument parsing to protect kernel stack depth

   - Add selftests for BTF typecasts and module probing without module
     prefixes

   - Force LC_ALL=C in ftracetest to prevent test failures on localized
     systems

   - Refactor btf_type_skip_modifiers() to remove ignored id parameter

   - Sort ERRORS list in trace_probe.h alphabetically

   - Fix typo in fprobe docs, and trace_fprobe function name

   - Rename FETCH_OP_DATA to FETCH_OP_IMMSTR

   - Make file offset error message probe-agnostic"

* tag 'probes-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (37 commits)
  fprobe: Simplify fprobe_remove_ips() by reusing existing helpers
  tracing/boot: Add support for eprobe, fprobe, and tprobe events
  selftests/ftrace: Force C locale in ftracetest
  tracing/probes: Treating longer symbol name on event comparation
  docs: trace: fprobe: fix 'thos' spelling
  tracing/probes: Fix extra whitespace in trace_probe_kernel.h
  tracing/kprobe: Remove redundant memset in kprobe_perf_func()
  tracing/fprobe: Remove redundant memset in fentry_perf_func()
  tracing/fprobe: Remove redundant snprintf in trace_fprobe_match_command_head()
  tracing/probes: Simplify BTF_KIND_PTR case in fetch_type_from_btf_type()
  tracing/probes: Cleanup pointer arithmetic in store_trace_entry_data()
  tracing/probes: Remove unused parameter from parse_probe_var_retval()
  tracing/probes: Remove redundant bounds check in trace_probe_compare_arg_type()
  tracing/probes: Remove redundant boolean conversion in trace_probe_has_single_file()
  tracing/probes: Remove duplicate MAX_ARRAY_LEN macro definition
  selftests/ftrace: Add test case for a symbol in a module without module name
  tracing/probes: Eliminate recursion in parse_probe_arg()
  tracing/probes: Extend max length of argument string
  tracing/probes: Sort ERRORS list in trace_probe.h alphabetically
  tracing/probes: Refactor parse_probe_arg()
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull probes updates from Masami Hiramatsu:
 "BTF typecasting and variable fetch enhancements:

   - Typecast support across probe events: Extended BTF typecasting
     syntax (e.g., (STRUCT)PARAM-&gt;MEMBER) to kprobes, uprobes, and
     fprobes on function entry and return

   - Nested typecasts: Added support for chaining and nesting typecasts
     up to 3 levels, including casting registers and stack variables

   - Field specifier option: Added (STRUCT,FIELD) syntax to emulate
     container_of(), allowing retrieval of parent structures from member
     pointers

   - $current variable support: Introduced $current special variable to
     access the running task_struct via BTF dereferencing

   - Per-CPU variable access: Added this_cpu_read() and this_cpu_ptr()
     fetcharg methods to trace CPU-local data safely

   - Fetcharg bytecode dumper: Added CONFIG_PROBE_EVENTS_DUMP_FETCHARG
     to dump the compiled fetcharg bytecode instructions as comments in
     dynamic_events

   - Extended symbol name handling: Removed the MAX_COMMON_HEAD_LEN
     limit and extended MAX_ARGSTR_LEN to 256 bytes, enabling probing of
     long symbols, mangled Rust symbols and complex BTF expressions

   - eprobe variable syntax: Allowed eprobes to reference event fields
     directly without requiring a '$' prefix

   - Cleanup unused parameters, redundant codes, duplicate macros and
     pointer arithmetic

   - Use a ternary operator for simplifying fetch_type_from_btf_type()

  Expanded boot time dynamic probe support:

   - Add boot-time tracing configuration support for event probes
     (eprobes), function probes (fprobes), and tracepoint probes
     (tprobes)

   - Allow comment lines ('#') in dynamic_events file

  Optimization, robustness, and cleanups:

   - Simplify fprobe_remove_ips() by reusing graph and ftrace helpers

   - Remove __packed attribute from struct __fprobe_header to avoid
     unaligned memory access penalties on RISC architectures

   - Remove redundant memset() calls in perf event probe handlers

   - Replace legacy __ASSEMBLY__ with __ASSEMBLER__ in header files

  Selftests &amp; refactoring:

   - Refactor parse_probe_arg() and parse_probe_vars(), and eliminate
     recursion in probe argument parsing to protect kernel stack depth

   - Add selftests for BTF typecasts and module probing without module
     prefixes

   - Force LC_ALL=C in ftracetest to prevent test failures on localized
     systems

   - Refactor btf_type_skip_modifiers() to remove ignored id parameter

   - Sort ERRORS list in trace_probe.h alphabetically

   - Fix typo in fprobe docs, and trace_fprobe function name

   - Rename FETCH_OP_DATA to FETCH_OP_IMMSTR

   - Make file offset error message probe-agnostic"

* tag 'probes-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (37 commits)
  fprobe: Simplify fprobe_remove_ips() by reusing existing helpers
  tracing/boot: Add support for eprobe, fprobe, and tprobe events
  selftests/ftrace: Force C locale in ftracetest
  tracing/probes: Treating longer symbol name on event comparation
  docs: trace: fprobe: fix 'thos' spelling
  tracing/probes: Fix extra whitespace in trace_probe_kernel.h
  tracing/kprobe: Remove redundant memset in kprobe_perf_func()
  tracing/fprobe: Remove redundant memset in fentry_perf_func()
  tracing/fprobe: Remove redundant snprintf in trace_fprobe_match_command_head()
  tracing/probes: Simplify BTF_KIND_PTR case in fetch_type_from_btf_type()
  tracing/probes: Cleanup pointer arithmetic in store_trace_entry_data()
  tracing/probes: Remove unused parameter from parse_probe_var_retval()
  tracing/probes: Remove redundant bounds check in trace_probe_compare_arg_type()
  tracing/probes: Remove redundant boolean conversion in trace_probe_has_single_file()
  tracing/probes: Remove duplicate MAX_ARRAY_LEN macro definition
  selftests/ftrace: Add test case for a symbol in a module without module name
  tracing/probes: Eliminate recursion in parse_probe_arg()
  tracing/probes: Extend max length of argument string
  tracing/probes: Sort ERRORS list in trace_probe.h alphabetically
  tracing/probes: Refactor parse_probe_arg()
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'ftrace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace</title>
<updated>2026-08-19T21:01:58+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-08-19T21:01:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=00d66b29a66ce18e417a8436076c629d03186a27'/>
<id>00d66b29a66ce18e417a8436076c629d03186a27</id>
<content type='text'>
Pull ftrace updates from Steven Rostedt:

 - Deprecrate ftrace_enabled in disabling ftrace

   The file /proc/sys/kernel/ftrace_enabled was created when ftrace was
   first introduced back in 2008. It was to be a "kill switch" if
   something was to go wrong. It was also used as a way to turn off
   function tracing for the latency tracers that would have it on by
   default. But in 2013 (Linux 3.10) the option "function-trace" was
   introduced to disable function tracing for the latency tracers as the
   "ftrace_enabled" file was considered too big of a hammer and caused
   too many side effects.

   When live kernel patching came along, disabling ftrace via the
   ftrace_enabled file would put the system into an unstable state if a
   live kernel patch was installed. This created the need to mark some
   function hooks as "PERMANENT".

   Now there's a need for BPF usage marked as PERMANENT for the same
   reasons.

   The file "ftrace_enabled" usage is no longer viable. It doesn't do
   what it says it does and there is no reason to use it.

   Make writing '0' to it a nop and print a message saying its usage is
   deprecated. The return value of writing '0' is -EOPNOTSUPP so that
   user space will error on that write (hopefully to inform any
   developer that it no longer works).

   Eventually the file should be removed completely, but for now just
   making it not do anything is the path forward to that.

 - Update the livepatch tests to handle ftrace_enabled being disabled

   Because in the past, livepatch was broken by ftrace_enabled being
   turned off, there's a test case that checks to make sure it still
   doesn't break. But having the write of '0' return an error caused
   that test to break. Updated the test to handle the new change.

* tag 'ftrace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  selftests/livepatch: update test-ftrace.sh for deprecated ftrace_enabled
  ftrace: deprecate disabling via ftrace_enabled sysctl
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ftrace updates from Steven Rostedt:

 - Deprecrate ftrace_enabled in disabling ftrace

   The file /proc/sys/kernel/ftrace_enabled was created when ftrace was
   first introduced back in 2008. It was to be a "kill switch" if
   something was to go wrong. It was also used as a way to turn off
   function tracing for the latency tracers that would have it on by
   default. But in 2013 (Linux 3.10) the option "function-trace" was
   introduced to disable function tracing for the latency tracers as the
   "ftrace_enabled" file was considered too big of a hammer and caused
   too many side effects.

   When live kernel patching came along, disabling ftrace via the
   ftrace_enabled file would put the system into an unstable state if a
   live kernel patch was installed. This created the need to mark some
   function hooks as "PERMANENT".

   Now there's a need for BPF usage marked as PERMANENT for the same
   reasons.

   The file "ftrace_enabled" usage is no longer viable. It doesn't do
   what it says it does and there is no reason to use it.

   Make writing '0' to it a nop and print a message saying its usage is
   deprecated. The return value of writing '0' is -EOPNOTSUPP so that
   user space will error on that write (hopefully to inform any
   developer that it no longer works).

   Eventually the file should be removed completely, but for now just
   making it not do anything is the path forward to that.

 - Update the livepatch tests to handle ftrace_enabled being disabled

   Because in the past, livepatch was broken by ftrace_enabled being
   turned off, there's a test case that checks to make sure it still
   doesn't break. But having the write of '0' return an error caused
   that test to break. Updated the test to handle the new change.

* tag 'ftrace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  selftests/livepatch: update test-ftrace.sh for deprecated ftrace_enabled
  ftrace: deprecate disabling via ftrace_enabled sysctl
</pre>
</div>
</content>
</entry>
<entry>
<title>landlock: Document tracepoints</title>
<updated>2026-08-17T08:17:19+00:00</updated>
<author>
<name>Mickaël Salaün</name>
<email>mic@digikod.net</email>
</author>
<published>2026-08-11T09:43:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=172b6a6d8463562b0cbebfd66f770b078f81966b'/>
<id>172b6a6d8463562b0cbebfd66f770b078f81966b</id>
<content type='text'>
Until now, Landlock observability documentation covered only audit
records.  The tracepoints added by the previous commits introduce a
second channel with different semantics (firing regardless of audit
configuration and domain log flags, exposing the full ruleset and domain
state to eBPF via BTF), which kernel developers, administrators, and
userspace tool authors need to discover and compare against audit.

Add a dedicated "Landlock Trace Events" reference covering the event
categories, enabling events via tracefs, ruleset versioning, eBPF access
through BPF_RAW_TRACEPOINT, and the same_exec and logged denial fields
(logged being the kernel's audit-logging decision, so a stateless ftrace
filter can select the denials audit would record with logged==1).
Cross-reference it from the administrator, kernel-internals, and
userspace API documents, contrasting tracepoints with audit: when each
channel is preferred, what each guarantees, and how NOAUDIT hooks and
audit rate limiting affect them.

Also document the relational other-party domain fields the scope and
ptrace denial tracepoints expose (tracee_domain, target_domain,
peer_domain; 0 when the other party is unsandboxed), so a consumer can
resolve them against the lifecycle events and reproduce the two-domain
verdict.

Cc: Günther Noack &lt;gnoack@google.com&gt;
Cc: Tingmao Wang &lt;m@maowtm.org&gt;
Link: https://patch.msgid.link/20260811094338.288094-20-mic@digikod.net
[mic: Update dates]
Signed-off-by: Mickaël Salaün &lt;mic@digikod.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Until now, Landlock observability documentation covered only audit
records.  The tracepoints added by the previous commits introduce a
second channel with different semantics (firing regardless of audit
configuration and domain log flags, exposing the full ruleset and domain
state to eBPF via BTF), which kernel developers, administrators, and
userspace tool authors need to discover and compare against audit.

Add a dedicated "Landlock Trace Events" reference covering the event
categories, enabling events via tracefs, ruleset versioning, eBPF access
through BPF_RAW_TRACEPOINT, and the same_exec and logged denial fields
(logged being the kernel's audit-logging decision, so a stateless ftrace
filter can select the denials audit would record with logged==1).
Cross-reference it from the administrator, kernel-internals, and
userspace API documents, contrasting tracepoints with audit: when each
channel is preferred, what each guarantees, and how NOAUDIT hooks and
audit rate limiting affect them.

Also document the relational other-party domain fields the scope and
ptrace denial tracepoints expose (tracee_domain, target_domain,
peer_domain; 0 when the other party is unsandboxed), so a consumer can
resolve them against the lifecycle events and reproduce the two-domain
verdict.

Cc: Günther Noack &lt;gnoack@google.com&gt;
Cc: Tingmao Wang &lt;m@maowtm.org&gt;
Link: https://patch.msgid.link/20260811094338.288094-20-mic@digikod.net
[mic: Update dates]
Signed-off-by: Mickaël Salaün &lt;mic@digikod.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ftrace: deprecate disabling via ftrace_enabled sysctl</title>
<updated>2026-08-11T01:21:18+00:00</updated>
<author>
<name>Andrey Grodzovsky</name>
<email>andrey.grodzovsky@crowdstrike.com</email>
</author>
<published>2026-08-06T15:29:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b0c857049153680e1b6ccb59abf359a4ca523561'/>
<id>b0c857049153680e1b6ccb59abf359a4ca523561</id>
<content type='text'>
Writing 0 to kernel.ftrace_enabled has not reliably disabled ftrace
for years (FTRACE_OPS_FL_PERMANENT users already block it, and more
callers rely on ftrace always being on). Refuse the write instead of
leaving it in an inconsistent "disables some, not all" state: return
-EOPNOTSUPP and log a message. Reads and enabling (writing 1) are
unaffected.

Update the docs to note the deprecation up front.

Link: https://patch.msgid.link/20260806153000.4184871-2-andrey.grodzovsky@crowdstrike.com
Suggested-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Signed-off-by: Andrey Grodzovsky &lt;andrey.grodzovsky@crowdstrike.com&gt;
Acked-by: Song Liu &lt;song@kernel.org&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Writing 0 to kernel.ftrace_enabled has not reliably disabled ftrace
for years (FTRACE_OPS_FL_PERMANENT users already block it, and more
callers rely on ftrace always being on). Refuse the write instead of
leaving it in an inconsistent "disables some, not all" state: return
-EOPNOTSUPP and log a message. Reads and enabling (writing 1) are
unaffected.

Update the docs to note the deprecation up front.

Link: https://patch.msgid.link/20260806153000.4184871-2-andrey.grodzovsky@crowdstrike.com
Suggested-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Signed-off-by: Andrey Grodzovsky &lt;andrey.grodzovsky@crowdstrike.com&gt;
Acked-by: Song Liu &lt;song@kernel.org&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tracing/boot: Add support for eprobe, fprobe, and tprobe events</title>
<updated>2026-08-08T12:20:55+00:00</updated>
<author>
<name>Masami Hiramatsu (Google)</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2026-08-07T21:44:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d093d4524bb12eda49c3654cb04ad4663c2471f8'/>
<id>d093d4524bb12eda49c3654cb04ad4663c2471f8</id>
<content type='text'>
Boot-time tracing currently supports kprobe-events and synthetic-events
under per-event configuration options.

Extend boot-time tracing to support newly added dynamic probe types:
- event probes (eprobe) under the "eprobes" event group
- function probes (fprobe) under the "fprobes" event group
- tracepoint probes (tprobe) under the "tracepoints" or "tprobes"
  event group

To support this cleanly, update dyn_event_create() in trace_dynevent.c
so that passing NULL as the type parameter delegates to
create_dyn_event(), allowing generic creation of any registered
dynamic event type from a raw command string.

Update Documentation/trace/boottime-trace.rst accordingly to describe
the new per-event bootconfig options.

Link: https://lore.kernel.org/all/178613905149.259829.18185480460810689421.stgit@devnote2/

Assisted-by: Antigravity:gemini-3.6-flash
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;

Changes in v3:
 - Check return values of strscpy() and snprintf() in trace_boot_add_probe_event()
   to prevent silent buffer truncation when constructing probe event strings.

Changes in v2:
 - Fix raw command detection logic for eprobes, fprobes, and tprobes
   by requiring ':' or isspace() after type prefix.
 - Consolidate duplicate loop logic into trace_boot_add_probe_event()
   helper function.</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Boot-time tracing currently supports kprobe-events and synthetic-events
under per-event configuration options.

Extend boot-time tracing to support newly added dynamic probe types:
- event probes (eprobe) under the "eprobes" event group
- function probes (fprobe) under the "fprobes" event group
- tracepoint probes (tprobe) under the "tracepoints" or "tprobes"
  event group

To support this cleanly, update dyn_event_create() in trace_dynevent.c
so that passing NULL as the type parameter delegates to
create_dyn_event(), allowing generic creation of any registered
dynamic event type from a raw command string.

Update Documentation/trace/boottime-trace.rst accordingly to describe
the new per-event bootconfig options.

Link: https://lore.kernel.org/all/178613905149.259829.18185480460810689421.stgit@devnote2/

Assisted-by: Antigravity:gemini-3.6-flash
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;

Changes in v3:
 - Check return values of strscpy() and snprintf() in trace_boot_add_probe_event()
   to prevent silent buffer truncation when constructing probe event strings.

Changes in v2:
 - Fix raw command detection logic for eprobes, fprobes, and tprobes
   by requiring ':' or isspace() after type prefix.
 - Consolidate duplicate loop logic into trace_boot_add_probe_event()
   helper function.</pre>
</div>
</content>
</entry>
<entry>
<title>Documentation/rv: Explain epoll and aborted sleeps</title>
<updated>2026-08-04T14:11:28+00:00</updated>
<author>
<name>Chao Liu</name>
<email>chao.liu@processmission.com</email>
</author>
<published>2026-07-29T08:11:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7d81675d1bb2cc6db61a2d93b1e0dc7fb0929f9c'/>
<id>7d81675d1bb2cc6db61a2d93b1e0dc7fb0929f9c</id>
<content type='text'>
epoll_wait() is a valid sleeping reason for real-time tasks because it
uses PI-aware locking, but the rtapp sleep monitor documentation only
discusses clock_nanosleep() and futexes. Document it.

ABORT_SLEEP represents a task restoring TASK_RUNNING before entering
the scheduler. Since the task does not actually block, it becomes
runnable again without a wakeup sequence unsafe for real-time. Document
this behavior.

Signed-off-by: Chao Liu &lt;chao.liu@processmission.com&gt;
Reviewed-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Reviewed-by: Nam Cao &lt;namcao@linutronix.de&gt;
Link: https://lore.kernel.org/r/20260729081102.73138-1-chao.liu@processmission.com
Signed-off-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
epoll_wait() is a valid sleeping reason for real-time tasks because it
uses PI-aware locking, but the rtapp sleep monitor documentation only
discusses clock_nanosleep() and futexes. Document it.

ABORT_SLEEP represents a task restoring TASK_RUNNING before entering
the scheduler. Since the task does not actually block, it becomes
runnable again without a wakeup sequence unsafe for real-time. Document
this behavior.

Signed-off-by: Chao Liu &lt;chao.liu@processmission.com&gt;
Reviewed-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Reviewed-by: Nam Cao &lt;namcao@linutronix.de&gt;
Link: https://lore.kernel.org/r/20260729081102.73138-1-chao.liu@processmission.com
Signed-off-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf hisi-ptt: Fix PTT trace TLP header parsing</title>
<updated>2026-07-31T22:48:12+00:00</updated>
<author>
<name>Sizhe Liu</name>
<email>liusizhe5@huawei.com</email>
</author>
<published>2026-07-30T06:27:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2b8a2e5d424f0b3369054305d0bf6a5b9faee6c1'/>
<id>2b8a2e5d424f0b3369054305d0bf6a5b9faee6c1</id>
<content type='text'>
TLP Headers traced by HiSilicon PCIe tune and trace device (PTT) in
4DW format are shown in the document as below:
bits [31:30] [ 29:25 ][24][23][22][21][    20:11   ][    10:0    ]
     |-----|---------|---|---|---|---|-------------|-------------|
DW0  [ Fmt ][  Type  ][T9][T8][TH][SO][   Length   ][    Time    ]
DW1  [                     Header DW1                            ]
DW2  [                     Header DW2                            ]
DW3  [                     Header DW3                            ]

Problem:
The DW0 bit field layout of the hisi_ptt_4dw union does not match the
actual bit ordering in little-endian memory, causing incorrect field
decoding.

Test on Kunpeng 930 SOC, generating data flow with `iperf` commands:
- server side:
    iperf -s
- client side:
    iperf -c $ip_addr -t 30

Trace the TLP headers with hisi_ptt on server side at the same time:
  perf record -e hisi_ptt12_0/type=4,filter=0x05101,direction=2,format=0/ \
  --max-size 50M -o perf.data &amp;
The trace aims to capture completion TLPs, learn more in the document:
  https://docs.kernel.org/trace/hisi-ptt.html

Decode perf.data with hisi_ptt decoder:
  perf report -D

The hisi_ptt decoder produces the following result:
[...perf headers and other information]
. ... HISI PTT data: size 8388608 bytes
.  00000000: 68 87 20 94                                 Format 3 Type 1a T9 0 T8 1 TH 1 SO 1 Length 10 Time 4a1
.  00000004: 40 00 00 00                                 Header DW1
.  00000008: 40 00 01 51                                 Header DW2
.  0000000c: 00 00 00 00                                 Header DW3
[...other hisi_ptt TLP headers]

According to PCIe r5.0 sec 2.2.1, the Fmt &amp; Type of Cpl/CplD is supposed
to be 8b'00001010' / 8b'01001010'
However, the Format &amp; Type decoder analyzing result is 8b'01111010'.
It does not match field encodings of any TLP.

Correct decoder result should be:
[...perf headers and other information]
. ... HISI PTT data: size 8388608 bytes
.  00000000: 94 20 87 68                                 Format 2 Type a T9 0 T8 0 TH 0 SO 1 Length 10 Time 768
.  00000004: 00 00 00 40                                 Header DW1
.  00000008: 51 01 00 40                                 Header DW2
.  0000000c: 00 00 00 00                                 Header DW3
[...other hisi_ptt TLP headers]

To solve the problem:
1. Drop the union and C bitfield struct, store the raw DW value in
a plain uint32_t, and extract the fields with FIELD_GET() against
GENMASK/BIT masks declared in the header so they can be reused by
other translation units. The masks are portable across endianness and
compilers.

2. Print all DW hex values in big-endian byte order for readability,
matching the bit field layout shown in the 4DW format diagram.

3. Read the DW value with get_unaligned_le32() instead of an unaligned
pointer cast, avoiding both strict-aliasing violations and
alignment hazards on hosts that do not support unaligned access.

Cc: stable@vger.kernel.org
Fixes: 5e91e57e6809 ("perf auxtrace arm64: Add support for parsing HiSilicon PCIe Trace packet")
Reviewed-by: James Clark &lt;james.clark@linaro.org&gt;
Signed-off-by: Sizhe Liu &lt;liusizhe5@huawei.com&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
TLP Headers traced by HiSilicon PCIe tune and trace device (PTT) in
4DW format are shown in the document as below:
bits [31:30] [ 29:25 ][24][23][22][21][    20:11   ][    10:0    ]
     |-----|---------|---|---|---|---|-------------|-------------|
DW0  [ Fmt ][  Type  ][T9][T8][TH][SO][   Length   ][    Time    ]
DW1  [                     Header DW1                            ]
DW2  [                     Header DW2                            ]
DW3  [                     Header DW3                            ]

Problem:
The DW0 bit field layout of the hisi_ptt_4dw union does not match the
actual bit ordering in little-endian memory, causing incorrect field
decoding.

Test on Kunpeng 930 SOC, generating data flow with `iperf` commands:
- server side:
    iperf -s
- client side:
    iperf -c $ip_addr -t 30

Trace the TLP headers with hisi_ptt on server side at the same time:
  perf record -e hisi_ptt12_0/type=4,filter=0x05101,direction=2,format=0/ \
  --max-size 50M -o perf.data &amp;
The trace aims to capture completion TLPs, learn more in the document:
  https://docs.kernel.org/trace/hisi-ptt.html

Decode perf.data with hisi_ptt decoder:
  perf report -D

The hisi_ptt decoder produces the following result:
[...perf headers and other information]
. ... HISI PTT data: size 8388608 bytes
.  00000000: 68 87 20 94                                 Format 3 Type 1a T9 0 T8 1 TH 1 SO 1 Length 10 Time 4a1
.  00000004: 40 00 00 00                                 Header DW1
.  00000008: 40 00 01 51                                 Header DW2
.  0000000c: 00 00 00 00                                 Header DW3
[...other hisi_ptt TLP headers]

According to PCIe r5.0 sec 2.2.1, the Fmt &amp; Type of Cpl/CplD is supposed
to be 8b'00001010' / 8b'01001010'
However, the Format &amp; Type decoder analyzing result is 8b'01111010'.
It does not match field encodings of any TLP.

Correct decoder result should be:
[...perf headers and other information]
. ... HISI PTT data: size 8388608 bytes
.  00000000: 94 20 87 68                                 Format 2 Type a T9 0 T8 0 TH 0 SO 1 Length 10 Time 768
.  00000004: 00 00 00 40                                 Header DW1
.  00000008: 51 01 00 40                                 Header DW2
.  0000000c: 00 00 00 00                                 Header DW3
[...other hisi_ptt TLP headers]

To solve the problem:
1. Drop the union and C bitfield struct, store the raw DW value in
a plain uint32_t, and extract the fields with FIELD_GET() against
GENMASK/BIT masks declared in the header so they can be reused by
other translation units. The masks are portable across endianness and
compilers.

2. Print all DW hex values in big-endian byte order for readability,
matching the bit field layout shown in the 4DW format diagram.

3. Read the DW value with get_unaligned_le32() instead of an unaligned
pointer cast, avoiding both strict-aliasing violations and
alignment hazards on hosts that do not support unaligned access.

Cc: stable@vger.kernel.org
Fixes: 5e91e57e6809 ("perf auxtrace arm64: Add support for parsing HiSilicon PCIe Trace packet")
Reviewed-by: James Clark &lt;james.clark@linaro.org&gt;
Signed-off-by: Sizhe Liu &lt;liusizhe5@huawei.com&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>docs: trace: fprobe: fix 'thos' spelling</title>
<updated>2026-07-28T14:54:59+00:00</updated>
<author>
<name>shaikh.kamal</name>
<email>shaikhkamal2012@gmail.com</email>
</author>
<published>2026-07-26T06:56:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d0d7dc1a70da6d65bef565f647c41febf3d881dd'/>
<id>d0d7dc1a70da6d65bef565f647c41febf3d881dd</id>
<content type='text'>
Fix spelling error reported by codespell: thos -&gt; those.
No functional change.

Link: https://lore.kernel.org/all/20260726065633.20897-1-shaikhkamal2012@gmail.com/

Signed-off-by: shaikh.kamal &lt;shaikhkamal2012@gmail.com&gt;
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix spelling error reported by codespell: thos -&gt; those.
No functional change.

Link: https://lore.kernel.org/all/20260726065633.20897-1-shaikhkamal2012@gmail.com/

Signed-off-by: shaikh.kamal &lt;shaikhkamal2012@gmail.com&gt;
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
