linux-stable.git/tools/tracing, branch v7.0.10

rtla: Fix segfault on multiple SIGINTs

2026-05-23T11:08:56+00:00

[ Upstream commit be8058f31b4e237604e4ce7599593ab68dc69ae7 ]

Detach stop_trace() from SIGINT/SIGALRM on tool clean-up to prevent it
from crashing RTLA by accessing freed memory.

This prevents a crash when multiple SIGINTs are received.

Fixes: d6899e560366 ("rtla/timerlat_hist: Abort event processing on second signal")
Fixes: 80967b354a76 ("rtla/timerlat_top: Abort event processing on second signal")
Reviewed-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260310160725.144443-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

tools/rtla: Generate optstring from long options

2026-05-23T11:08:56+00:00

[ Upstream commit 4a1cec7450b7159a0ee57403f44460ac4d618b4f ]

getopt_long() processes short and long options independently.
RTLA, like the majority of applications, uses both short and long
variants for each logical option.

Since the val member of struct option holds the letter of the short
variant, the string of short options can be reconstructed from the
array of long options.

Add getopt_auto() to generate optstring from an array of long options,
eliminating the need to maintain separate short option strings.

Signed-off-by: Costa Shulyupin 
Reviewed-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260108095011.2115719-1-costa.shul@redhat.com
Signed-off-by: Tomas Glozar 
Stable-dep-of: be8058f31b4e ("rtla: Fix segfault on multiple SIGINTs")
Signed-off-by: Sasha Levin

rtla/utils: Fix resource leak in set_comm_sched_attr()

2026-05-23T11:08:56+00:00

[ Upstream commit 5b6dc659ad792c72b3ff1be8039ae2945e030928 ]

The set_comm_sched_attr() function opens the /proc directory via
opendir() but fails to call closedir() on its successful exit path.
If the function iterates through all processes without error, it
returns 0 directly, leaking the DIR stream pointer.

Fix this by refactoring the function to use a single exit path. A
retval variable is introduced to track the success or failure status.
All exit points now jump to a unified out label that calls closedir()
before the function returns, ensuring the resource is always freed.

Fixes: dada03db9bb19 ("rtla: Remove procps-ng dependency")
Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260309195040.1019085-18-wander@redhat.com
Signed-off-by: Tomas Glozar 
Signed-off-by: Sasha Levin

rtla: Fix build without libbpf header

2026-03-30T16:44:48+00:00

rtla supports building without libbpf. However, BPF actions
patchset [1] adds an include of bpf/libbpf.h into timerlat_bpf.h,
which breaks build on systems that don't have libbpf headers
installed.

This is a leftover from a draft version of the patchset where
timerlat_bpf_set_action() (which takes a struct bpf_program * argument)
was defined in the header. timerlat_bpf.c already includes bpf/libbpf.h
via timerlat.skel.h when libbpf is present.

Remove the redundant include to fix build on systems without libbpf
headers.

[1] https://lore.kernel.org/linux-trace-kernel/20251126144205.331954-1-tglozar@redhat.com/T/

Cc: John Kacur 
Cc: Luis Goncalves 
Cc: Crystal Wood 
Cc: Costa Shulyupin 
Link: https://patch.msgid.link/20260330091207.16184-1-tglozar@redhat.com
Reported-by: Steven Rostedt (Google) 
Closes: https://lore.kernel.org/linux-trace-kernel/20260329122202.65a8b575@robin/
Fixes: 8cd0f08ac72e ("rtla/timerlat: Support tail call from BPF program")
Signed-off-by: Tomas Glozar 
Reviewed-by: Wander Lairson Costa 
Signed-off-by: Steven Rostedt (Google)

rtla: Fix parse_cpu_set() bug introduced by strtoi()

2026-01-13T07:32:52+00:00

The patch 'Replace atoi() with a robust strtoi()' introduced a bug
in parse_cpu_set(), which relies on partial parsing of the input string.

The function parses CPU specifications like '0-3,5' by incrementing
a pointer through the string. strtoi() rejects strings with trailing
characters, causing parse_cpu_set() to fail on any CPU list with
multiple entries.

Restore the original use of atoi() in parse_cpu_set().

Fixes: 7e9dfccf8f11 ("rtla: Replace atoi() with a robust strtoi()")
Signed-off-by: Costa Shulyupin 
Reviewed-by: Masami Hiramatsu (Google) 
Link: https://lore.kernel.org/r/20260112192642.212848-2-costa.shul@redhat.com
Signed-off-by: Tomas Glozar

rtla: Fix parse_cpu_set() return value documentation

2026-01-07T14:57:56+00:00

Correct the return value documentation for parse_cpu_set() function
in utils.c. The comment incorrectly stated that the function returns
1 on success and 0 on failure, but the actual implementation returns
0 on success and 1 on failure, following the common error-on-nonzero
convention used throughout the codebase.

This documentation fix ensures that developers reading the code
understand the correct return value semantics and prevents potential
misuse of the function's return value in conditional checks.

Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260106133655.249887-18-wander@redhat.com
Signed-off-by: Tomas Glozar

rtla: Ensure null termination after read operations in utils.c

2026-01-07T14:57:56+00:00

Add explicit null termination and buffer initialization for read()
operations in procfs_is_workload_pid() and get_self_cgroup() functions.
The read() system call does not null-terminate the data it reads, and
when the buffer is filled to capacity, subsequent string operations
will read past the buffer boundary searching for a null terminator.

In procfs_is_workload_pid(), explicitly set buffer[MAX_PATH-1] to '\0'
to ensure the buffer is always null-terminated before passing it to
strncmp(). In get_self_cgroup(), use memset() to zero the path buffer
before reading, which ensures null termination when retval is less than
MAX_PATH. Additionally, set path[MAX_PATH-1] to '\0' after the read to
handle the case where the buffer is filled completely.

These defensive buffer handling practices prevent potential buffer
overruns and align with the ongoing buffer safety improvements across
the rtla codebase.

Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260106133655.249887-17-wander@redhat.com
Signed-off-by: Tomas Glozar

rtla: Make stop_tracing variable volatile

2026-01-07T14:57:55+00:00

The stop_tracing global variable is accessed from both the signal
handler context and the main program flow without synchronization.
This creates a potential race condition where compiler optimizations
could cache the variable value in registers, preventing the signal
handler's updates from being visible to other parts of the program.

Add the volatile qualifier to stop_tracing in both common.c and
common.h to ensure all accesses to this variable bypass compiler
optimizations and read directly from memory. This guarantees that
when the signal handler sets stop_tracing, the change is immediately
visible to the main program loop, preventing potential hangs or
delayed shutdown when termination signals are received.

Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260106133655.249887-16-wander@redhat.com
Signed-off-by: Tomas Glozar

rtla: Add generated output files to gitignore

2026-01-07T14:57:55+00:00

The rtla tool generates various output files during testing and
execution, including custom trace outputs and histogram data. These
files are artifacts of running the tool with different options and
should not be tracked in version control.

Add gitignore entries for custom_filename.txt, osnoise_irq_noise_hist.txt,
osnoise_trace.txt, and timerlat_trace.txt to prevent accidentally
committing these generated files. This aligns with the existing pattern
of ignoring build artifacts and generated headers like *.skel.h.

Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260106133655.249887-15-wander@redhat.com
Signed-off-by: Tomas Glozar

rtla: Fix NULL pointer dereference in actions_parse

2026-01-07T14:57:55+00:00

The actions_parse() function uses strtok() to tokenize the trigger
string, but does not check if the returned token is NULL before
passing it to strcmp(). If the trigger parameter is an empty string
or contains only delimiter characters, strtok() returns NULL, causing
strcmp() to dereference a NULL pointer and crash the program.

This issue can be triggered by malformed user input or edge cases in
trigger string parsing. Add a NULL check immediately after the strtok()
call to validate that a token was successfully extracted before using
it. If no token is found, the function now returns -1 to indicate a
parsing error.

Signed-off-by: Wander Lairson Costa 
Link: https://lore.kernel.org/r/20260106133655.249887-13-wander@redhat.com
Signed-off-by: Tomas Glozar