kernel/linux.git/tools/tracing, branch v6.19.11

rtla: Fix NULL pointer dereference in actions_parse

2026-03-04T12:20:21+00:00

[ Upstream commit a0890f9dbd24b302d327fe7dad9b9c5be0e278aa ] 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 Signed-off-by: Sasha Levin

Merge tag 'trace-tools-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2025-12-05T17:34:01+00:00

Pull rtla trace tooling updates from Steven Rostedt: - Officially add Tomas Glozar as a maintainer to RTLA tool - Add for_each_monitored_cpu() helper In multiple places, RTLA tools iterate over the list of CPUs running tracer threads. Use single helper instead of repeating the for/if combination. - Remove unused variable option_index in argument parsing RTLA tools use getopt_long() for argument parsing. For its last argument, an unused variable "option_index" is passed. Remove the variable and pass NULL to getopt_long() to shorten the naturally long parsing functions, and make them more readable. - Fix unassigned nr_cpus after code consolidation In recent code consolidation, timerlat tool cleanup, previously implemented separately for each tool, was moved to a common function timerlat_free(). The cleanup relies on nr_cpus being set. This was not done in the new function, leaving the variable uninitialized. Initialize the variable properly, and remove silencing of compiler warning for uninitialized variables. - Stop tracing on user latency in BPF mode Despite the name, rtla-timerlat's -T/--thread option sets timerlat's stop_tracing_total_us option, which also stops tracing on return-from-user latency, not only on thread latency. Implement the same behavior also in BPF sample collection stop tracing handler to avoid a discrepancy and restore correspondence of behavior with the equivalent option of cyclictest. - Fix threshold actions always triggering A bug in threshold action logic caused the action to execute even if tracing did not stop because of threshold. Fix the logic to stop correctly. - Fix few minor issues in tests Extend tests that were shown to need it to 5s, fix osnoise test calling timerlat by mistake, and use new, more reliable output checking in timerlat's "top stop at failed action" test. - Do not print usage on argument parsing error RTLA prints the entire usage message on encountering errors in argument parsing, like a malformed CPU list. The usage message has gotten too long. Instead of printing it, use newly added fatal() helper function to simply exit with the error message, excluding the usage. - Fix unintuitive -C/--cgroup interface "-C cgroup" and "--cgroup cgroup" are invalid syntax, despite that being a common way to specify an option with argument. Moreover, using them fails silently and no cgroup is set. Create new helper function to unify the handling of all such options and allow all of: -Xsomething -X=something -X something as well as the equivalent for the long option. - Fix -a overriding -t argument filename Fix a bug where -a following -t custom_file.txt overrides the custom filename with the default timerlat_trace.txt. - Stop tracing correctly on multiple events at once In some race scenarios, RTLA BPF sample collection might send multiple stop tracing events via the BPF ringbuffer at once. Compare the number of events for != 0 instead of == 1 to cover for this scenario and stop tracing properly. * tag 'trace-tools-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: rtla/timerlat: Exit top main loop on any non-zero wait_retval rtla/tests: Don't rely on matching ^1ALL rtla: Fix -a overriding -t argument rtla: Fix -C/--cgroup interface tools/rtla: Replace osnoise_hist_usage("...") with fatal("...") tools/rtla: Replace osnoise_top_usage("...") with fatal("...") tools/rtla: Replace timerlat_hist_usage("...") with fatal("...") tools/rtla: Replace timerlat_top_usage("...") with fatal("...") tools/rtla: Add fatal() and replace error handling pattern rtla/tests: Fix osnoise test calling timerlat rtla/tests: Extend action tests to 5s tools/rtla: Fix --on-threshold always triggering rtla/timerlat_bpf: Stop tracing on user latency tools/rtla: Fix unassigned nr_cpus tools/rtla: Remove unused optional option_index tools/rtla: Add for_each_monitored_cpu() helper MAINTAINERS: Add Tomas Glozar as a maintainer to RTLA tool

rtla/timerlat: Exit top main loop on any non-zero wait_retval

2025-11-21T09:30:27+00:00

Comparing to exactly 1 will fail if more than one ring buffer event was seen since the last call to timerlat_bpf_wait(), which can happen in some race scenarios. Signed-off-by: Crystal Wood Link: https://lore.kernel.org/r/20251112152529.956778-5-crwood@redhat.com Signed-off-by: Tomas Glozar

rtla/tests: Don't rely on matching ^1ALL

2025-11-21T09:30:27+00:00

The timerlat "top stop at failed action" test was relying on "ALL" being printed immediately after the "1" from the threshold action. Besides being fragile, this depends on stdbuf behavior, which is easy to miss when recreating the test outside of the framework for debugging purposes. Instead, use the expected/unexpected text mechanism from the corresponding osnoise test. Signed-off-by: Crystal Wood Link: https://lore.kernel.org/r/20251112152529.956778-2-crwood@redhat.com Signed-off-by: Tomas Glozar

rtla: Fix -a overriding -t argument

2025-11-21T09:30:27+00:00

When running rtla as `rtla -t custom_file.txt -a 100` -a options override trace output filename specified by -t option. Running the command above will create _trace.txt file instead of custom_file.txt. Fix this by making sure that -a option does not override trace output filename even if it's passed after trace output filename is specified. Fixes: 173a3b014827 ("rtla/timerlat: Add the automatic trace option") Signed-off-by: Ivan Pravdin Reviewed-by: Tomas Glozar Link: https://lore.kernel.org/r/b6ae60424050b2c1c8709e18759adead6012b971.1762186418.git.ipravdin.official@gmail.com [ use capital letter in subject, as required by tracing subsystem ] Signed-off-by: Tomas Glozar

rtla: Fix -C/--cgroup interface

2025-11-21T09:30:27+00:00

Currently, user can only specify cgroup to the tracer's thread the following ways: `-C[cgroup]` `-C[=cgroup]` `--cgroup[=cgroup]` If user tries to specify cgroup as `-C [cgroup]` or `--cgroup [cgroup]`, the parser silently fails and rtla's cgroup is used for the tracer threads. To make interface more user-friendly, allow user to specify cgroup in the aforementioned way, i.e. `-C [cgroup]` and `--cgroup [cgroup]`. Refactor identical logic between -t/--trace and -C/--cgroup into a common function. Change documentation to reflect this user interface change. Fixes: a957cbc02531 ("rtla: Add -C cgroup support") Signed-off-by: Ivan Pravdin Reviewed-by: Tomas Glozar Link: https://lore.kernel.org/r/16132f1565cf5142b5fbd179975be370b529ced7.1762186418.git.ipravdin.official@gmail.com [ use capital letter in subject, as required by tracing subsystem ] Signed-off-by: Tomas Glozar

tools/rtla: Replace osnoise_hist_usage("...") with fatal("...")

2025-11-21T09:30:27+00:00

A long time ago, when the usage help was short, it was a favor to the user to show it on error. Now that the usage help has become very long, it is too noisy to dump the complete help text for each typo after the error message itself. Replace osnoise_hist_usage("...") with fatal("...") on errors. Remove the already unused 'usage' argument from osnoise_hist_usage(). Signed-off-by: Costa Shulyupin Reviewed-by: Tomas Glozar Link: https://lore.kernel.org/r/20251011082738.173670-6-costa.shul@redhat.com Signed-off-by: Tomas Glozar

tools/rtla: Replace osnoise_top_usage("...") with fatal("...")

2025-11-21T09:30:27+00:00

A long time ago, when the usage help was short, it was a favor to the user to show it on error. Now that the usage help has become very long, it is too noisy to dump the complete help text for each typo after the error message itself. Replace osnoise_top_usage("...") with fatal("...") on errors. Remove the already unused 'usage' argument from osnoise_top_usage(). Signed-off-by: Costa Shulyupin Reviewed-by: Tomas Glozar Link: https://lore.kernel.org/r/20251011082738.173670-5-costa.shul@redhat.com Signed-off-by: Tomas Glozar

tools/rtla: Replace timerlat_hist_usage("...") with fatal("...")

2025-11-21T09:30:27+00:00

A long time ago, when the usage help was short, it was a favor to the user to show it on error. Now that the usage help has become very long, it is too noisy to dump the complete help text for each typo after the error message itself. Replace timerlat_hist_usage("...\n") with fatal("...") on errors. Remove the already unused 'usage' argument from timerlat_hist_usage(). Signed-off-by: Costa Shulyupin Reviewed-by: Tomas Glozar Link: https://lore.kernel.org/r/20251011082738.173670-4-costa.shul@redhat.com Signed-off-by: Tomas Glozar

tools/rtla: Replace timerlat_top_usage("...") with fatal("...")

2025-11-21T09:30:27+00:00

A long time ago, when the usage help was short, it was a favor to the user to show it on error. Now that the usage help has become very long, it is too noisy to dump the complete help text for each typo after the error message itself. Replace timerlat_top_usage("...\n") with fatal("...") on errors. Remove the already unused 'usage' argument from timerlat_top_usage(). Signed-off-by: Costa Shulyupin Reviewed-by: Tomas Glozar Link: https://lore.kernel.org/r/20251011082738.173670-3-costa.shul@redhat.com Signed-off-by: Tomas Glozar