On Thu, 17 Apr 2025 22:33:23 -0400 Steven Rostedt rostedt@goodmis.org wrote:

From: Steven Rostedt rostedt@goodmis.org

Running the following commands was broken:

# cd /sys/kernel/tracing # echo "filename.ustring ~ "/proc*"" > events/syscalls/sys_enter_openat/filter # echo 1 > events/syscalls/sys_enter_openat/enable # ls /proc/$$/maps # cat trace

And would produce nothing when it should have produced something like:

  ls-1192    [007] .....  8169.828333: sys_openat(dfd: ffffffffffffff9c, filename: 7efc18359904, flags: 80000, mode: 0)

Add a test to check this case so that it will be caught if it breaks again.

Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org

Shuah, I'm Cc'ing you on this for your information, but I'll take it through my tree as it will be attached with the fix, as it will fail without it.

.../test.d/filter/event-filter-function.tc | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)

diff --git a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc index 118247b8dd84..ab449a2cea8c 100644 --- a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc +++ b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc @@ -80,6 +80,25 @@ if [ $misscnt -gt 0 ]; then exit_fail fi +# Check strings too +if [ -f events/syscalls/sys_enter_openat/filter ]; then

• echo "filename.ustring ~ "*test.d*"" > events/syscalls/sys_enter_openat/filter

I think it is better to use a $TMPDIR for the test script, instead of reusing the $TEST_DIR. Since $TMPDIR has been introduced to be used for this purpose.

DIRNAME=`basename $TMPDIR`

echo "filename.ustring ~ "*$DIRNAME*"" > events/syscalls/sys_enter_openat/filter

• echo 1 > events/syscalls/sys_enter_openat/enable
• echo 1 > tracing_on
• ls /bin/sh
• nocnt=`grep openat trace | wc -l`
• ls $TEST_DIR

and `ls $TMPDIR` ?

Does that work?

Thank you,

• echo 0 > tracing_on
• hitcnt=`grep openat trace | wc -l`;
• echo 0 > events/syscalls/sys_enter_openat/enable
• if [ $nocnt -gt 0 ]; then

• exit_fail
  

• fi
• if [ $hitcnt -eq 0 ]; then

• exit_fail
  

• fi

+fi

reset_events_filter exit 0 -- 2.47.2