On Thu, 1 Oct 2020 09:56:41 +0100 Colin King colin.king@canonical.com wrote:
From: Colin Ian King colin.king@canonical.com
More recent libc implementations are now using openat/openat2 system calls so also add do_sys_openat2 to the tracing so that the test passes on these systems because do_sys_open may not be called.
Signed-off-by: Colin Ian King colin.king@canonical.com
.../testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc index a30a9c07290d..cf1b4c3e9e6b 100644 --- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc +++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc @@ -9,6 +9,8 @@ grep -A10 "fetcharg:" README | grep -q '[u]<offset>' || exit_unsupported :;: "user-memory access syntax and ustring working on user memory";: echo 'p:myevent do_sys_open path=+0($arg2):ustring path2=+u0($arg2):string' \
kprobe_events
OK, at first, you need to check the kernel has do_sys_openat2 from /proc/kallsyms (grep -qw will help you), because it is new syscall.
+echo 'p:myevent2 do_sys_openat2 path=+0($arg2):ustring path2=+u0($arg2):string' \
Also, you need to append (">>") it instead overwrite (">") to kprobe_events.
grep myevent kprobe_events | \ grep -q 'path=+0($arg2):ustring path2=+u0($arg2):string'
And also you have to enable both myevent and myevent2 (if exists) after this.
Then I think your patch will work correctly.
Thank you!