It may lead to kernel panic when execute the following testcase on mips: # cd tools/testing/selftests/ftrace # ./ftracetest test.d/kprobe/multiple_kprobes.tc A preliminary analysis shows that the issue is related with echo 1 > events/kprobes/enable after add the 256 probe points. In order to find the root cause, I want to verify which probe point has problem, so it is necessary to save kprobe_events to test log. With this patch, we can get the 256 probe points in the test log through the following command: # ./ftracetest test.d/kprobe/multiple_kprobes.tc -vvv -k Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> --- tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc index 312d237..be754f5 100644 --- a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc +++ b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc @@ -25,6 +25,8 @@ if [ $L -ne 256 ]; then exit_fail fi +cat kprobe_events >> $testlog + echo 1 > events/kprobes/enable echo 0 > events/kprobes/enable echo > kprobe_events -- 2.1.0