Em 07/01/2025 13:23, Joe Lawrence escreveu:
On Thu, Jan 02, 2025 at 03:42:10PM -0300, Filipe Xavier wrote:
This new test makes sure that ftrace can trace a
function that was introduced by a livepatch.
Hi Filipe,
Thanks for adding a test!
Aside: another similar test could verify that the original function, in
this case cmdline_proc_show(), can still be traced despite it being
livepatched. That may be non-intuitive but it demonstrates how the
ftrace handler works.
Thanks for the review Joe!
I have fixed all points mentioned below,
and have a patch ready to submit.
Do you believe that this other similar test could be sent later,
or is it required in this patch?
Signed-off-by: Filipe Xavier <felipeaggger@xxxxxxxxx>
---
tools/testing/selftests/livepatch/test-ftrace.sh | 37 ++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh b/tools/testing/selftests/livepatch/test-ftrace.sh
index fe14f248913acbec46fb6c0fec38a2fc84209d39..5f0d5308c88669e84210393ce7b8aa138b694ebd 100755
--- a/tools/testing/selftests/livepatch/test-ftrace.sh
+++ b/tools/testing/selftests/livepatch/test-ftrace.sh
@@ -61,4 +61,41 @@ livepatch: '$MOD_LIVEPATCH': unpatching complete
% rmmod $MOD_LIVEPATCH"
+# - verify livepatch can load
+# - check traces if have a patched function
nit: wording? "check if traces have a patched function" ?
+# - unload livepatch and reset trace
+
+start_test "livepatch trace patched function and check that the live patch remains in effect"
nit: wording? "trace livepatched function and check ..." ?
+
+TRACE_FILE="$SYSFS_DEBUG_DIR/tracing/trace"
+FUNCTION_NAME="livepatch_cmdline_proc_show"
+
+load_lp $MOD_LIVEPATCH
+
+echo $FUNCTION_NAME > $SYSFS_DEBUG_DIR/tracing/set_ftrace_filter
+echo "function" > $SYSFS_DEBUG_DIR/tracing/current_tracer
+echo "" > $TRACE_FILE
A few suggestions:
- The tracing is also dependent on the 'tracing_on' file, so if it
happens to be turned off, the test will fail.
- See functions.sh :: push_config() and pop_config() for an example of
saving the existing values rather than turning them all off at the end
of the test.
- Nitpick: shellcheck suggests wrapping filenames in double quotations,
applicable in several places.
+
+if [[ "$(cat /proc/cmdline)" != "$MOD_LIVEPATCH: this has been live patched" ]] ; then
+ echo -e "FAIL\n\n"
+ die "livepatch kselftest(s) failed"
+fi
+
+grep -q $FUNCTION_NAME $TRACE_FILE
+FOUND=$?
+
+disable_lp $MOD_LIVEPATCH
+unload_lp $MOD_LIVEPATCH
+
+# Reset tracing
+echo "nop" > $SYSFS_DEBUG_DIR/tracing/current_tracer
+echo "" > $SYSFS_DEBUG_DIR/tracing/set_ftrace_filter
+echo "" > $TRACE_FILE
+
+if [ "$FOUND" -eq 1 ]; then
+ echo -e "FAIL\n\n"
+ die "livepatch kselftest(s) failed"
+fi
+
+
exit 0
---
base-commit: fc033cf25e612e840e545f8d5ad2edd6ba613ed5
change-id: 20250101-ftrace-selftest-livepatch-161fb77dbed8
Best regards,
--
Filipe Xavier <felipeaggger@xxxxxxxxx>
Thanks,
--
Joe
