This new test makes sure that ftrace can trace a function that was introduced by a livepatch.

Signed-off-by: Filipe Xavier felipeaggger@gmail.com --- 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 +# - unload livepatch and reset trace + +start_test "livepatch trace patched function and check that the live patch remains in effect" + +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 "" > $TRACE_FILE + +if [[ "$(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,