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,
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.
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 $MOD_LIVEPATCH" +# - verify livepatch can load +# - check traces if have a patched function
nit: wording? "check if traces have a patched function" ?
+# - unload livepatch and reset trace
+start_test "livepatch trace patched function and check that the live patch remains in effect"
nit: wording? "trace livepatched function and check ..." ?
+TRACE_FILE="$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@gmail.com
Thanks, -- Joe
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@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 $MOD_LIVEPATCH" +# - verify livepatch can load +# - check traces if have a patched function
nit: wording? "check if traces have a patched function" ?
+# - unload livepatch and reset trace
+start_test "livepatch trace patched function and check that the live patch remains in effect"
nit: wording? "trace livepatched function and check ..." ?
+TRACE_FILE="$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@gmail.com
Thanks,
Joe
On 1/10/25 12:13, Filipe Xavier wrote:
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?
The second test could be added later if you like, either way is fine w/me.
Thanks,
linux-kselftest-mirror@lists.linaro.org
-
Filipe Xavier -
Joe Lawrence