| Message ID | 20250111-ftrace-selftest-livepatch-v2-1-9f4ff90f251a@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] selftests: livepatch: test if ftrace can trace a livepatched function | expand |
On Sat, 2025-01-11 at 15:42 -0300, Filipe Xavier wrote: > 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> Thanks for the new test Filipe! I have some nits below, but these don't need to be addressed for the test to be merged. Either way, Reviewed-by: Marcos Paulo de Souza <mpdesouza@suse.com> Tested-by: Marcos Paulo de Souza <mpdesouza@suse.com> > --- > Changes in v2: > - functions.sh: added reset tracing on push and pop_config. > - test-ftrace.sh: enabled tracing_on before test init. > - nitpick: added double quotations on filenames and fixed some > wording. > - Link to v1: > https://lore.kernel.org/r/20250102-ftrace-selftest-livepatch-v1-1-84880baefc1b@gmail.com > --- > tools/testing/selftests/livepatch/functions.sh | 14 ++++++++++ > tools/testing/selftests/livepatch/test-ftrace.sh | 33 > ++++++++++++++++++++++++ > 2 files changed, 47 insertions(+) > > diff --git a/tools/testing/selftests/livepatch/functions.sh > b/tools/testing/selftests/livepatch/functions.sh > index > e5d06fb402335d85959bafe099087effc6ddce12..e6c13514002dae5f8d7461f90b8 > 241ab43024ea4 100644 > --- a/tools/testing/selftests/livepatch/functions.sh > +++ b/tools/testing/selftests/livepatch/functions.sh > @@ -62,6 +62,9 @@ function push_config() { > awk -F'[: ]' '{print "file " $1 " line " $2 > " " $4}') > FTRACE_ENABLED=$(sysctl --values kernel.ftrace_enabled) > KPROBE_ENABLED=$(cat "$SYSFS_KPROBES_DIR/enabled") > + TRACING_ON=$(cat "$SYSFS_DEBUG_DIR/tracing/tracing_on") > + CURRENT_TRACER=$(cat > "$SYSFS_DEBUG_DIR/tracing/current_tracer") > + FTRACE_FILTER=$(cat > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter") > } > > function pop_config() { > @@ -74,6 +77,17 @@ function pop_config() { > if [[ -n "$KPROBE_ENABLED" ]]; then > echo "$KPROBE_ENABLED" > > "$SYSFS_KPROBES_DIR/enabled" > fi > + if [[ -n "$TRACING_ON" ]]; then > + echo "$TRACING_ON" > > "$SYSFS_DEBUG_DIR/tracing/tracing_on" > + fi > + if [[ -n "$CURRENT_TRACER" ]]; then > + echo "$CURRENT_TRACER" > > "$SYSFS_DEBUG_DIR/tracing/current_tracer" > + fi > + if [[ "$FTRACE_FILTER" == *"#"* ]]; then > + echo > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" > + elif [[ -n "$FTRACE_FILTER" ]]; then > + echo "$FTRACE_FILTER" > > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" > + fi > } I believe that this could be a separate patch, since this is new functionality that's being added to functions.sh, and not exactly related to the new test. > > function set_dynamic_debug() { > diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh > b/tools/testing/selftests/livepatch/test-ftrace.sh > index > fe14f248913acbec46fb6c0fec38a2fc84209d39..66af5d726c52e48e5177804e182 > b4ff31784d5ac 100755 > --- a/tools/testing/selftests/livepatch/test-ftrace.sh > +++ b/tools/testing/selftests/livepatch/test-ftrace.sh > @@ -61,4 +61,37 @@ livepatch: '$MOD_LIVEPATCH': unpatching complete > % rmmod $MOD_LIVEPATCH" > > > +# - verify livepatch can load > +# - check if traces have a patched function > +# - unload livepatch and reset trace > + > +start_test "trace livepatched function and check that the live patch > remains in effect" > + > +TRACE_FILE="$SYSFS_DEBUG_DIR/tracing/trace" > +FUNCTION_NAME="livepatch_cmdline_proc_show" > + > +load_lp $MOD_LIVEPATCH > + > +echo 1 > "$SYSFS_DEBUG_DIR/tracing/tracing_on" > +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 $MOD_LIVEPATCH > + > +if [ "$FOUND" -eq 1 ]; then > + echo -e "FAIL\n\n" > + die "livepatch kselftest(s) failed" > +fi > + > + > exit 0 The test works, and that's very cool. But when running locally, I find the if we miss check_result call it doesn't add a newline after the "ok": ... # timeout set to 0 # selftests: livepatch: test-ftrace.sh # TEST: livepatch interaction with ftrace_enabled sysctl ... ok # TEST: trace livepatched function and check that the live patch remains in effect ... ok 5 selftests: livepatch: test-ftrace.sh # timeout set to 0 # selftests: livepatch: test-sysfs.sh ... If the check_result below is added the output if sane again: ... # selftests: livepatch: test-ftrace.sh # TEST: livepatch interaction with ftrace_enabled sysctl ... ok # TEST: trace livepatched function and check that the live patch remains in effect ... ok ok 5 selftests: livepatch: test-ftrace.sh ... I checked and this would be the only one test without using check_result, so maybe we should add this either way? I'm not sure what you guys think about it. diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh b/tools/testing/selftests/livepatch/test-ftrace.sh index 66af5d726c52..135c0fb17a98 100755 --- a/tools/testing/selftests/livepatch/test-ftrace.sh +++ b/tools/testing/selftests/livepatch/test-ftrace.sh @@ -93,5 +93,18 @@ if [ "$FOUND" -eq 1 ]; then die "livepatch kselftest(s) failed" fi +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +livepatch: '$MOD_LIVEPATCH': patching complete +% echo 0 > $SYSFS_KLP_DIR/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH" + exit 0 > > --- > base-commit: fc033cf25e612e840e545f8d5ad2edd6ba613ed5 > change-id: 20250101-ftrace-selftest-livepatch-161fb77dbed8 > > Best regards,
On 1/14/25 12:18, Marcos Paulo de Souza wrote: > On Sat, 2025-01-11 at 15:42 -0300, Filipe Xavier wrote: >> 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> > > Thanks for the new test Filipe! > > I have some nits below, but these don't need to be addressed for the > test to be merged. Either way, > > Reviewed-by: Marcos Paulo de Souza <mpdesouza@suse.com> > Tested-by: Marcos Paulo de Souza <mpdesouza@suse.com> > > > >> --- >> Changes in v2: >> - functions.sh: added reset tracing on push and pop_config. >> - test-ftrace.sh: enabled tracing_on before test init. >> - nitpick: added double quotations on filenames and fixed some >> wording. >> - Link to v1: >> https://lore.kernel.org/r/20250102-ftrace-selftest-livepatch-v1-1-84880baefc1b@gmail.com >> --- >> tools/testing/selftests/livepatch/functions.sh | 14 ++++++++++ >> tools/testing/selftests/livepatch/test-ftrace.sh | 33 >> ++++++++++++++++++++++++ >> 2 files changed, 47 insertions(+) >> >> diff --git a/tools/testing/selftests/livepatch/functions.sh >> b/tools/testing/selftests/livepatch/functions.sh >> index >> e5d06fb402335d85959bafe099087effc6ddce12..e6c13514002dae5f8d7461f90b8 >> 241ab43024ea4 100644 >> --- a/tools/testing/selftests/livepatch/functions.sh >> +++ b/tools/testing/selftests/livepatch/functions.sh >> @@ -62,6 +62,9 @@ function push_config() { >> awk -F'[: ]' '{print "file " $1 " line " $2 >> " " $4}') >> FTRACE_ENABLED=$(sysctl --values kernel.ftrace_enabled) >> KPROBE_ENABLED=$(cat "$SYSFS_KPROBES_DIR/enabled") >> + TRACING_ON=$(cat "$SYSFS_DEBUG_DIR/tracing/tracing_on") >> + CURRENT_TRACER=$(cat >> "$SYSFS_DEBUG_DIR/tracing/current_tracer") >> + FTRACE_FILTER=$(cat >> "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter") >> } >> >> function pop_config() { >> @@ -74,6 +77,17 @@ function pop_config() { >> if [[ -n "$KPROBE_ENABLED" ]]; then >> echo "$KPROBE_ENABLED" > >> "$SYSFS_KPROBES_DIR/enabled" >> fi >> + if [[ -n "$TRACING_ON" ]]; then >> + echo "$TRACING_ON" > >> "$SYSFS_DEBUG_DIR/tracing/tracing_on" >> + fi >> + if [[ -n "$CURRENT_TRACER" ]]; then >> + echo "$CURRENT_TRACER" > >> "$SYSFS_DEBUG_DIR/tracing/current_tracer" >> + fi >> + if [[ "$FTRACE_FILTER" == *"#"* ]]; then >> + echo > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" >> + elif [[ -n "$FTRACE_FILTER" ]]; then >> + echo "$FTRACE_FILTER" > >> "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" >> + fi >> } > > I believe that this could be a separate patch, since this is new > functionality that's being added to functions.sh, and not exactly > related to the new test. > >> >> function set_dynamic_debug() { >> diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh >> b/tools/testing/selftests/livepatch/test-ftrace.sh >> index >> fe14f248913acbec46fb6c0fec38a2fc84209d39..66af5d726c52e48e5177804e182 >> b4ff31784d5ac 100755 >> --- a/tools/testing/selftests/livepatch/test-ftrace.sh >> +++ b/tools/testing/selftests/livepatch/test-ftrace.sh >> @@ -61,4 +61,37 @@ livepatch: '$MOD_LIVEPATCH': unpatching complete >> % rmmod $MOD_LIVEPATCH" >> >> >> +# - verify livepatch can load >> +# - check if traces have a patched function >> +# - unload livepatch and reset trace >> + >> +start_test "trace livepatched function and check that the live patch >> remains in effect" >> + >> +TRACE_FILE="$SYSFS_DEBUG_DIR/tracing/trace" >> +FUNCTION_NAME="livepatch_cmdline_proc_show" >> + >> +load_lp $MOD_LIVEPATCH >> + >> +echo 1 > "$SYSFS_DEBUG_DIR/tracing/tracing_on" >> +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 $MOD_LIVEPATCH >> + >> +if [ "$FOUND" -eq 1 ]; then >> + echo -e "FAIL\n\n" >> + die "livepatch kselftest(s) failed" >> +fi >> + >> + >> exit 0 > > The test works, and that's very cool. But when running locally, I find > the if we miss check_result call it doesn't add a newline after the > "ok": > > ... > # timeout set to 0 > # selftests: livepatch: test-ftrace.sh > # TEST: livepatch interaction with ftrace_enabled sysctl ... ok > # TEST: trace livepatched function and check that the live patch > remains in effect ... ok 5 selftests: livepatch: test-ftrace.sh > # timeout set to 0 > # selftests: livepatch: test-sysfs.sh > ... > > If the check_result below is added the output if sane again: > > ... > # selftests: livepatch: test-ftrace.sh > # TEST: livepatch interaction with ftrace_enabled sysctl ... ok > # TEST: trace livepatched function and check that the live patch > remains in effect ... ok > ok 5 selftests: livepatch: test-ftrace.sh > ... > > I checked and this would be the only one test without using > check_result, so maybe we should add this either way? I'm not sure what > you guys think about it. > > > diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh > b/tools/testing/selftests/livepatch/test-ftrace.sh > index 66af5d726c52..135c0fb17a98 100755 > --- a/tools/testing/selftests/livepatch/test-ftrace.sh > +++ b/tools/testing/selftests/livepatch/test-ftrace.sh > @@ -93,5 +93,18 @@ if [ "$FOUND" -eq 1 ]; then > die "livepatch kselftest(s) failed" > fi > > +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko > +livepatch: enabling patch '$MOD_LIVEPATCH' > +livepatch: '$MOD_LIVEPATCH': initializing patching transition > +livepatch: '$MOD_LIVEPATCH': starting patching transition > +livepatch: '$MOD_LIVEPATCH': completing patching transition > +livepatch: '$MOD_LIVEPATCH': patching complete > +% echo 0 > $SYSFS_KLP_DIR/$MOD_LIVEPATCH/enabled > +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition > +livepatch: '$MOD_LIVEPATCH': starting unpatching transition > +livepatch: '$MOD_LIVEPATCH': completing unpatching transition > +livepatch: '$MOD_LIVEPATCH': unpatching complete > +% rmmod $MOD_LIVEPATCH" > + > Ah good catch, I noticed the newline, too, but didn't notice that the test wasn't using check_result(). For consistency, let's make that change before merging. Thanks,
Hi Filipe, first, thanks for the test. It is good. I just suggest a lot of clean up ;-) On Sat 2025-01-11 15:42:27, Filipe Xavier wrote: > This new test makes sure that ftrace can trace a > function that was introduced by a livepatch. > --- > Changes in v2: > - functions.sh: added reset tracing on push and pop_config. > - test-ftrace.sh: enabled tracing_on before test init. > - nitpick: added double quotations on filenames and fixed some wording. > - Link to v1: https://lore.kernel.org/r/20250102-ftrace-selftest-livepatch-v1-1-84880baefc1b@gmail.com > --- > tools/testing/selftests/livepatch/functions.sh | 14 ++++++++++ > tools/testing/selftests/livepatch/test-ftrace.sh | 33 ++++++++++++++++++++++++ > 2 files changed, 47 insertions(+) > > diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh > index e5d06fb402335d85959bafe099087effc6ddce12..e6c13514002dae5f8d7461f90b8241ab43024ea4 100644 > --- a/tools/testing/selftests/livepatch/functions.sh > +++ b/tools/testing/selftests/livepatch/functions.sh > @@ -62,6 +62,9 @@ function push_config() { > awk -F'[: ]' '{print "file " $1 " line " $2 " " $4}') > FTRACE_ENABLED=$(sysctl --values kernel.ftrace_enabled) > KPROBE_ENABLED=$(cat "$SYSFS_KPROBES_DIR/enabled") > + TRACING_ON=$(cat "$SYSFS_DEBUG_DIR/tracing/tracing_on") The $SYSFS_DEBUG_DIR/tracing directory is used many times. It would make sense to define: SYSFS_TRACING_DIR="$SYSFS_DEBUG_DIR/tracing" and use: TRACING_ON=$(cat "$SYSFS_TRACING_DIR/tracing_on") > + CURRENT_TRACER=$(cat "$SYSFS_DEBUG_DIR/tracing/current_tracer") > + FTRACE_FILTER=$(cat "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter") > } > > function pop_config() { > @@ -74,6 +77,17 @@ function pop_config() { > if [[ -n "$KPROBE_ENABLED" ]]; then > echo "$KPROBE_ENABLED" > "$SYSFS_KPROBES_DIR/enabled" > fi > + if [[ -n "$TRACING_ON" ]]; then > + echo "$TRACING_ON" > "$SYSFS_DEBUG_DIR/tracing/tracing_on" > + fi > + if [[ -n "$CURRENT_TRACER" ]]; then > + echo "$CURRENT_TRACER" > "$SYSFS_DEBUG_DIR/tracing/current_tracer" > + fi > + if [[ "$FTRACE_FILTER" == *"#"* ]]; then > + echo > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" My understanding is that this is handling the situation when the filter is: #### all functions enabled #### I was curious about the pattern *"#"*. The quotation looked pretty non-standard to me. It made me to read the bash documentation and the rules for extressions in [[ ]] looked quite complicated. I wonder if we could make this more for "dummies". The following seems to work: if [[ -n "$FTRACE_FILTER" ]]; then echo "$FTRACE_FILTER" | sed -e "/#### all functions enabled ####/d" > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" fi Note that the string "#### all functions enabled ####" is a very stable thing. It has never been modified since it was introduced by the commit 0c75a3ed633419d75d ("ftrace: state that all functions are enabled in set_ftrace_filter") in Feb 2009. The string is used also in ftrace selftests, see tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc > + elif [[ -n "$FTRACE_FILTER" ]]; then > + echo "$FTRACE_FILTER" > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" > + fi > } > > function set_dynamic_debug() { > diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh b/tools/testing/selftests/livepatch/test-ftrace.sh > index fe14f248913acbec46fb6c0fec38a2fc84209d39..66af5d726c52e48e5177804e182b4ff31784d5ac 100755 > --- a/tools/testing/selftests/livepatch/test-ftrace.sh > +++ b/tools/testing/selftests/livepatch/test-ftrace.sh > @@ -61,4 +61,37 @@ livepatch: '$MOD_LIVEPATCH': unpatching complete > % rmmod $MOD_LIVEPATCH" > > > +# - verify livepatch can load > +# - check if traces have a patched function > +# - unload livepatch and reset trace > + > +start_test "trace livepatched function and check that the live patch remains in effect" > + > +TRACE_FILE="$SYSFS_DEBUG_DIR/tracing/trace" > +FUNCTION_NAME="livepatch_cmdline_proc_show" > + > +load_lp $MOD_LIVEPATCH > + > +echo 1 > "$SYSFS_DEBUG_DIR/tracing/tracing_on" > +echo $FUNCTION_NAME > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" The above mentioned ftrace selftest shows that the behavior gets more complicated when "traceoff" is used: 1. The "traceoff" entries are not cleared by the above command. 2. The "traceoff" entries might cause that the tracing will stop before we finish this test. > +echo "function" > "$SYSFS_DEBUG_DIR/tracing/current_tracer" > +echo "" > "$TRACE_FILE" I suggest to change the ordering and make sure that nothing is running before we start: # Start with the clean up echo 0 > "$SYSFS_TRACING_DIR/tracing_on" echo '!*:traceoff' > $SYSFS_TRACING_DIR/set_ftrace_filter echo "" > "$SYSFS_TRACING_DIR/current_tracer" echo "" > $SYSFS_TRACING_DIR/trace # Setup and start our tracing echo "function" > "$SYSFS_TRACING_DIR/current_tracer" echo $FUNCTION_NAME > "$SYSFS_TRACING_DIR/set_ftrace_filter" echo 1 > "$SYSFS_TRACING_DIR/tracing_on" I suggest to this into helper functions which might be used by more tests: # cleanup_tracing() - stop and clean up function tracing function cleanup_tracing() { echo 0 > "$SYSFS_TRACING_DIR/tracing_on" echo '!*:traceoff' > $SYSFS_TRACING_DIR/set_ftrace_filter echo "" > "$SYSFS_TRACING_DIR/current_tracer" echo "" > $SYSFS_TRACING_DIR/trace } # trace_function(function) - start tracing of a function # function - to be traced function function trace_function() { local function="$1"; shift cleanup_tracing echo "function" > "$SYSFS_TRACING_DIR/current_tracer" echo "$functions" > $SYSFS_TRACING_DIR/set_ftrace_filter echo 1 > "$SYSFS_TRACING_DIR/tracing_on" } # check_traced_function(function) - check whether function appeared in trace log # function - to be traced function function check_trace_function() { local function="$1"; shift if ! grep -q "$function" $SYSFS_TRACING_DIR/trace" ; then die "Function ($function) did not appear in the trace" fi } As Marcos suggested, it would make sense to add the above mentioned helper functions in a separate patch. > + > +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=$? We could replace this with the above proposed check_traced_function "$FUNCTION_NAME" Also I would personally stop the tracing after this sub-test finishes. We might use the cleanup_tracing function here. cleanup_tracing > + > +disable_lp $MOD_LIVEPATCH > +unload_lp $MOD_LIVEPATCH > + > +if [ "$FOUND" -eq 1 ]; then > + echo -e "FAIL\n\n" > + die "livepatch kselftest(s) failed" > +fi As mentioned by Marcos, we should also print "ok" on success. I would personally use the "check_result" function here. It could catch non-expected entries in dmesg. > + > exit 0 Best Regards, Petr
diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh index e5d06fb402335d85959bafe099087effc6ddce12..e6c13514002dae5f8d7461f90b8241ab43024ea4 100644 --- a/tools/testing/selftests/livepatch/functions.sh +++ b/tools/testing/selftests/livepatch/functions.sh @@ -62,6 +62,9 @@ function push_config() { awk -F'[: ]' '{print "file " $1 " line " $2 " " $4}') FTRACE_ENABLED=$(sysctl --values kernel.ftrace_enabled) KPROBE_ENABLED=$(cat "$SYSFS_KPROBES_DIR/enabled") + TRACING_ON=$(cat "$SYSFS_DEBUG_DIR/tracing/tracing_on") + CURRENT_TRACER=$(cat "$SYSFS_DEBUG_DIR/tracing/current_tracer") + FTRACE_FILTER=$(cat "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter") } function pop_config() { @@ -74,6 +77,17 @@ function pop_config() { if [[ -n "$KPROBE_ENABLED" ]]; then echo "$KPROBE_ENABLED" > "$SYSFS_KPROBES_DIR/enabled" fi + if [[ -n "$TRACING_ON" ]]; then + echo "$TRACING_ON" > "$SYSFS_DEBUG_DIR/tracing/tracing_on" + fi + if [[ -n "$CURRENT_TRACER" ]]; then + echo "$CURRENT_TRACER" > "$SYSFS_DEBUG_DIR/tracing/current_tracer" + fi + if [[ "$FTRACE_FILTER" == *"#"* ]]; then + echo > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" + elif [[ -n "$FTRACE_FILTER" ]]; then + echo "$FTRACE_FILTER" > "$SYSFS_DEBUG_DIR/tracing/set_ftrace_filter" + fi } function set_dynamic_debug() { diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh b/tools/testing/selftests/livepatch/test-ftrace.sh index fe14f248913acbec46fb6c0fec38a2fc84209d39..66af5d726c52e48e5177804e182b4ff31784d5ac 100755 --- a/tools/testing/selftests/livepatch/test-ftrace.sh +++ b/tools/testing/selftests/livepatch/test-ftrace.sh @@ -61,4 +61,37 @@ livepatch: '$MOD_LIVEPATCH': unpatching complete % rmmod $MOD_LIVEPATCH" +# - verify livepatch can load +# - check if traces have a patched function +# - unload livepatch and reset trace + +start_test "trace livepatched function and check that the live patch remains in effect" + +TRACE_FILE="$SYSFS_DEBUG_DIR/tracing/trace" +FUNCTION_NAME="livepatch_cmdline_proc_show" + +load_lp $MOD_LIVEPATCH + +echo 1 > "$SYSFS_DEBUG_DIR/tracing/tracing_on" +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 $MOD_LIVEPATCH + +if [ "$FOUND" -eq 1 ]; then + echo -e "FAIL\n\n" + die "livepatch kselftest(s) failed" +fi + + exit 0
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> --- Changes in v2: - functions.sh: added reset tracing on push and pop_config. - test-ftrace.sh: enabled tracing_on before test init. - nitpick: added double quotations on filenames and fixed some wording. - Link to v1: https://lore.kernel.org/r/20250102-ftrace-selftest-livepatch-v1-1-84880baefc1b@gmail.com --- tools/testing/selftests/livepatch/functions.sh | 14 ++++++++++ tools/testing/selftests/livepatch/test-ftrace.sh | 33 ++++++++++++++++++++++++ 2 files changed, 47 insertions(+) --- base-commit: fc033cf25e612e840e545f8d5ad2edd6ba613ed5 change-id: 20250101-ftrace-selftest-livepatch-161fb77dbed8 Best regards,