This is a note to let you know that I've just added the patch titled
selftests/ftrace: Choose target function for filter test from samples
to the 6.3-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
selftests-ftrace-choose-target-function-for-filter-t.patch
and it can be found in the queue-6.3 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f31f4a9d91a7a923a79ca0c60a98ad17375af3a4
Author: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Date: Sun Mar 19 11:53:32 2023 +0900
selftests/ftrace: Choose target function for filter test from samples
[ Upstream commit eb50d0f250e96ede9192d936d220cd97adc93b89 ]
Since the event-filter-function.tc expects the 'exit_mmap()' directly
calls 'kmem_cache_free()', this is vulnerable to code modifications.
Choose the target function for the filter test from the sample
event data so that it can keep test running correctly even if the caller
function name will be changed.
Link: https://lore.kernel.org/linux-trace-kernel/167919441260.1922645.18355804179347364057.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx/
Link: https://lore.kernel.org/all/CA+G9fYtF-XEKi9YNGgR=Kf==7iRb2FrmEC7qtwAeQbfyah-UhA@xxxxxxxxxxxxxx/
Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
Fixes: 7f09d639b8c4 ("tracing/selftests: Add test for event filtering on function name")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Acked-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
index e2ff3bf4df80f..2de7c61d1ae30 100644
--- a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
+++ b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
@@ -9,18 +9,33 @@ fail() { #msg
exit_fail
}
-echo "Test event filter function name"
+sample_events() {
+ echo > trace
+ echo 1 > events/kmem/kmem_cache_free/enable
+ echo 1 > tracing_on
+ ls > /dev/null
+ echo 0 > tracing_on
+ echo 0 > events/kmem/kmem_cache_free/enable
+}
+
echo 0 > tracing_on
echo 0 > events/enable
+
+echo "Get the most frequently calling function"
+sample_events
+
+target_func=`cut -d: -f3 trace | sed 's/call_site=\([^+]*\)+0x.*/\1/' | sort | uniq -c | sort | tail -n 1 | sed 's/^[ 0-9]*//'`
+if [ -z "$target_func" ]; then
+ exit_fail
+fi
echo > trace
-echo 'call_site.function == exit_mmap' > events/kmem/kmem_cache_free/filter
-echo 1 > events/kmem/kmem_cache_free/enable
-echo 1 > tracing_on
-ls > /dev/null
-echo 0 > events/kmem/kmem_cache_free/enable
-hitcnt=`grep kmem_cache_free trace| grep exit_mmap | wc -l`
-misscnt=`grep kmem_cache_free trace| grep -v exit_mmap | wc -l`
+echo "Test event filter function name"
+echo "call_site.function == $target_func" > events/kmem/kmem_cache_free/filter
+sample_events
+
+hitcnt=`grep kmem_cache_free trace| grep $target_func | wc -l`
+misscnt=`grep kmem_cache_free trace| grep -v $target_func | wc -l`
if [ $hitcnt -eq 0 ]; then
exit_fail
@@ -30,20 +45,14 @@ if [ $misscnt -gt 0 ]; then
exit_fail
fi
-address=`grep ' exit_mmap$' /proc/kallsyms | cut -d' ' -f1`
+address=`grep " ${target_func}\$" /proc/kallsyms | cut -d' ' -f1`
echo "Test event filter function address"
-echo 0 > tracing_on
-echo 0 > events/enable
-echo > trace
echo "call_site.function == 0x$address" > events/kmem/kmem_cache_free/filter
-echo 1 > events/kmem/kmem_cache_free/enable
-echo 1 > tracing_on
-sleep 1
-echo 0 > events/kmem/kmem_cache_free/enable
+sample_events
-hitcnt=`grep kmem_cache_free trace| grep exit_mmap | wc -l`
-misscnt=`grep kmem_cache_free trace| grep -v exit_mmap | wc -l`
+hitcnt=`grep kmem_cache_free trace| grep $target_func | wc -l`
+misscnt=`grep kmem_cache_free trace| grep -v $target_func | wc -l`
if [ $hitcnt -eq 0 ]; then
exit_fail
