Commit 6e3abef2a27e for kernel
commit 6e3abef2a27e7402a94111c9eff85d887e64a309
Author: Martin Kaiser <martin@kaiser.cx>
Date: Tue Aug 4 21:46:35 2026 +0200
selftests/ftrace: refactor eprobes test to fix argument checks
The add/remove eprobe test installs an eprobe for the openat syscall and
runs ls. It checks the filenames that were opened by ls against a
whitelist and a blacklist.
Commit 206b25c09080 ("tracing: eprobe: read the complete FILTER_PTR_STRING
pointer") fixed access to some string fields in eprobes. This triggers
test failures as the blacklist does not allow relative paths for the
openat parameters.
What makes this test unstable is the fact that the openat calls vary a
lot between different systems.
Refactor the test to make it more robust. "cd <directory>" will issue a
chdir syscall with the target directory as parameter. Set an eprobe on
the sys_enter_chdir event and filter for the exact directory name. Allow
(fault) as fallback.
Link: https://lore.kernel.org/all/20260804194705.760893-1-martin@kaiser.cx/
Fixes: 206b25c09080 ("tracing: eprobe: read the complete FILTER_PTR_STRING pointer")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202607151010.b68428e1-lkp@intel.com
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
index c300eb020262..e2322693d0c3 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
@@ -1,16 +1,16 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
# description: Generic dynamic event - add/remove eprobe events
-# requires: dynamic_events events/syscalls/sys_enter_openat "<attached-group>.<attached-event> [<args>]":README
+# requires: dynamic_events events/syscalls/sys_enter_chdir "<attached-group>.<attached-event> [<args>]":README
echo 0 > events/enable
clear_dynamic_events
SYSTEM="syscalls"
-EVENT="sys_enter_openat"
+EVENT="sys_enter_chdir"
FIELD="filename"
-EPROBE="eprobe_open"
+EPROBE="eprobe_chdir"
OPTIONS="file=+0(\$filename):ustring"
echo "e:$EPROBE $SYSTEM/$EVENT $OPTIONS" >> dynamic_events
@@ -18,20 +18,14 @@ grep -q "$EPROBE" dynamic_events
test -d events/eprobes/$EPROBE
echo 1 > events/eprobes/$EPROBE/enable
-ls
+cd /sys/kernel/tracing
echo 0 > events/eprobes/$EPROBE/enable
-content=`grep '^ *ls-' trace | grep 'file='`
-nocontent=`grep '^ *ls-' trace | grep 'file=' | grep -v -e '"/' -e '"."' -e '(fault)' ` || true
-
+content=`grep -e 'file="/sys/kernel/tracing"\|(fault)' trace`
if [ -z "$content" ]; then
exit_fail
fi
-if [ ! -z "$nocontent" ]; then
- exit_fail
-fi
-
echo "-:$EPROBE" >> dynamic_events
! grep -q "$EPROBE" dynamic_events