kprobes: makes kprobes/enabled works correctly for optimized kprobes.
debugfs/kprobes/enabled doesn't work correctly on optimized kprobes.
Masami Hiramatsu has a test report on x86_64 platform:
https://lkml.org/lkml/2015/1/19/274
This patch forces it to unoptimize kprobe if kprobes_all_disarmed is set.
It also checks the flag in unregistering path for skipping unneeded
disarming process when kprobes globally disarmed.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index c397900..c90e417 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -869,7 +869,8 @@
{
struct kprobe *_p;
- unoptimize_kprobe(p, false); /* Try to unoptimize */
+ /* Try to unoptimize */
+ unoptimize_kprobe(p, kprobes_all_disarmed);
if (!kprobe_queued(p)) {
arch_disarm_kprobe(p);
@@ -1571,7 +1572,13 @@
/* Try to disarm and disable this/parent probe */
if (p == orig_p || aggr_kprobe_disabled(orig_p)) {
- disarm_kprobe(orig_p, true);
+ /*
+ * If kprobes_all_disarmed is set, orig_p
+ * should have already been disarmed, so
+ * skip unneed disarming process.
+ */
+ if (!kprobes_all_disarmed)
+ disarm_kprobe(orig_p, true);
orig_p->flags |= KPROBE_FLAG_DISABLED;
}
}