Commit 69d54b91 authored Feb 13, 2015 by Wang Nan Committed by Linus Torvalds Feb 13, 2015

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>

parent 977ad481

kernel/kprobes.c

+9 −2

Original line number	Diff line number	Diff line
		@@ -869,7 +869,8 @@ static void __disarm_kprobe(struct kprobe *p, bool reopt)
		{
		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);
		@@ -1571,6 +1572,12 @@ static struct kprobe __disable_kprobe(struct kprobe p)

		/* Try to disarm and disable this/parent probe */
		if (p == orig_p \|\| aggr_kprobe_disabled(orig_p)) {
		/*
		* 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;
		}

Admin message