From 5f0c584daf7464f04114c65dd07269ee2bfedc13 Mon Sep 17 00:00:00 2001 From: Ze Gao Date: Mon, 3 Jul 2023 17:23:36 +0800 Subject: [PATCH] fprobe: add unlock to match a succeeded ftrace_test_recursion_trylock Unlock ftrace recursion lock when fprobe_kprobe_handler() is failed because of some running kprobe. Link: https://lore.kernel.org/all/20230703092336.268371-1-zegao@tencent.com/ Fixes: 3cc4e2c5fbae ("fprobe: make fprobe_kprobe_handler recursion free") Reported-by: Yafang Closes: https://lore.kernel.org/linux-trace-kernel/CALOAHbC6UpfFOOibdDiC7xFc5YFUgZnk3MZ=3Ny6we=AcrNbew@mail.gmail.com/ Signed-off-by: Ze Gao Acked-by: Masami Hiramatsu (Google) Acked-by: Yafang Shao Reviewed-by: Steven Rostedt (Google) Signed-off-by: Masami Hiramatsu (Google) --- kernel/trace/fprobe.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 0121e8c..58e4b36 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -102,12 +102,14 @@ static void fprobe_kprobe_handler(unsigned long ip, unsigned long parent_ip, if (unlikely(kprobe_running())) { fp->nmissed++; - return; + goto recursion_unlock; } kprobe_busy_begin(); __fprobe_handler(ip, parent_ip, ops, fregs); kprobe_busy_end(); + +recursion_unlock: ftrace_test_recursion_unlock(bit); } -- 2.7.4