[PATCH RT] posix-timers: Unlock expiry lock in the early return

From: Sebastian Andrzej Siewior
Date: Mon Sep 23 2019 - 12:01:45 EST


Patch ("posix-timers: Add expiry lock") acquired a lock in
run_posix_cpu_timers() but didn't drop the lock in the early return.

Unlock the lock in the early return path.

Reported-by: kbuild test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
kernel/time/posix-cpu-timers.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 20cd92a8b9785..a045813c37021 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1167,8 +1167,10 @@ static void __run_posix_cpu_timers(struct task_struct *tsk)
expiry_lock = this_cpu_ptr(&cpu_timer_expiry_lock);
spin_lock(expiry_lock);

- if (!lock_task_sighand(tsk, &flags))
+ if (!lock_task_sighand(tsk, &flags)) {
+ spin_unlock(expiry_lock);
return;
+ }
/*
* Here we take off tsk->signal->cpu_timers[N] and
* tsk->cpu_timers[N] all the timers that are firing, and
--
2.23.0