From 85a7f8fe8d263b8fd22f3328e32d4f852df8cdf4 Mon Sep 17 00:00:00 2001
Message-Id: <85a7f8fe8d263b8fd22f3328e32d4f852df8cdf4.1592846147.git.zanussi@kernel.org>
In-Reply-To: <07cd0dbc80b976663c80755496a03f288decfe5a.1592846146.git.zanussi@kernel.org>
References: <07cd0dbc80b976663c80755496a03f288decfe5a.1592846146.git.zanussi@kernel.org>
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Mon, 16 Sep 2019 12:33:59 +0200
Subject: [PATCH 298/330] posix-timers: Unlock expiry lock in the early return
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.127-rt55.tar.xz

[ Upstream commit 356a2781375ec58521a9bc3f500488745990c242 ]

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@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 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 765e700962ab..c9964dc3276b 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1175,8 +1175,10 @@ 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
-- 
2.17.1

