From 53da28755db7fc25ef7b25282e4309f85984e886 Mon Sep 17 00:00:00 2001
Message-Id: <53da28755db7fc25ef7b25282e4309f85984e886.1592846147.git.zanussi@kernel.org>
In-Reply-To: <07cd0dbc80b976663c80755496a03f288decfe5a.1592846146.git.zanussi@kernel.org>
References: <07cd0dbc80b976663c80755496a03f288decfe5a.1592846146.git.zanussi@kernel.org>
From: Julien Grall <julien.grall@arm.com>
Date: Wed, 21 Aug 2019 10:24:08 +0100
Subject: [PATCH 295/330] hrtimer: Don't grab the expiry lock for non-soft
 hrtimer
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.127-rt55.tar.xz

[ Upstream commit fd420354bea2f57c11f3de191dffdeea76531e76 ]

Acquiring the lock in hrtimer_grab_expiry_lock() is designed for
sleeping-locks and should not be used with disabled interrupts.
hrtimer_cancel() may invoke hrtimer_grab_expiry_lock() also for locks
which expire in hard-IRQ context.

Let hrtimer_cancel() invoke hrtimer_grab_expiry_lock() only for locks
which expire in softirq context.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
[bigeasy: rewrite changelog]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 kernel/time/hrtimer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index d6026c170c2d..49d20fe8570f 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -943,7 +943,7 @@ void hrtimer_grab_expiry_lock(const struct hrtimer *timer)
 {
 	struct hrtimer_clock_base *base = READ_ONCE(timer->base);
 
-	if (base && base->cpu_base) {
+	if (timer->is_soft && base && base->cpu_base) {
 		spin_lock(&base->cpu_base->softirq_expiry_lock);
 		spin_unlock(&base->cpu_base->softirq_expiry_lock);
 	}
-- 
2.17.1

