From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:50056 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730223AbeKLFsO (ORCPT ); Mon, 12 Nov 2018 00:48:14 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, peterz@infradead.org, "Frederic Weisbecker" , "Paul E. McKenney" , bigeasy@linutronix.de, "Anna-Maria Gleixner" , "Thomas Gleixner" , "Daniel Bristot de Oliveira" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: Subject: [PATCH 3.16 307/366] nohz: Fix local_timer_softirq_pending() In-Reply-To: Sender: stable-owner@vger.kernel.org List-ID: 3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Anna-Maria Gleixner commit 80d20d35af1edd632a5e7a3b9c0ab7ceff92769e upstream. local_timer_softirq_pending() checks whether the timer softirq is pending with: local_softirq_pending() & TIMER_SOFTIRQ. This is wrong because TIMER_SOFTIRQ is the softirq number and not a bitmask. So the test checks for the wrong bit. Use BIT(TIMER_SOFTIRQ) instead. Fixes: 5d62c183f9e9 ("nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()") Signed-off-by: Anna-Maria Gleixner Signed-off-by: Thomas Gleixner Reviewed-by: Paul E. McKenney Reviewed-by: Daniel Bristot de Oliveira Acked-by: Frederic Weisbecker Cc: bigeasy@linutronix.de Cc: peterz@infradead.org Link: https://lkml.kernel.org/r/20180731161358.29472-1-anna-maria@linutronix.de Signed-off-by: Ben Hutchings --- kernel/time/tick-sched.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -529,7 +529,7 @@ EXPORT_SYMBOL_GPL(get_cpu_iowait_time_us static inline bool local_timer_softirq_pending(void) { - return local_softirq_pending() & TIMER_SOFTIRQ; + return local_softirq_pending() & BIT(TIMER_SOFTIRQ); } static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,