From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752325AbdLBAEi (ORCPT ); Fri, 1 Dec 2017 19:04:38 -0500 Received: from mail.kernel.org ([198.145.29.99]:44248 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752071AbdLBAE3 (ORCPT ); Fri, 1 Dec 2017 19:04:29 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8AF0A219A5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=rostedt@goodmis.org Message-Id: <20171202000427.582487309@goodmis.org> User-Agent: quilt/0.63-1 Date: Fri, 01 Dec 2017 19:01:55 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-rt-users Cc: Thomas Gleixner , Carsten Emde , Sebastian Andrzej Siewior , John Kacur , Paul Gortmaker , Julia Cartwright , Daniel Wagner , tom.zanussi@linux.intel.com, Alex Shi , stable-rt@vger.kernel.org, Mike Galbraith Subject: [PATCH RT 06/15] kernel/hrtimer: migrate deferred timer on CPU down References: <20171202000149.842718953@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=0006-kernel-hrtimer-migrate-deferred-timer-on-CPU-down.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9.65-rt57-rc2 stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior hrtimers, which were deferred to the softirq context, and expire between softirq shutdown and hrtimer migration are dangling around. If the CPU goes back up the list head will be initialized and this corrupts the timer's list. It will remain unnoticed until a hrtimer_cancel(). This moves those timers so they will expire. Cc: stable-rt@vger.kernel.org Reported-by: Mike Galbraith Tested-by: Mike Galbraith Signed-off-by: Sebastian Andrzej Siewior --- kernel/time/hrtimer.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 0797bd6eadb4..39e4435b8451 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1860,6 +1860,11 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base, */ enqueue_hrtimer(timer, new_base); } +#ifdef CONFIG_PREEMPT_RT_BASE + list_splice_tail(&old_base->expired, &new_base->expired); + if (!list_empty(&new_base->expired)) + raise_softirq_irqoff(HRTIMER_SOFTIRQ); +#endif } int hrtimers_dead_cpu(unsigned int scpu) -- 2.13.2