From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754650AbdCFVIA (ORCPT ); Mon, 6 Mar 2017 16:08:00 -0500 Received: from mail-yw0-f194.google.com ([209.85.161.194]:36667 "EHLO mail-yw0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754464AbdCFVHi (ORCPT ); Mon, 6 Mar 2017 16:07:38 -0500 Date: Mon, 6 Mar 2017 15:39:01 -0500 From: Tejun Heo To: Dave Jones Cc: Linux Kernel Subject: Re: __queue_work oops. Message-ID: <20170306203901.GC26127@htj.duckdns.org> References: <20170227171439.jshx3qplflyrgcv7@codemonkey.org.uk> <20170227183925.GA8707@htj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170227183925.GA8707@htj.duckdns.org> User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Applied the following to wq/for-4.11-fixes. Thanks. ------ 8< ------ >>From 637fdbae60d6cb9f6e963c1079d7e0445c86ff7d Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 6 Mar 2017 15:33:42 -0500 Subject: [PATCH] workqueue: trigger WARN if queue_delayed_work() is called with NULL @wq If queue_delayed_work() gets called with NULL @wq, the kernel will oops asynchronuosly on timer expiration which isn't too helpful in tracking down the offender. This actually happened with smc. __queue_delayed_work() already does several input sanity checks synchronously. Add NULL @wq check. Reported-by: Dave Jones Link: http://lkml.kernel.org/r/20170227171439.jshx3qplflyrgcv7@codemonkey.org.uk Signed-off-by: Tejun Heo --- kernel/workqueue.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 072cbc9..c0168b7 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1507,6 +1507,7 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq, struct timer_list *timer = &dwork->timer; struct work_struct *work = &dwork->work; + WARN_ON_ONCE(!wq); WARN_ON_ONCE(timer->function != delayed_work_timer_fn || timer->data != (unsigned long)dwork); WARN_ON_ONCE(timer_pending(timer)); -- 2.9.3