From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756029AbdDRIMX (ORCPT ); Tue, 18 Apr 2017 04:12:23 -0400 Received: from mail-pf0-f194.google.com ([209.85.192.194]:35655 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755700AbdDRIMT (ORCPT ); Tue, 18 Apr 2017 04:12:19 -0400 Date: Tue, 18 Apr 2017 17:12:13 +0900 From: Tejun Heo To: Steven Rostedt Cc: LKML Subject: Re: [WARNING] kernel/workqueue.c:2041 process_one_work (when cpu goes offline) Message-ID: <20170418081213.GF3899@wtj.duckdns.org> References: <20170405151628.33df783f@gandalf.local.home> <20170411000837.GA29406@wtj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170411000837.GA29406@wtj.duckdns.org> User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Tue, Apr 11, 2017 at 09:08:37AM +0900, Tejun Heo wrote: > On Wed, Apr 05, 2017 at 03:16:28PM -0400, Steven Rostedt wrote: > > My tests have started to recently trigger this warning quite often, > > which causes my tests to fail. The test that triggers this is running > > the mmiotracer which forces all but one CPU offline. So, the rescuer handling seems fine and nothing really changed from workqueue side. Any chance cpuset is involved? If so, there was a recent race condition fix 77f88796cee8 ("cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups"). If that's not it, it'd be great if you can explain the test case so that I can repro the problem. Thanks. -- tejun