From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757217AbZCRCbU (ORCPT ); Tue, 17 Mar 2009 22:31:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753241AbZCRCbM (ORCPT ); Tue, 17 Mar 2009 22:31:12 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:63770 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751567AbZCRCbL (ORCPT ); Tue, 17 Mar 2009 22:31:11 -0400 Message-ID: <49C05C94.7030104@cn.fujitsu.com> Date: Wed, 18 Mar 2009 10:29:40 +0800 From: Lai Jiangshan User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) MIME-Version: 1.0 To: Valdis.Kletnieks@vt.edu CC: Andrew Morton , jkosina@suse.cz, gregkh@suse.de, linux-kernel@vger.kernel.org, Oleg Nesterov , Oliver Neukum Subject: Re: 29-rc-mmotm - HID/USB wedge w/ WARNING: at kernel/workqueue.c:371 References: <6648.1237271589@turing-police.cc.vt.edu> <20090317135424.9151c4f8.akpm@linux-foundation.org> <37742.1237327272@turing-police.cc.vt.edu> In-Reply-To: <37742.1237327272@turing-police.cc.vt.edu> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Valdis.Kletnieks@vt.edu wrote: > On Tue, 17 Mar 2009 13:54:24 PDT, Andrew Morton said: > >> It's an error in workqueue-avoid-recursion-in-run_workqueue.patch, methinks. > > Thanks for the diagnosis - I got as far as realizing that any backtrace that > included flush_cpu_workqueue() and worker_thread() had a problem and got > stuck there. > It's dangerous when we allow recursion in run_workqueue(). If it's hard for you avoid flush_scheduled_work() in keventd's work fuction by other fix, you can create another workqueue to handle your works, IMO. Thanks Lai jiangshan