From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752253AbaGHOqh (ORCPT ); Tue, 8 Jul 2014 10:46:37 -0400 Received: from mail-qg0-f43.google.com ([209.85.192.43]:36083 "EHLO mail-qg0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750707AbaGHOqf (ORCPT ); Tue, 8 Jul 2014 10:46:35 -0400 Date: Tue, 8 Jul 2014 10:46:32 -0400 From: Tejun Heo To: Fengguang Wu Cc: Jet Chen , Su Tao , Yuanhan Liu , LKP , linux-kernel@vger.kernel.org, Jiri Kosina Subject: Re: [workqueue] WARNING: CPU: 0 PID: 76 at drivers/block/floppy.c:968 schedule_bh() Message-ID: <20140708144632.GF4979@htj.dyndns.org> References: <20140708021149.GA12956@localhost> <20140708140430.GE4979@htj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140708140430.GE4979@htj.dyndns.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 08, 2014 at 10:04:30AM -0400, Tejun Heo wrote: ... > Hmmm... this is schedule_bh() in floppy.c complaining that the work > item is already pending. The cond_resched() addition by b22ce2785d97 > doesn't change the semantics around work item execution although it > could have exposed an existing problem in the floppy driver. I'll > look into how this could happen. It doesn't reproduce here and nothing really stands out to me. It probably involves floppy_work requeueing itself and something else getting executed inbetween which wouldn't have happend before, but I can't figure out what that could be and either can I follow the control flow the driver. :) Jiri, any ideas? Thanks. -- tejun