Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758623AbZKKUcJ (ORCPT ); Wed, 11 Nov 2009 15:32:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757181AbZKKUcH (ORCPT ); Wed, 11 Nov 2009 15:32:07 -0500 Received: from mx1.redhat.com ([209.132.183.28]:2203 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755290AbZKKUcF (ORCPT ); Wed, 11 Nov 2009 15:32:05 -0500 Date: Wed, 11 Nov 2009 21:24:33 +0100 From: Oleg Nesterov To: "Rafael J. Wysocki" Cc: Linus Torvalds , Thomas Gleixner , Mike Galbraith , Ingo Molnar , LKML , pm list , Greg KH , Jesse Barnes , Tejun Heo , Marcel Holtmann , linux-bluetooth@vger.kernel.org, Oliver Neukum Subject: Re: GPF in run_workqueue()/list_del_init(cwq->worklist.next) on resume (was: Re: Help needed: Resume problems in 2.6.32-rc, perhaps related to preempt_count leakage in keventd) Message-ID: <20091111202433.GA5714@redhat.com> References: <200911091250.31626.rjw@sisk.pl> <20091111161348.GA27394@redhat.com> <200911112100.16561.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200911112100.16561.rjw@sisk.pl> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1471 Lines: 39 On 11/11, Rafael J. Wysocki wrote: > > On Wednesday 11 November 2009, Oleg Nesterov wrote: > > > > Rafael, could you reproduce the problem with the debugging patch below? > > It tries to detect the case when the pending work was corrupted and > > prints its work->func (saved in the previous item). It should work > > if the work_struct was freed and poisoned, or if it was re-initialized. > > See ck_work(). > > I applied the patch and this is the result of 'dmesg | grep ERR' after 10-or-so > consecutive suspend-resume and hibernate-resume cycles: > > [ 129.008689] ERR!! btusb_waker+0x0/0x27 [btusb] > [ 166.477373] ERR!! btusb_waker+0x0/0x27 [btusb] > [ 203.983665] ERR!! btusb_waker+0x0/0x27 [btusb] > [ 241.636547] ERR!! btusb_waker+0x0/0x27 [btusb] > > which kind of confirms my previous observation that the problem was not > reproducible without Bluetooth. Great, thanks. > So, it looks like the bug is in btusb_destruct(), which should call > cancel_work_sync() on data->waker before freeing 'data'. I guess it should > do the same for data->work. Or. btusb_suspend() and btusb_close() do cancel_work_sync(data->work), perhaps they should cancel data->waker as well, I dunno. I added Oliver to cc. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/