Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161205Ab3DECAD (ORCPT ); Thu, 4 Apr 2013 22:00:03 -0400 Received: from mail.active-venture.com ([67.228.131.205]:51420 "EHLO mail.active-venture.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161192Ab3DECAB (ORCPT ); Thu, 4 Apr 2013 22:00:01 -0400 X-Originating-IP: 108.223.40.66 Date: Thu, 4 Apr 2013 18:59:59 -0700 From: Guenter Roeck To: Arkadiusz Miskiewicz Cc: Wim Van Sebroeck , linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: 3.8.3 and 3.9git occasional watchdog oops Message-ID: <20130405015959.GA2566@roeck-us.net> References: <201303142154.20501.arekm@maven.pl> <201304050023.31143.a.miskiewicz@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <201304050023.31143.a.miskiewicz@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1345 Lines: 35 On Fri, Apr 05, 2013 at 12:23:30AM +0200, Arkadiusz Miskiewicz wrote: > On Thursday 14 of March 2013, Arkadiusz Miśkiewicz wrote: > > Hi. > > > > Just hit watchdog related oops in 3.8.3 kernel. Unfortunately photos only. > > > > http://ixion.pld-linux.org/~arekm/watchdog-oops-3.8.3/IMG_8942.JPG > > http://ixion.pld-linux.org/~arekm/watchdog-oops-3.8.3/IMG_8941.JPG > > 3.9git from today isn't any better unfortunately: > > http://ixion.pld-linux.org/~arekm/watchdog-oops-3.9git.jpg > > > > > oops started after I enabled systemd watchdog functionality. Cannot > > reproduce easily. > > > > watchdog here (thinkpad t400) is: > > iTCO_wdt: Found a ICH9M-E TCO device (Version=2, TCOBASE=0x1060) > > Wonder if there is a race condition in the watchdog driver: The watchdog device is opened before watchdog_register_device returns. I suspect systemd waits for a udev event, or by some other means detects that /dev/watchdog was created, and opens it immediately. I just have no idea where exactly the race condition, if there is one, is hiding. Or maybe I am completely off track. Guenter -- 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/