Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756151AbYCHHJa (ORCPT ); Sat, 8 Mar 2008 02:09:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752688AbYCHHJV (ORCPT ); Sat, 8 Mar 2008 02:09:21 -0500 Received: from tuxrocks.com ([208.78.103.217]:55272 "EHLO tuxrocks.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752676AbYCHHJU (ORCPT ); Sat, 8 Mar 2008 02:09:20 -0500 Message-ID: <47D23B7E.3020505@tuxrocks.com> Date: Sat, 08 Mar 2008 01:08:46 -0600 From: Frank Sorenson User-Agent: Thunderbird 2.0.0.12 (X11/20080226) MIME-Version: 1.0 To: Ingo Molnar , kay.sievers@vrfy.org, Matt_Domsch@dell.com CC: LKML , linux-mm@kvack.org, "Rafael J. Wysocki" Subject: Re: 2.6.25-rc4 OOMs itself dead on bootup References: <47D02940.1030707@tuxrocks.com> <20080306184954.GA15492@elte.hu> <47D1971A.7070500@tuxrocks.com> In-Reply-To: <47D1971A.7070500@tuxrocks.com> X-Enigmail-Version: 0.95.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3247 Lines: 79 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Frank Sorenson wrote: > I did some additional debugging, and I believe you're correct about it > being specific to my system. The system seems to run fine until some > time during the boot. I booted with "init=/bin/sh" (that's how the > system stayed up for 9 minutes), then it died when I tried starting > things up. I've further narrowed the OOM down to udev (though it's not > entirely udev's fault, since 2.6.24 runs fine). > > I ran your debug info tool before killing the box by running > /sbin/start_udev. The output of the tool is at > http://tuxrocks.com/tmp/cfs-debug-info-2008.03.06-14.11.24 > > Something is apparently happening between 2.6.24 and 2.6.25-rc[34] which > causes udev (or something it calls) to behave very badly. Found it. The culprit is 8f47f0b688bba7642dac4e979896e4692177670b dcdbas: add DMI-based module autloading DMI autoload dcdbas on all Dell systems. This looks for BIOS Vendor or System Vendor == Dell, so this should work for systems both Dell-branded and those Dell builds but brands for others. It causes udev to load the dcdbas module at startup, which is used by tools called by HAL for wireless control and backlight control, among other uses. What actually happens is that when udev loads the dcdbas module at startup, modprobe apparently calls "modprobe dcdbas" itself, repeating until the system runs out of resources (in this case, it OOMs). # ps axf ... 506 ? S 0:00 /bin/bash /sbin/start_udev 590 ? S 0:00 \_ /sbin/udevsettle 533 ? S