From owner-freebsd-stable@FreeBSD.ORG Wed Dec 7 14:28:48 2005 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9C73F16A449; Wed, 7 Dec 2005 14:28:48 +0000 (GMT) (envelope-from jhb@freebsd.org) Received: from speedfactory.net (mail6.speedfactory.net [66.23.216.219]) by mx1.FreeBSD.org (Postfix) with ESMTP id 505B043D62; Wed, 7 Dec 2005 14:28:39 +0000 (GMT) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (unverified [66.23.211.162]) by speedfactory.net (SurgeMail 3.5b3) with ESMTP id 3319101 for multiple; Wed, 07 Dec 2005 09:29:49 -0500 Received: from zion.baldwin.cx (zion.baldwin.cx [192.168.0.7]) (authenticated bits=0) by server.baldwin.cx (8.13.1/8.13.1) with ESMTP id jB7ERYo5056800; Wed, 7 Dec 2005 09:27:42 -0500 (EST) (envelope-from jhb@freebsd.org) From: John Baldwin To: Yuri Khotyaintsev Date: Wed, 7 Dec 2005 09:27:12 -0500 User-Agent: KMail/1.8.3 References: <200512021100.03167.yuri@irfu.se> <200512020854.20959.jhb@freebsd.org> <200512070847.04980.yuri@irfu.se> In-Reply-To: <200512070847.04980.yuri@irfu.se> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Message-Id: <200512070927.14391.jhb@freebsd.org> X-Spam-Status: No, score=-2.8 required=4.2 tests=ALL_TRUSTED autolearn=failed version=3.0.2 X-Spam-Checker-Version: SpamAssassin 3.0.2 (2004-11-16) on server.baldwin.cx X-Server: High Performance Mail Server - http://surgemail.com r=1653887525 Cc: freebsd-hackers@freebsd.org, freebsd-stable@freebsd.org Subject: Re: Fatal trap 12: page fault while in kernel mode X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 07 Dec 2005 14:28:48 -0000 On Wednesday 07 December 2005 02:47 am, Yuri Khotyaintsev wrote: > On Friday 02 December 2005 14.54, John Baldwin wrote: > > On Friday 02 December 2005 05:00 am, Yuri Khotyaintsev wrote: > > > I have the following panic occurring several times a week. The machine > > > is an NFS server, and it usually panics early in the morning, when > > > first people try to access it. After reboot it may work OK for 1-2 > > > days, and then panics again. I have tried changing memory and replaci= ng > > > disk which was exported via NFS, but nothing helped :( > > > > > > Any suggestion on how to fix this panic will be very much appreciated= ! > > > > This panic (in propagate_priority) is usually caused when a thread goes > > to sleep while holding a mutex (which is forbidden). If you enable > > INVARIANTS and/or WITNESS you should get a better panic, and with WITNE= SS > > you will even be warned when a thread goes to sleep while holding a > > mutex. However, these options do introduce considerable execution > > overhead, and sometimes that overhead changes the timing enough to hide > > the race. :( > > Here are the two panics which I got with INVARIANTS and WITNESS enabled. > > Unread portion of the kernel message buffer: > Memory modified after free 0xc4759e00(508) val=3D0 @ 0xc4759e00 > panic: Most recently used by UFS dirhash Well, this isn't the panic I was expecting, but it points to something=20 trashing free'd memory via a stale pointer or some such. You might be able= =20 to use MEMGUARD to track this down. =2D-=20 John Baldwin =A0<>< =A0http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" =A0=3D =A0http://www.FreeBSD.org