From owner-freebsd-current@FreeBSD.ORG Sat May 3 03:47:24 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5151337B408; Sat, 3 May 2003 03:47:24 -0700 (PDT) Received: from gw.catspoiler.org (217-ip-163.nccn.net [209.79.217.163]) by mx1.FreeBSD.org (Postfix) with ESMTP id 4002E43FBD; Sat, 3 May 2003 03:47:23 -0700 (PDT) (envelope-from truckman@FreeBSD.org) Received: from FreeBSD.org (scratch.catspoiler.org [192.168.101.3]) by gw.catspoiler.org (8.12.9/8.12.9) with ESMTP id h43AlDM7017535; Sat, 3 May 2003 03:47:17 -0700 (PDT) (envelope-from truckman@FreeBSD.org) Message-Id: <200305031047.h43AlDM7017535@gw.catspoiler.org> Date: Sat, 3 May 2003 03:47:13 -0700 (PDT) From: Don Lewis To: rwatson@FreeBSD.org In-Reply-To: MIME-Version: 1.0 Content-Type: TEXT/plain; charset=us-ascii cc: jeff@FreeBSD.org cc: current@FreeBSD.org cc: kirk@mckusick.com Subject: Re: ffs_blkfree: freeing free block -- ps, traces, fsck log X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 03 May 2003 10:47:24 -0000 On 2 May, Robert Watson wrote: > > I updated a pxe box to a recent -current, and applied it to a UFS > partition I had on disk. I ran several parallel tars, an rm -Rf on one of > the tar extract targets, and a dd if=/dev/zero of=tmp on the partition, > and within a few minutes reproduced the nefarious ffs_blkfree() panic. > Some debugging information as follows; I included stack traces of some of > the more interesting threads. I've also included the fsck output below -- > the background file system checker was not active at the time as it's > manually mounted and fscked when used; I believe the file system has never > actually had the background file system checker used on it, certainly not > with a recent kernel. The output from fsck -y on the partition is also > attached. As you can see, there are some alarming "ALLOCATED FRAG xxx > MARKED FREE" messages. Have you tried to see if the DEBUG_VFS_LOCKS kernel configuration option catches any vnode locking problems? I'm using this option and so far I have not been able to trigger the bug. I see that you're running NFS, though it appears to be idle at the time of the crash. I tried the NFS server code for the first time the other day with the DEBUG_VFS_LOCKS option and immediately ran into some locking bugs. The client code is in pretty good shape.