From owner-freebsd-current Sun Jul 26 15:12:36 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id PAA16965 for freebsd-current-outgoing; Sun, 26 Jul 1998 15:12:36 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from parkplace.cet.co.jp (parkplace.cet.co.jp [202.32.64.1]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id PAA16957 for ; Sun, 26 Jul 1998 15:12:31 -0700 (PDT) (envelope-from michaelh@cet.co.jp) Received: from localhost (michaelh@localhost) by parkplace.cet.co.jp (8.8.8/CET-v2.2) with SMTP id WAA04456; Sun, 26 Jul 1998 22:10:52 GMT Date: Mon, 27 Jul 1998 07:10:52 +0900 (JST) From: Michael Hancock To: Chris Radek cc: freebsd-current@FreeBSD.ORG Subject: Re: ext2fs and sync panic, still In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Have you looked at the ffs version of the source? There aren't too many people working on ext2fs so I would try getting familiar with ffs since it is kept up to date, obviously. Ext2fs is derived from ffs. Regards, Mike Hancock On Sun, 26 Jul 1998, Chris Radek wrote: > > I have run into the problem where mounting an ext2fs r/w panics as > soon as sync is called. r/o has no problems. This is from current > as of a couple days ago. > > This panic is due to a null pointer dereference in ext2_sync > (ext2_vfsops.c:858) caused by a vnode with a NULL v_data. There is a > comment in ext2_vget warning of a blocking MALLOC() that might cause > this, but I don't understand the comment. Can someone explain this > to me? My first thought was that this was an SMP locking problem, > but a uniprocessor kernel gives the same behavior. > > I could of course skip syncing the vnode if its v_data is NULL but it > seems to me like having this bogus vnode in the list signifies a > bigger problem. There is some locking code in ext2_vget but I don't > understand it. Is it possible that a sync can be called between > getnewvnode() and filling in the structure? (Please excuse any > questions that might be stupid... I'm new to this!) > > Does anyone have insight into this problem? Charlie Fluffy > (fluffy@int.tele.dk) reported the same thing on June 28th and it > doesn't look like anybody has made any progress. > > Unfortunately I can't get a memory dump from this machine because I am > running it diskless. (correct me if this is wrong!) I want to > convert it (gently) from Linux and to do this I need to run it diskless > and mount my ext2 filesystems. > > Thanks, > > Chris To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message