From owner-freebsd-hackers Sun Apr 27 20:45:47 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id UAA18557 for hackers-outgoing; Sun, 27 Apr 1997 20:45:47 -0700 (PDT) Received: from genesis.atrad.adelaide.edu.au (genesis.atrad.adelaide.edu.au [129.127.96.120]) by hub.freebsd.org (8.8.5/8.8.5) with ESMTP id UAA18552 for ; Sun, 27 Apr 1997 20:45:42 -0700 (PDT) Received: (from msmith@localhost) by genesis.atrad.adelaide.edu.au (8.8.5/8.7.3) id NAA14724; Mon, 28 Apr 1997 13:15:35 +0930 (CST) From: Michael Smith Message-Id: <199704280345.NAA14724@genesis.atrad.adelaide.edu.au> Subject: Re: A Desparate Plea for Help... In-Reply-To: <199704280221.LAA13874@genesis.atrad.adelaide.edu.au> from Michael Smith at "Apr 28, 97 11:51:19 am" To: msmith@atrad.adelaide.edu.au (Michael Smith) Date: Mon, 28 Apr 1997 13:15:34 +0930 (CST) Cc: Shimon@i-Connect.Net, freebsd-hackers@freebsd.org X-Mailer: ELM [version 2.4ME+ PL28 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Michael Smith stands accused of saying: > The trap you see above is somewhere near the top of spec_open in > sys/miscfs/specfs.c. Without knowing exactly what the trap was; > specifically the fault address, it's hard to infer more. There are > several pointer references near the top of spec_open that might be > the problem, the most likely IMHO is : > > /* > * Don't allow open if fs is mounted -nodev. > */ > if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV)) > return (ENXIO); > > We have seen problems with vp->v_mount being NULL before; this > appears most often with MFS filesystems. ... and of course that's completely stupid on my part. If vp->v_mount is null that will _not_ result in a null deref. Further study actually indicates that this function is quite paranoid about its input. Can you tell us which compile options you are using with your kernels, so that someone can build this function and work out where 0x6c is? Are you loading/unloading LKM's on these systems? -- ]] Mike Smith, Software Engineer msmith@gsoft.com.au [[ ]] Genesis Software genesis@gsoft.com.au [[ ]] High-speed data acquisition and (GSM mobile) 0411-222-496 [[ ]] realtime instrument control. (ph) +61-8-8267-3493 [[ ]] Unix hardware collector. "Where are your PEZ?" The Tick [[