From owner-freebsd-hackers@FreeBSD.ORG Fri Dec 29 22:33:07 2006 Return-Path: X-Original-To: FreeBSD-Hackers@FreeBSD.org Delivered-To: FreeBSD-Hackers@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id C9CE016A407 for ; Fri, 29 Dec 2006 22:33:07 +0000 (UTC) (envelope-from jan@digitaldaemon.com) Received: from digitaldaemon.com (digitaldaemon.com [63.105.9.34]) by mx1.freebsd.org (Postfix) with SMTP id 0527113C458 for ; Fri, 29 Dec 2006 22:33:06 +0000 (UTC) (envelope-from jan@digitaldaemon.com) Received: (qmail 79498 invoked by uid 98); 29 Dec 2006 22:33:04 -0000 Received: from 63.105.9.34 by digitaldaemon.com (envelope-from , uid 89) with qmail-scanner-1.25 (clamdscan: 0.87/1195. Clear:RC:1(63.105.9.34):. Processed in 0.243414 secs); 29 Dec 2006 22:33:04 -0000 X-Qmail-Scanner-Mail-From: jan@digitaldaemon.com via digitaldaemon.com X-Qmail-Scanner: 1.25 (Clear:RC:1(63.105.9.34):. Processed in 0.243414 secs) Received: from digitaldaemon.com (HELO ?16.81.102.2?) (63.105.9.34) by digitaldaemon.com with SMTP; 29 Dec 2006 22:33:04 -0000 Message-ID: <4595979B.1030104@digitaldaemon.com> Date: Fri, 29 Dec 2006 17:32:59 -0500 From: Jan Knepper User-Agent: Thunderbird 1.5.0.9 (Windows/20061207) MIME-Version: 1.0 To: Robert Watson References: <45918F6E.90006@digitaldaemon.com> <004c01c7293b$d5e03b40$6500a8c0@laptopt> <4591CB3C.1060902@digitaldaemon.com> <20061227033742.GA9706@xor.obsecurity.org> <4593552E.80400@digitaldaemon.com> <20061229213013.E86685@fledge.watson.org> In-Reply-To: <20061229213013.E86685@fledge.watson.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Tim McCullagh , FreeBSD ISP , Kris Kennaway , FreeBSD Hackers Subject: Re: 6.1-RELEASE / 6.2 Kernel Crash... X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 29 Dec 2006 22:33:07 -0000 Robert Watson wrote: > On Thu, 28 Dec 2006, Jan Knepper wrote: > >>> Sounds like a bug in the support for your ATA hardware, or your >>> hardware is broken. The very least you'll need to do is to obtain a >>> crashdump and debugging backtrace (see the developers handbook) and >>> CC it to sos@ >>> >> This is getting funnier... >> I added: >> dumpdev="AUTO" >> to: rc.conf >> Rebooted the system and tried to get it to crash again... >> And indeed it does in process 9: taskq >> >> Then it starts dumping which takes a couple of seconds as the machine >> has 2 GB Ram... >> >> Than it reboots... and the next thing you know... savecore does NOT >> recognize a dump on the swap file system. If does not save anything >> to /var/crash... Tried this about 10 times... No luck... >> >> Any other idea's? > > Yeah, unfortunately if some combination of storage driver and hardware > aren't working, it's hard to get a dump... No kidding! > The usual fallback here is to use a serial console to capture > debugging information from DDB and to skip the dump side of things. > In fact, I prefer debugging that way most of the time. The reason for > using a serial console (or firewire) is to avoid having to hand-copy > trap and debugging information, which gets very painful very quickly. > Compile DDB and KDB into your kernel, and configure a serial console, > and a panic should lead to the system entering the debugger. The > usual first command to type is "trace" to generate a backtrace; it's > often useful also to do "show pcpu", "show allpcpu", "alltrace", and > "ps", although for the problem you're seeing the last two may be less > useful. > > The 0x50 trap address in your post suggests this is a NULL pointer > dereference. What we now need to do is work out what piece of code is > dereferencing the pointer improperly, which is where the backtrace > comes in. > > If you could copy and paste all that DDB/KDB output into an e-mail > (or, perhaps more ideally, a PR), that would be great. Thanks for the reply Robert. Since this machine runs at my house I hope to get to this over the weekend. I will definitely try to get this information out as soon as I decently can. Thanks! Jan Knepper