From owner-freebsd-hackers Sun May 26 5:48:29 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from host217-39-131-156.in-addr.btopenworld.com (host217-39-131-156.in-addr.btopenworld.com [217.39.131.156]) by hub.freebsd.org (Postfix) with ESMTP id 047F137B401 for ; Sun, 26 May 2002 05:48:26 -0700 (PDT) Received: by host217-39-131-156.in-addr.btopenworld.com (Postfix, from userid 1001) id 306DF7D3; Sun, 26 May 2002 13:48:13 +0100 (BST) Date: Sun, 26 May 2002 13:48:12 +0100 From: Dominic Marks To: Ceri Davies Cc: hackers@FreeBSD.org Subject: Re: Another panic in -STABLE, yesterday's tree Message-ID: <20020526134812.A64544@host217-39-131-156.in-addr.btop> References: <20020526112641.GA396@submonkey.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20020526112641.GA396@submonkey.net>; from setantae@submonkey.net on Sun, May 26, 2002 at 12:26:41PM +0100 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Sun, May 26, 2002 at 12:26:41PM +0100, Ceri Davies wrote: > > I've had another kernel panic, this time from a cold boot (the machine had > been powered off overnight), with a new world and kernel built yesterday: > > FreeBSD rhadamanth.private.submonkey.net 4.6-PRERELEASE FreeBSD 4.6-PRERELEASE #0: Wed May 1 21:59:38 BST 2002 setantae@rhadamanth.private.submonkey.net:/usr/obj/usr/src/sys/RHADAMANTH i386 > > I've attached a backtrace - further information is available if someone > tells how to summon it from gdb (I won't delete vmcore this time...) I had this problem. To get good backtraces I do the following. I don't know how "good" this method is, but it works for me. After making your system with makeoptions="-g", add the following to /etc/rc.conf: savecore_flags="-N /usr/obj/usr/src/sys/GALLIUM/kernel.debug" Using the correct path for your kernel name. Then, in your crash dump directory (mine is /usr/crash) run gdb -k kernel.N vmcore.N and you should be able to get a good backtrace with symbols. I find doing it in other ways gets my the same kvm_read message as you have, which is no good. Someone (me) should update the part of the developers handbook because I found following its advice would not get my useful information. Thanks! -- Dominic To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message