From owner-freebsd-current@FreeBSD.ORG Sat Feb 16 21:08:46 2008 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E75AA16A41B for ; Sat, 16 Feb 2008 21:08:46 +0000 (UTC) (envelope-from nox@saturn.kn-bremen.de) Received: from gwyn.kn-bremen.de (gwyn.kn-bremen.de [212.63.36.242]) by mx1.freebsd.org (Postfix) with ESMTP id 87B4813C4DB for ; Sat, 16 Feb 2008 21:08:46 +0000 (UTC) (envelope-from nox@saturn.kn-bremen.de) Received: by gwyn.kn-bremen.de (Postfix, from userid 10) id 726CA283490; Sat, 16 Feb 2008 22:08:45 +0100 (CET) Received: from saturn.kn-bremen.de (nox@localhost [127.0.0.1]) by saturn.kn-bremen.de (8.14.2/8.13.8) with ESMTP id m1GL7b9m041121; Sat, 16 Feb 2008 22:07:37 +0100 (CET) (envelope-from nox@saturn.kn-bremen.de) Received: (from nox@localhost) by saturn.kn-bremen.de (8.14.2/8.13.6/Submit) id m1GL7bQm041120; Sat, 16 Feb 2008 22:07:37 +0100 (CET) (envelope-from nox) From: Juergen Lock Date: Sat, 16 Feb 2008 22:07:31 +0100 To: MFL Commissioner Message-ID: <20080216210731.GA40417@saturn.kn-bremen.de> References: <43555.82.234.78.29.1203154742.squirrel@secure.synsport.net> <20080216175811.GA33393@saturn.kn-bremen.de> <47B7352B.1040302@marino.st> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47B7352B.1040302@marino.st> User-Agent: Mutt/1.5.16 (2007-06-09) X-Mailman-Approved-At: Sat, 16 Feb 2008 21:26:57 +0000 Cc: freebsd-current@freebsd.org Subject: Re: 7.0 RC2 kernel panic with Kqemu/AMD64 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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, 16 Feb 2008 21:08:47 -0000 On Sat, Feb 16, 2008 at 08:10:35PM +0100, MFL Commissioner wrote: > Juergen, > I would be happy to help debug this, although someone would have to give me > step by step instructions on what to do exactly. > This is a development machine that (roughly) mirrors a production setup, so > I have maintain the SMP/AMD64 configuration. > What I am still not quite clear on is this: Is this a Qemu problem or > FreeBSD kernel problem? I guess its a kqemu problem that only shows up on FreeBSD, or a combination of issues in kqemu and the FreeBSD kernel, but as I said the actual cause of the problem is still unknown... > > Anyway, I'll do what you ask to provide you with my backtraces, but I doubt > that I will be able to interpret the results. OK, I guess you want to start here: http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/kerneldebug.html and http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/kerneldebug-gdb.html And of course you want to build a debug kernel (makeoptions DEBUG=-g), building a kernel is explained here: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig-building.html I also had to put DDB into the kernel so that it gets built without -fomit-frame-pointer (you probably want KDB_UNATTENDED then too, and KDB_TRACE while you're at it.) Oh and I guess you want to disable minidumps also (sysctl debug.minidump=0), there's a race in there that might(!) cause not so useful dumps otherwise. Then when you have a dump, post a script(1) of a `bt' in kgdb, and we'll see if it tells more than the backtraces I got... Thanx, Juergen