From owner-freebsd-stable@FreeBSD.ORG Mon Dec 5 12:44:59 2005 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6C6F716A41F for ; Mon, 5 Dec 2005 12:44:59 +0000 (GMT) (envelope-from gavin.atkinson@ury.york.ac.uk) Received: from mail-gw1.york.ac.uk (mail-gw1.york.ac.uk [144.32.128.246]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5CA7943D49 for ; Mon, 5 Dec 2005 12:44:57 +0000 (GMT) (envelope-from gavin.atkinson@ury.york.ac.uk) Received: from buffy.york.ac.uk (buffy-128.york.ac.uk [144.32.128.160]) by mail-gw1.york.ac.uk (8.12.10/8.12.10) with ESMTP id jB5CirXW026037; Mon, 5 Dec 2005 12:44:54 GMT Received: from buffy.york.ac.uk (localhost [127.0.0.1]) by buffy.york.ac.uk (8.13.4/8.13.4) with ESMTP id jB5CirLA070989; Mon, 5 Dec 2005 12:44:53 GMT (envelope-from gavin.atkinson@ury.york.ac.uk) Received: (from ga9@localhost) by buffy.york.ac.uk (8.13.4/8.13.4/Submit) id jB5CiruP070988; Mon, 5 Dec 2005 12:44:53 GMT (envelope-from gavin.atkinson@ury.york.ac.uk) X-Authentication-Warning: buffy.york.ac.uk: ga9 set sender to gavin.atkinson@ury.york.ac.uk using -f From: Gavin Atkinson To: "Bjoern A. Zeeb" In-Reply-To: <20051205113818.I88299@maildrop.int.zabbadoz.net> References: <20051205113818.I88299@maildrop.int.zabbadoz.net> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Mon, 05 Dec 2005 12:44:53 +0000 Message-Id: <1133786693.70431.9.camel@buffy.york.ac.uk> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 FreeBSD GNOME Team Port X-York-MailScanner: Found to be clean X-York-MailScanner-From: gavin.atkinson@ury.york.ac.uk Cc: freebsd-stable@freebsd.org Subject: Re: panic logging out on serial console X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 05 Dec 2005 12:44:59 -0000 On Mon, 2005-12-05 at 11:47 +0000, Bjoern A. Zeeb wrote: > I had been logged in on serial console and typed 'exit' and the > RELENG_6 machine went *kaboom*. I hadn't seen sth like this befire on > any of my other machines: > > i386/RELENG_6 from around 2005-11-17 11:00 UTC. > > --- 8< 8< 8< --- > foo# exit > logout > > Fatal trap 12: page fault while in kernel mode > fault virtual address = 0x0 > fault code = supervisor read, page not present > instruction pointer = 0x20:0x0 > stack pointer = 0x28:0xef699954 > frame pointer = 0x28:0xef699968 > code segment = base 0x0, limit 0xfffff, type 0x1b > = DPL 0, pres 1, def32 1, gran 1 > processor eflags = interrupt enabled, resume, IOPL = 0 > current process = 70703 (getty) > trap number = 12 > panic: page fault > > I have the core file and can save it for some days but it won't > help a lot unless someone tells me how I can skip the frame with > the null pointer in kgdb. I've never had a problem with backtraces (even when IP=0x0) but don't forget you can always look at the stack with (gdb) x/40xw 0xef699954 And then look for addresses that may be within the kernel (probably start with 0xc) I'd be interested to know if there is a possibilituy that your panic may have anything to do with one that I saw http://lists.freebsd.org/pipermail/freebsd-current/2004-December/043944.html which seems to be a race in the tty closedown code (which I guess may also be executed during a logout) Gavin