From owner-freebsd-hackers Tue Dec 14 7:58:49 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by hub.freebsd.org (Postfix) with ESMTP id D67DC1515A for ; Tue, 14 Dec 1999 07:58:47 -0800 (PST) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.9.3/8.9.3) id JAA33923; Tue, 14 Dec 1999 09:58:32 -0600 (CST) (envelope-from dan) Date: Tue, 14 Dec 1999 09:58:32 -0600 From: Dan Nelson To: Mark Newton Cc: mauzi@poli.hu, freebsd-hackers@FreeBSD.ORG Subject: Re: umount -f causes page fault in kernel? Message-ID: <19991214095832.A33777@dan.emsphone.com> References: <19991214164126.C1587@internode.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: <19991214164126.C1587@internode.com.au>; from "Mark Newton" on Tue Dec 14 16:41:26 GMT 1999 X-OS: FreeBSD 4.0-CURRENT Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In the last episode (Dec 14), Mark Newton said: > On Mon, Dec 13, 1999 at 04:27:48PM +0100, Gergely EGERVARY wrote: > > mount /cdrom > > cd /cdrom > > umount -f /cdrom > > cd .. > > will cause 100% reproduceable kernel panic (page fault) > > "So don't do that then!" > > > I know forced umount is dangerous, but soo ... =P > > It's described as "dangerous" precisely because it causes a kernel > panic. Well, it actually *shouldn't* cause a kernel panic. I know I've forcibly unmounted filesystems with no problems. Gergely: could you rebuild your kernel with debugging, create a kernel crashdump, and post a stack traceback of the panic? Instructions are at http://www.freebsd.org/handbook/kerneldebug.html . -- Dan Nelson dnelson@emsphone.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message