From owner-freebsd-current Wed Nov 20 11:46:42 2002 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DF50E37B401; Wed, 20 Nov 2002 11:46:41 -0800 (PST) Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id 11E8843E3B; Wed, 20 Nov 2002 11:46:41 -0800 (PST) (envelope-from robert@fledge.watson.org) Received: from fledge.watson.org (fledge.pr.watson.org [192.0.2.3]) by fledge.watson.org (8.12.6/8.12.5) with SMTP id gAKJa3BF053789; Wed, 20 Nov 2002 14:36:03 -0500 (EST) (envelope-from robert@fledge.watson.org) Date: Wed, 20 Nov 2002 14:36:03 -0500 (EST) From: Robert Watson X-Sender: robert@fledge.watson.org To: John Baldwin Cc: "Joel M. Baldwin" , current@FreeBSD.org Subject: Re: panic: sleeping thread owns a mutex - with debug traceback In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Wed, 20 Nov 2002, John Baldwin wrote: > Erm. Did you manage to look at dmesg then? If so, you would have seen > warnings from WITNESS earlier about the locks messing up. If you can > reproduce this and are letting it sit unattended, a better plan might be > to turn on witness_ddb (it's a kernel option, loader tunable, and sysctl > (debug.witness_ddb)) and then when the original error occurs it will > drop into the debugger with a very useful error message. You can also > get a useful trace at that point from ddb. Word of warning though: either use a serial console, or don't run X, because you'll want to be able to see the debugger, and you probably won't get much warning when it's about to drop in. Robert N M Watson FreeBSD Core Team, TrustedBSD Projects robert@fledge.watson.org Network Associates Laboratories To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message