From owner-cvs-all@FreeBSD.ORG Tue Jan 20 19:21:09 2004 Return-Path: Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1963F16A4CE; Tue, 20 Jan 2004 19:21:09 -0800 (PST) Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id B39D843D39; Tue, 20 Jan 2004 19:21:07 -0800 (PST) (envelope-from robert@fledge.watson.org) Received: from fledge.watson.org (localhost [127.0.0.1]) by fledge.watson.org (8.12.10/8.12.10) with ESMTP id i0L3J8Ud090797; Tue, 20 Jan 2004 22:19:08 -0500 (EST) (envelope-from robert@fledge.watson.org) Received: from localhost (robert@localhost)i0L3J22Y090794; Tue, 20 Jan 2004 22:19:02 -0500 (EST) (envelope-from robert@fledge.watson.org) Date: Tue, 20 Jan 2004 22:19:02 -0500 (EST) From: Robert Watson X-Sender: robert@fledge.watson.org To: Don Lewis In-Reply-To: <200401210307.i0L37s7E060437@gw.catspoiler.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: wpaul@FreeBSD.org cc: src-committers@FreeBSD.org cc: phk@FreeBSD.org cc: bde@zeta.org.au cc: cvs-src@FreeBSD.org cc: cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/alpha/alpha support.s src/sys/i386/i386 swtch.s src/sys/kern kern_shutdown.c src/sys/sys systm.h X-BeenThere: cvs-all@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the entire tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Jan 2004 03:21:09 -0000 On Tue, 20 Jan 2004, Don Lewis wrote: > It would be extremely helpful to preserve the panic message and > (optionally) the backtrace across the reboot. Crash dumps may not > always be possible for any number of reasons (swap smaller than RAM, > /var/crash too small or overflowing with previous crash dumps, crash > dump takes too long ...). This is especially true in cases where the > machine crashes and reboots unattended. Actually, I was having a very similar conversation with Bill Paul this afternoon. We were discussing dropping a copy of the kernel message buffer onto the header of swap space on panic, if possible, and then dropping them in /var/log/crash.log for management by newsyslog. Then the natural response to "My machine spontaneously reboots" becomes "Look for something recent in /var/log/crash.log", as opposed to "You'll need to enable crash dumps, set up a serial console", etc. It's also something we could turn on by default, as opposed to crash dumps, which would otherwise consume of alot of disk space. Robert N M Watson FreeBSD Core Team, TrustedBSD Projects robert@fledge.watson.org Senior Research Scientist, McAfee Research