From owner-freebsd-stable@FreeBSD.ORG Mon Jun 12 13:16:48 2006 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 A8A4D16A473 for ; Mon, 12 Jun 2006 13:16:48 +0000 (UTC) (envelope-from olli@lurza.secnetix.de) Received: from lurza.secnetix.de (lurza.secnetix.de [83.120.8.8]) by mx1.FreeBSD.org (Postfix) with ESMTP id AE0BB43D46 for ; Mon, 12 Jun 2006 13:16:47 +0000 (GMT) (envelope-from olli@lurza.secnetix.de) Received: from lurza.secnetix.de (yvwfgj@localhost [127.0.0.1]) by lurza.secnetix.de (8.13.4/8.13.4) with ESMTP id k5CDGep9081755 for ; Mon, 12 Jun 2006 15:16:46 +0200 (CEST) (envelope-from oliver.fromme@secnetix.de) Received: (from olli@localhost) by lurza.secnetix.de (8.13.4/8.13.1/Submit) id k5CDGeHn081754; Mon, 12 Jun 2006 15:16:40 +0200 (CEST) (envelope-from olli) Date: Mon, 12 Jun 2006 15:16:40 +0200 (CEST) Message-Id: <200606121316.k5CDGeHn081754@lurza.secnetix.de> From: Oliver Fromme To: freebsd-stable@FreeBSD.ORG In-Reply-To: <20060612123310.GA25618@tigger.digitaltorque.ca> X-Newsgroups: list.freebsd-stable User-Agent: tin/1.8.0-20051224 ("Ronay") (UNIX) (FreeBSD/4.11-STABLE (i386)) MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-2.1.2 (lurza.secnetix.de [127.0.0.1]); Mon, 12 Jun 2006 15:16:46 +0200 (CEST) Cc: Subject: Re: kernel panic(?) trying to copy data off failed drive with dd X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: freebsd-stable@FreeBSD.ORG List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Jun 2006 13:16:48 -0000 Michael P. Soulier wrote: > Oliver Fromme said: > > So, if your panic is caused purely by software error, and > > it's not already known and documented, filing a PR might be > > a good idea. But if faulty hardware is involved, sending > > a PR is probably useless. > > I would think that it would depend on how the hardware is being used. Yes, I agree. > If the > disk with errors happens to hold the swap partition, then it's difficult to > blame the kernel for crashing. If it's simply reading data, I don't think that > a kernel panic is acceptable. "Simply reading data" would be a software error, and in that case a crash or freeze is not acceptable. (Although it may be very difficult to fix, especially without sacrificing performance significantly, e.g. see mount(8).) However, if the _hardware_ is broken, i.e. the disk drive does not respond correctly, for example producing DMA errors, locking up the bus, or whatever, anything could happen. I guess Søren could tell interesting stories about such cases. :-) Best regards Oliver -- Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing Dienstleistungen mit Schwerpunkt FreeBSD: http://www.secnetix.de/bsd Any opinions expressed in this message may be personal to the author and may not necessarily reflect the opinions of secnetix in any way. "... there are two ways of constructing a software design: One way is to make it so simple that there are _obviously_ no deficiencies and the other way is to make it so complicated that there are no _obvious_ deficiencies." -- C.A.R. Hoare, ACM Turing Award Lecture, 1980