From owner-freebsd-current Fri Nov 1 7:37:29 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 5086937B401 for ; Fri, 1 Nov 2002 07:37:28 -0800 (PST) Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.86.163]) by mx1.FreeBSD.org (Postfix) with ESMTP id 73E4743E8A for ; Fri, 1 Nov 2002 07:37:27 -0800 (PST) (envelope-from phk@critter.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.12.6/8.12.6) with ESMTP id gA1FbM9d095736 for ; Fri, 1 Nov 2002 16:37:22 +0100 (CET) (envelope-from phk@critter.freebsd.dk) To: current@freebsd.org Subject: Re: cvs commit: src/sys/fs/specfs spec_vnops.c In-Reply-To: Your message of "Fri, 01 Nov 2002 07:32:12 PST." <200211011532.gA1FWCA4017922@repoman.freebsd.org> Date: Fri, 01 Nov 2002 16:37:22 +0100 Message-ID: <95735.1036165042@critter.freebsd.dk> From: Poul-Henning Kamp 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 In message <200211011532.gA1FWCA4017922@repoman.freebsd.org>, Poul-Henning Kamp writes: >phk 2002/11/01 07:32:12 PST > > Modified files: > sys/fs/specfs spec_vnops.c > Log: > Put a KASSERT in specfs::strategy() to check that the incoming buffer > has a valid b_iocmd. Valid is any one of BIO_{READ,WRITE,DELETE}. > > I have seen at least one case where the bio_cmd field was zero once the > request made it into GEOM. Putting the KASSERT here allows us to spot > the culprit in the backtrace. If any of you encounter this panic ("Wrong b_iocmd buf...") please try to capture a traceback and mail it to me. This is likely connected to the problems Kirk are debugging right now and may be responsible for some of the weirder Heisenbugs people have reported. Worst case, (before this commit) it could result in a read request being carried out as a write request by a disk device driver. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message