From owner-freebsd-current@FreeBSD.ORG Fri Apr 2 12:09:02 2004 Return-Path: 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 8D1C016A4E4; Fri, 2 Apr 2004 12:09:02 -0800 (PST) Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.86.163]) by mx1.FreeBSD.org (Postfix) with ESMTP id ED6B243D3F; Fri, 2 Apr 2004 12:09:01 -0800 (PST) (envelope-from phk@phk.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.12.11/8.12.11) with ESMTP id i32K8oC3036770; Fri, 2 Apr 2004 22:08:50 +0200 (CEST) (envelope-from phk@phk.freebsd.dk) To: Vinod Kashyap From: "Poul-Henning Kamp" In-Reply-To: Your message of "Fri, 02 Apr 2004 11:10:46 -0800." Date: Fri, 02 Apr 2004 22:08:49 +0200 Message-ID: <36769.1080936529@critter.freebsd.dk> cc: freebsd-bugs@freebsd.org cc: 'Artem Koutchine' cc: freebsd-current@freebsd.org Subject: Re: there is a bug in twe driver or disk subsystem for sure X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Apr 2004 20:09:02 -0000 In message , Vinod Ka shyap writes: > >The 3ware (twe) driver is obviously not causing this panic. >It's something else (at line 128 in file /usr/src/sys/udm_dbg.c). >Memory modified after free 0x788f400(508) val=20202020 @ 0xe788f400 >panic: Most recently used by devbuf >at line 128 in file /usr/src/sys/udm_dbg.c You're wrong vinod, the bug _is_ most likely in the 3ware driver. What happens is that some piece of RAM is passed to free(9) and some code subsequently writes to it. We only discover this when we try to reuse it next time and it doesn't contain the correct "magic debug pattern". Please compile your kernel with DIAGNOSTICS to enable the extended malloc(9) debugging functions. -- 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.