From owner-freebsd-current@FreeBSD.ORG Tue Oct 16 02:54:29 2007 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 1F5DC16A417 for ; Tue, 16 Oct 2007 02:54:29 +0000 (UTC) (envelope-from anderson@freebsd.org) Received: from ns.trinitel.com (186.161.36.72.static.reverse.ltdomains.com [72.36.161.186]) by mx1.freebsd.org (Postfix) with ESMTP id E4D4B13C461 for ; Tue, 16 Oct 2007 02:54:28 +0000 (UTC) (envelope-from anderson@freebsd.org) Received: from proton.local (r74-193-81-203.pfvlcmta01.grtntx.tl.dh.suddenlink.net [74.193.81.203]) (authenticated bits=0) by ns.trinitel.com (8.14.1/8.14.1) with ESMTP id l9G2s2Pv042108; Mon, 15 Oct 2007 21:54:04 -0500 (CDT) (envelope-from anderson@freebsd.org) Message-ID: <471427BE.10500@freebsd.org> Date: Mon, 15 Oct 2007 21:53:50 -0500 From: Eric Anderson User-Agent: Thunderbird 2.0.0.6 (Macintosh/20070728) MIME-Version: 1.0 To: Pieter de Goeje References: <1191175387.92510.6.camel@shumai.marcuscom.com> <200710131857.46963.pieter@degoeje.nl> <471170E1.2090205@freebsd.org> <200710140408.46121.pieter@degoeje.nl> In-Reply-To: <200710140408.46121.pieter@degoeje.nl> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-2.0 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=3.1.8 X-Spam-Checker-Version: SpamAssassin 3.1.8 (2007-02-13) on ns.trinitel.com Cc: freebsd-current@freebsd.org, Rolf Witt Subject: Re: panic: ffs_blkfree: freeing free block X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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: Tue, 16 Oct 2007 02:54:29 -0000 Pieter de Goeje wrote: > On Sunday 14 October 2007, Eric Anderson wrote: >> Pieter de Goeje wrote: >>> On Saturday 13 October 2007, Rolf Witt wrote: >>>> Backtrace from crash tonight (after portsnap cron): >>> >>> >>>> # uname -a >>>> FreeBSD peanuts.homenet.local 7.0-PRERELEASE FreeBSD 7.0-PRERELEASE >>>> #121: Thu Oct 11 16:29:05 CEST 2007 >>>> rowi@peanuts.homenet.local:/usr/obj/usr/src/sys/PEANUTS i386 >>>> >>>> Sources from Builddate. >>>> >>>> Rowi >>> Eric sent me this patch: >>> http://www.googlebit.com/freebsd/patches/ffs_softdep.c-patch >>> which seems to be working great so far. I am still testing it, but I >>> think it fixed the problem. >>> To apply, cd /usr/src; patch < /path/to/patch and then rebuild the >>> kernel. >>> >>> Cheers, >>> Pieter de Goeje >> It doesn't actually 'fix' the problem, but I think it helps identify it. >> I'm not 100% certain if this is the right fix our not, but so far >> feedback has been good when running with this patch. >> >> Can somebody confirm that this patch is ok? >> >> Eric > Can you elaborate on what this patch exactly does / what the problem is? > > Pieter I think the problem is that blocks are being put in the worklist twice, but I'm not certain why yet. The patch reduces the chance of this happening by more often removing the block from the worklist instead of leaving it on. I think actually the patch is hiding the real issue more than anything, which is why I said it isn't fixing the problem, but because of the reports I've seen, I think we're sniffing in the right area. I'll be looking more into this soon, when I get another few minutes of free time and my debugger.. Eric