From owner-freebsd-current@FreeBSD.ORG Mon Jul 31 20:46:03 2006 Return-Path: X-Original-To: freebsd-current@freebsd.org 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 A92B716A4DA for ; Mon, 31 Jul 2006 20:46:03 +0000 (UTC) (envelope-from csjp@FreeBSD.org) Received: from ems01.seccuris.com (ems01.seccuris.com [204.112.0.35]) by mx1.FreeBSD.org (Postfix) with SMTP id EED5C43D4C for ; Mon, 31 Jul 2006 20:46:02 +0000 (GMT) (envelope-from csjp@FreeBSD.org) Received: (qmail 67809 invoked by uid 86); 31 Jul 2006 21:00:21 -0000 Received: from unknown (HELO ?127.0.0.1?) (204.112.0.40) by ems01.seccuris.com with SMTP; 31 Jul 2006 21:00:21 -0000 Message-ID: <44CE6C0A.50009@FreeBSD.org> Date: Mon, 31 Jul 2006 15:46:02 -0500 From: "Christian S.J. Peron" User-Agent: Thunderbird 1.5.0.5 (Macintosh/20060719) MIME-Version: 1.0 To: Robert Huff References: <20060726063636.GA58151@freefall.freebsd.org> <17610.836.663396.331448@jerusalem.litteratus.org> In-Reply-To: <17610.836.663396.331448@jerusalem.litteratus.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-current@freebsd.org Subject: Re: LOR when booting CURRENT (ip_divert.c, PFil hook read/write mutex) [#181] 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: Mon, 31 Jul 2006 20:46:03 -0000 Robert Huff wrote: > Yar Tikhiy writes: > > >> FWIW, the LOR still is there. I was seeing it yesterday while >> fiddling with the ipfw and natd rc.d scripts. >> >> lock order reversal: >> 1st 0xc1a36090 inp (divinp) @ /usr/src/sys/modules/ipdivert/../../netinet/ip_divert.c:350 >> 2nd 0xc0a51918 PFil hook read/write mutex (PFil hook read/write mutex) @ /usr/src/sys/net/pfil.c:73 >> > > For the record, I'm (still) getting this also. > > > Robert Huff > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org" > > > This appears to be similar to the LOR associated with IPFW and ucred based rules, I think. Although this is a lock order reversal and it probably isn't a false positive, it should be reasonably harmless, because the pfil hook lock is a reader lock, thus different threads can acquire it (at this point) con-currently, presumably preventing a dead lock from actually occurring here. iirc witness it not aware of the reader/writer semantics, so it makes sense that it will be dropping a warning here. But I can look at this in further detail when I get a bit of time. -- Christian S.J. Peron csjp@FreeBSD.ORG FreeBSD Committer FreeBSD Security Team