From owner-freebsd-current@FreeBSD.ORG Tue Oct 11 06:41:33 2005 Return-Path: X-Original-To: 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 7259916A41F; Tue, 11 Oct 2005 06:41:33 +0000 (GMT) (envelope-from pjd@garage.freebsd.pl) Received: from mail.garage.freebsd.pl (arm132.internetdsl.tpnet.pl [83.17.198.132]) by mx1.FreeBSD.org (Postfix) with ESMTP id C3CE643D49; Tue, 11 Oct 2005 06:41:31 +0000 (GMT) (envelope-from pjd@garage.freebsd.pl) Received: by mail.garage.freebsd.pl (Postfix, from userid 65534) id BF43E50BDE; Tue, 11 Oct 2005 08:41:29 +0200 (CEST) Received: from localhost (dla186.neoplus.adsl.tpnet.pl [83.24.30.186]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.garage.freebsd.pl (Postfix) with ESMTP id 718E4509F1; Tue, 11 Oct 2005 08:41:23 +0200 (CEST) Date: Tue, 11 Oct 2005 08:41:16 +0200 From: Pawel Jakub Dawidek To: Brooks Davis Message-ID: <20051011064014.GA76710@garage.freebsd.pl> References: <20051005024903.GA72743@heff.fud.org.nz> <20051005203639.GA20552@garage.freebsd.pl> <20051005205515.GA30350@odin.ac.hmc.edu> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="CUfgB8w4ZwR/yMy5" Content-Disposition: inline In-Reply-To: <20051005205515.GA30350@odin.ac.hmc.edu> X-PGP-Key-URL: http://people.freebsd.org/~pjd/pjd.asc X-OS: FreeBSD 7.0-CURRENT i386 User-Agent: mutt-ng/devel-r535 (FreeBSD) X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on mail.garage.freebsd.pl X-Spam-Level: X-Spam-Status: No, score=-0.5 required=3.0 tests=BAYES_00,RCVD_IN_NJABL_DUL, RCVD_IN_SORBS_DUL autolearn=no version=3.0.4 Cc: Brooks Davis , FreeBSD Current , Andrew Thompson Subject: Re: panic: ifc_free_unit: bit is already cleared 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, 11 Oct 2005 06:41:33 -0000 --CUfgB8w4ZwR/yMy5 Content-Type: text/plain; charset=iso-8859-2 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Oct 05, 2005 at 01:55:15PM -0700, Brooks Davis wrote: +> On Wed, Oct 05, 2005 at 10:36:39PM +0200, Pawel Jakub Dawidek wrote: +> > On Wed, Oct 05, 2005 at 03:49:03PM +1300, Andrew Thompson wrote: +> > +> Hi, +> > +>=20 +> > +> I have found a repeatable panic with network device cloning, unfort= unatly I am +> > +> unable to dump on this box. This is sparc64 with a 2 day old curren= t. +> >=20 +> > The order is wrong in vlan_modevent(). +> >=20 +> > if_clone_detach() is freeing ifc_units field, so ifc_free_unit() shoul= d not +> > be called after that. +> >=20 +> > This patch should fix the problem: +> >=20 +> > http://people.freebsd.org/~pjd/patches/if_vlan.c.patch +>=20 +> Yes. This does introduce a race in that a new interface could +> be created between the vlan_clone_destroy loop and the call to +> if_clone_detach. It's going to be hard to trigger, but it probably +> should be fixed. Since cloning isn't performance critical, I think +> adding a dead flag to the clone structure and failing all attempts once +> the flag is set. I think it is a low-risk patch and the race isn't really critical. What do you guys think about going with this fix for 6.0? I'm all for better fix (the one thompsa@ is working on) going to HEAD and 6.1, but better fix - higher risk. So what's your opinion? Or maybe we will be able to create low-risk complete fix? --=20 Pawel Jakub Dawidek http://www.wheel.pl pjd@FreeBSD.org http://www.FreeBSD.org FreeBSD committer Am I Evil? Yes, I Am! --CUfgB8w4ZwR/yMy5 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (FreeBSD) iD8DBQFDS16MForvXbEpPzQRAr+zAJ981doxmwrcbTehCgRemxn++v6U2wCbBYHs mewMhQgDm2FMoqCBK+jAvxU= =AED0 -----END PGP SIGNATURE----- --CUfgB8w4ZwR/yMy5--