From owner-freebsd-current@FreeBSD.ORG Wed Mar 18 18:08:11 2009 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 DD48B106582B; Wed, 18 Mar 2009 18:08:11 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id A9C748FC16; Wed, 18 Mar 2009 18:08:11 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (pool-98-109-39-197.nwrknj.fios.verizon.net [98.109.39.197]) by cyrus.watson.org (Postfix) with ESMTPSA id 3C03B46B81; Wed, 18 Mar 2009 14:08:11 -0400 (EDT) Received: from localhost (john@localhost [127.0.0.1]) (authenticated bits=0) by server.baldwin.cx (8.14.3/8.14.3) with ESMTP id n2II7TJx007423; Wed, 18 Mar 2009 14:08:05 -0400 (EDT) (envelope-from jhb@freebsd.org) From: John Baldwin To: Pawel Jakub Dawidek Date: Wed, 18 Mar 2009 12:09:18 -0400 User-Agent: KMail/1.9.7 References: <20090312175345.Y80227@rust.salford.ac.uk> <49BAA103.2060508@FreeBSD.org> <20090317070440.GE2012@garage.freebsd.pl> In-Reply-To: <20090317070440.GE2012@garage.freebsd.pl> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200903181209.18970.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-2.0.2 (server.baldwin.cx [127.0.0.1]); Wed, 18 Mar 2009 14:08:05 -0400 (EDT) X-Virus-Scanned: ClamAV 0.94.2/9130/Wed Mar 18 09:51:53 2009 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx Cc: "freebsd-current@freebsd.org" , Attilio Rao , Tim Kientzle , Mark Powell , Anonymous , Peter Schuller Subject: Re: repeatable ZFS panic: share->excl 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: Wed, 18 Mar 2009 18:08:12 -0000 On Tuesday 17 March 2009 3:04:40 am Pawel Jakub Dawidek wrote: > On Fri, Mar 13, 2009 at 02:08:03PM -0400, John Baldwin wrote: > > John Baldwin wrote: > > >Yes, I think that is the real bug. Looking at this further I think > > >zfs_get_xattrdir() will return the vnode locked if it has to create a > > >new node via zfs_make_attrdir() but only returns it held and unlocked if > > >it finds an existing one. So my new patch is to just fix > > >zfs_get_xattrdir() to unlock the vnode if it creates a new one like so: > > > > > >(Sorry, TBird is probably going to butcher all the whitespace): > > > > > >--- > > >//depot/user/jhb/lock/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_dir.c > > >+++ > > >/Users/jhb/work/p4/lock/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_dir.c > > > > > >@@ -940,6 +940,7 @@ > > > /* NB: we already did dmu_tx_wait() if necessary */ > > > goto top; > > > } > > >+ VOP_UNLOCK(*xvpp, 0); > > > > > > return (error); > > > } > > > > > >A non-butchered version is at www.FreeBSD.org/~jhb/patches/zfs_ea.patch. > > > > So lulf@ reports success with this patch. Pawel, can you review it? > > Yes, it works for me too and looks good. The only thing we need to > change is to check for error beeing 0 before unlocking the vnode. > The zfs_make_xattrdir() function can still return with EIO, so I'd add > something like this: > > if (error == 0) > VOP_UNLOCK(*xvpp, 0); Yes, I realized this about 30 minutes after I sent this e-mail. :-P I will commit a version with the error check today. > Thank you John for spending time on tracking this one down. Sure, was good to read a bit of the ZFS code. -- John Baldwin