From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 268867F59 for ; Wed, 12 Jun 2013 20:04:45 -0500 (CDT) Date: Wed, 12 Jun 2013 20:04:41 -0500 From: Ben Myers Subject: Re: [PATCH 1/3] xfs: don't shutdown log recovery on validation errors Message-ID: <20130613010441.GX20932@sgi.com> References: <1371003548-4026-1-git-send-email-david@fromorbit.com> <1371003548-4026-2-git-send-email-david@fromorbit.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1371003548-4026-2-git-send-email-david@fromorbit.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: xfs@oss.sgi.com Hey Dave, On Wed, Jun 12, 2013 at 12:19:06PM +1000, Dave Chinner wrote: > From: Dave Chinner > > Unfortunately, we cannot guarantee that items logged multiple times > and replayed by log recovery do not take objects back in time. When > theya re taken back in time, the go into an intermediate state which > is corrupt, and hence verification that occurs on this intermediate > state causes log recovery to abort with a corruption shutdown. > > Instead of causing a shutdown and unmountable filesystem, don't > verify post-recovery items before they are written to disk. This is > less than optimal, but there is no way to detect this issue for > non-CRC filesystems If log recovery successfully completes, this > will be undone and the object will be consistent by subsequent > transactions that are replayed, so in most cases we don't need to > take drastic action. > > For CRC enabled filesystems, leave the verifiers in place - we need > to call them to recalculate the CRCs on the objects anyway. This > recovery problem canbe solved for such filesystems - we have a LSN > stamped in all metadata at writeback time that we can to determine > whether the item should be replayed or not. This is a separate piece > of work, so is not addressed by this patch. Is there a test case for this one? How are you reproducing this? Thanks, Ben _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs