From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Tue, 02 Oct 2007 02:36:41 -0700 (PDT) Received: from larry.melbourne.sgi.com (larry.melbourne.sgi.com [134.14.52.130]) by oss.sgi.com (8.12.11.20060308/8.12.10/SuSE Linux 0.7) with SMTP id l929aXwG029146 for ; Tue, 2 Oct 2007 02:36:36 -0700 Date: Tue, 2 Oct 2007 19:36:29 +1000 From: David Chinner Subject: Re: [GIT PULL] XFS update for 2.6.23 - revert a commit Message-ID: <20071002093629.GG995458@sgi.com> References: <20071001072350.DF61C58C4C0A@chook.melbourne.sgi.com> <4700EE2A.1020304@sandeen.net> <4701A1D0.5010709@sgi.com> <4701ED51.8050706@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4701ED51.8050706@sgi.com> Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: Lachlan McIlroy Cc: Timothy Shimmin , Eric Sandeen , xfs@oss.sgi.com On Tue, Oct 02, 2007 at 05:03:45PM +1000, Lachlan McIlroy wrote: > Yeah that about sums it up. In an attempt to prevent log replay of inodes > in cases when we shouldn't replay we also prevented log replay of inodes in > cases when we should replay. We end up with directories that refer to > inodes > that were not replayed and we read existing data off disk. That existing > data is usually previous instances of inodes. We had cases of regular files > turning into directories and inode version mismatches. The issue that started tripping this was stale inodes from a previous filesystem being detected as valid clusters of inodes. Hence inodes magically changed from what they were supposed to be and that caused all sorts of problems. FWIW, in a past life XFS was supposed to store the uuid of the filesystem in it's inodes to prevent exactly this sort of confusion, but that was considered expendable and disappeared in version 2 inodes when XFS grew 32bit link counts and project ID's. The padding is still there waiting to be used. Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group