Dave, On Tue, Aug 27, 2013 at 11:39:37AM +1000, Dave Chinner wrote: > From: Dave Chinner <dchinner@xxxxxxxxxx> > > CRC enabled filesystems fail log recovery with 100% reliability on > xfstests xfs/085 with the following failure: Unfortunately I have not been able to hit this one... not sure why. > XFS (vdb): Mounting Filesystem > XFS (vdb): Starting recovery (logdev: internal) > XFS (vdb): Corruption detected. Unmount and run xfs_repair > XFS (vdb): bad inode magic/vsn daddr 144 #0 (magic=0) > XFS: Assertion failed: 0, file: fs/xfs/xfs_inode_buf.c, line: 95 > > The problem is that the inode buffer has not been recovered before > the readahead on the inode buffer is issued. The checkpoint being > recovered actually allocates the inode chunk we are doing readahead > from, so what comes from disk during readahead is essentially > random and the verifier barfs on it. > > This inode buffer readahead problem affects non-crc filesystems, > too, but xfstests does not trigger it at all on such > configurations.... > > Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> I've been mulling this one over for a bit, and I'm not quite sure this is correct: My feeling is that in light of commit 9222a9cf, if we do take part of a buffer back in time, the write verifier should fail. I think for a v2 inode the read and write verifiers should both be disabled for the duration of recovery. For v3 inodes, I suspect the current situation where we do use write verifiers is broken in the same way, at least until we pull in 'xfs: prevent transient corrupt states during log recovery', which, as you say, won't fix the problem for the v2 inode. I'll pull this in and send a patch to that effect. Reviewed-by: Ben Myers <bpm@xxxxxxx> Regards, Ben _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
