4.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Sandeen <sandeen@xxxxxxxxxxx> commit 757a69ef6cf2bf839bd4088e5609ddddd663b0c4 upstream. There are dueling comments in the xfs code about intent for log writes when unmounting a readonly filesystem. In xfs_mountfs, we see the intent: /* * Now the log is fully replayed, we can transition to full read-only * mode for read-only mounts. This will sync all the metadata and clean * the log so that the recovery we just performed does not have to be * replayed again on the next mount. */ and it calls xfs_quiesce_attr(), but by the time we get to xfs_log_unmount_write(), it returns early for a RDONLY mount: * Don't write out unmount record on read-only mounts. Because of this, sequential ro mounts of a filesystem with a dirty log will replay the log each time, which seems odd. Fix this by writing an unmount record even for RO mounts, as long as norecovery wasn't specified (don't write a clean log record if a dirty log may still be there!) and the log device is writable. Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx> Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/xfs/xfs_log.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/fs/xfs/xfs_log.c +++ b/fs/xfs/xfs_log.c @@ -812,11 +812,14 @@ xfs_log_unmount_write(xfs_mount_t *mp) int error; /* - * Don't write out unmount record on read-only mounts. + * Don't write out unmount record on norecovery mounts or ro devices. * Or, if we are doing a forced umount (typically because of IO errors). */ - if (mp->m_flags & XFS_MOUNT_RDONLY) + if (mp->m_flags & XFS_MOUNT_NORECOVERY || + xfs_readonly_buftarg(log->l_mp->m_logdev_targp)) { + ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); return 0; + } error = _xfs_log_force(mp, XFS_LOG_SYNC, NULL); ASSERT(error || !(XLOG_FORCED_SHUTDOWN(log)));