From: David Sterba dsterba@suse.com
commit 10a3a3edc5b89a8cd095bc63495fb1e0f42047d9 upstream.
A remount to a read-write filesystem is not safe when there's tree-log to be replayed. Files that could be opened until now might be affected by the changes in the tree-log.
A regular mount is needed to replay the log so the filesystem presents the consistent view with the pending changes included.
CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Anand Jain anand.jain@oracle.com Reviewed-by: Johannes Thumshirn johannes.thumshirn@wdc.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/super.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1803,6 +1803,8 @@ static int btrfs_remount(struct super_bl }
if (btrfs_super_log_root(fs_info->super_copy) != 0) { + btrfs_warn(fs_info, + "mount required to replay tree-log, cannot remount read-write"); ret = -EINVAL; goto restore; }