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@xxxxxxxxxxxxxxx # 4.4+
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
---
fs/btrfs/super.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 580ba7db67e5..a2554c651548 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1834,6 +1834,8 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data)
}
if (btrfs_super_log_root(fs_info->super_copy) != 0) {
+ btrfs_warn(f_info,
+ "mount required to replay tree-log, cannot remount read-write");
ret = -EINVAL;
goto restore;
}
--
2.24.0
