From: Josef Bacik josef@toxicpanda.com
commit d3beaa253fd6fa40b8b18a216398e6e5376a9d21 upstream.
These are special extent buffers that get rewound in order to lookup the state of the tree at a specific point in time. As such they do not go through the normal initialization paths that set their lockdep class, so handle them appropriately when they are created and before they are locked.
CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana fdmanana@suse.com Signed-off-by: Josef Bacik josef@toxicpanda.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/ctree.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1339,6 +1339,8 @@ tree_mod_log_rewind(struct btrfs_fs_info btrfs_tree_read_unlock_blocking(eb); free_extent_buffer(eb);
+ btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb_rewin), + eb_rewin, btrfs_header_level(eb_rewin)); btrfs_tree_read_lock(eb_rewin); __tree_mod_log_rewind(fs_info, eb_rewin, time_seq, tm); WARN_ON(btrfs_header_nritems(eb_rewin) > @@ -1412,7 +1414,6 @@ get_old_root(struct btrfs_root *root, u6
if (!eb) return NULL; - btrfs_tree_read_lock(eb); if (old_root) { btrfs_set_header_bytenr(eb, eb->start); btrfs_set_header_backref_rev(eb, BTRFS_MIXED_BACKREF_REV); @@ -1420,6 +1421,9 @@ get_old_root(struct btrfs_root *root, u6 btrfs_set_header_level(eb, old_root->level); btrfs_set_header_generation(eb, old_generation); } + btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb), eb, + btrfs_header_level(eb)); + btrfs_tree_read_lock(eb); if (tm) __tree_mod_log_rewind(fs_info, eb, time_seq, tm); else