diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 6b7eee92d981..f1616aa8d0f5 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -334,6 +334,8 @@ out:
 
 void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em)
 {
+	lockdep_assert_held_write(&tree->lock);
+
 	clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
 	if (extent_map_in_tree(em))
 		try_merge_map(tree, em);