diff --git a/extent-tree.c b/extent-tree.c
index dc999327..4e773581 100644
--- a/extent-tree.c
+++ b/extent-tree.c
@@ -1705,7 +1705,11 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
 update_block:
 	ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0,
 				 data);
-	BUG_ON(ret);
+	if (ret) {
+		printk("update block group failed for %Lu %Lu\n",
+		       ins->objectid, ins->offset);
+		BUG();
+	}
 	return 0;
 }