Btrfs: printk fixes

Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index 0564a73..13c3028 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -102,7 +102,7 @@
 		ret = btrfs_del_item(trans, root, path);
 	} else {
 		btrfs_set_root_refs(ri, refs - 1);
-printk("ref now %u root %llu %Lu %u\n", refs -1, key->objectid, key->offset, key->flags);
+		WARN_ON(1);
 		mark_buffer_dirty(path->nodes[0]);
 	}
 out: