diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index 8fe9df5eba..fe63cff1ca 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -967,8 +967,10 @@ static void *threaded_second_pass(void *data)
 	set_thread_data(data);
 	for (;;) {
 		int i;
-		work_lock();
+		counter_lock();
 		display_progress(progress, nr_resolved_deltas);
+		counter_unlock();
+		work_lock();
 		while (nr_dispatched < nr_objects &&
 		       is_delta_type(objects[nr_dispatched].type))
 			nr_dispatched++;