diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index c74c6bd..2caf780 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1102,7 +1102,7 @@ static void wb_update_write_bandwidth(struct bdi_writeback *wb,
 	bw = written - min(written, wb->written_stamp);
 	bw *= HZ;
 	if (unlikely(elapsed > period)) {
-		do_div(bw, elapsed);
+		bw = div64_ul(bw, elapsed);
 		avg = bw;
 		goto out;
 	}