diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 3a07f6d8bc0b..7cc67e39e7a4 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -649,6 +649,16 @@ static long wb_writeback(struct bdi_writeback *wb,
 		if (work->nr_pages <= 0)
 			break;
 
+		/*
+		 * Background writeout and kupdate-style writeback may
+		 * run forever. Stop them if there is other work to do
+		 * so that e.g. sync can proceed. They'll be restarted
+		 * after the other works are all done.
+		 */
+		if ((work->for_background || work->for_kupdate) &&
+		    !list_empty(&wb->bdi->work_list))
+			break;
+
 		/*
 		 * For background writeout, stop when we are below the
 		 * background dirty threshold