diff --git a/mm/readahead.c b/mm/readahead.c
index e5d0a56218de..4d33be2af009 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -578,7 +578,11 @@ static void ondemand_readahead(struct readahead_control *ractl,
 			1UL << order);
 	if (index == expected || index == (ra->start + ra->size)) {
 		ra->start += ra->size;
-		ra->size = get_next_ra_size(ra, max_pages);
+		/*
+		 * In the case of MADV_HUGEPAGE, the actual size might exceed
+		 * the readahead window.
+		 */
+		ra->size = max(ra->size, get_next_ra_size(ra, max_pages));
 		ra->async_size = ra->size;
 		goto readit;
 	}