diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 67e794d..8726fd7 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2134,6 +2134,7 @@
 		return -EINVAL;
 	set_capacity(mddev->gendisk, mddev->array_sectors);
 	mddev->changed = 1;
+	revalidate_disk(mddev->gendisk);
 	if (sectors > mddev->dev_sectors &&
 	    mddev->recovery_cp == MaxSector) {
 		mddev->recovery_cp = mddev->dev_sectors;