diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 98da5f5d847d2..69e9abf00c744 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -3755,6 +3755,8 @@ static int run(struct mddev *mddev)
 		set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
 		mddev->sync_thread = md_register_thread(md_do_sync, mddev,
 							"reshape");
+		if (!mddev->sync_thread)
+			goto out_free_conf;
 	}
 
 	return 0;
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 0841d8f10a58c..5e65dc6def7ee 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -6973,6 +6973,8 @@ static int run(struct mddev *mddev)
 		set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
 		mddev->sync_thread = md_register_thread(md_do_sync, mddev,
 							"reshape");
+		if (!mddev->sync_thread)
+			goto abort;
 	}
 
 	/* Ok, everything is just fine now */