diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 67414616eb35..717787d09e0f 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -3798,6 +3798,8 @@ static int raid10_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 4afc419da60f..9ec74dfe94f4 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -6977,6 +6977,8 @@ static int raid5_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 */