diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 4d78b5583dc6..f58778b57375 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1764,7 +1764,7 @@ static void null_del_dev(struct nullb *nullb)
 
 	dev = nullb->dev;
 
-	ida_simple_remove(&nullb_indexes, nullb->index);
+	ida_free(&nullb_indexes, nullb->index);
 
 	list_del_init(&nullb->list);
 
@@ -2103,7 +2103,7 @@ static int null_add_dev(struct nullb_device *dev)
 	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, nullb->q);
 
 	mutex_lock(&lock);
-	rv = ida_simple_get(&nullb_indexes, 0, 0, GFP_KERNEL);
+	rv = ida_alloc(&nullb_indexes, GFP_KERNEL);
 	if (rv < 0) {
 		mutex_unlock(&lock);
 		goto out_cleanup_zone;