diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index eb023d267369..631dca2e4e84 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -494,6 +494,7 @@ static ssize_t nullb_device_power_store(struct config_item *item,
 
 		set_bit(NULLB_DEV_FL_CONFIGURED, &dev->flags);
 		dev->power = newp;
+		ret = count;
 	} else if (dev->power && !newp) {
 		if (test_and_clear_bit(NULLB_DEV_FL_UP, &dev->flags)) {
 			dev->power = newp;