From 486d2e632ca157558a738626c092973f309f3b45 Mon Sep 17 00:00:00 2001
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: Wed, 15 Oct 2014 10:22:33 +1030
Subject: [PATCH] virtio_balloon: enable VQs early on restore

virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after resume returns, virtio balloon
violated this rule by adding bufs, which causes the VQ to be used
directly within restore.

To fix, call virtio_device_ready before using VQ.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
 drivers/virtio/virtio_balloon.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 25ebe8eecdb7..f4a28af4865e 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -538,6 +538,8 @@ static int virtballoon_restore(struct virtio_device *vdev)
 	if (ret)
 		return ret;
 
+	virtio_device_ready(vdev);
+
 	fill_balloon(vb, towards_target(vb));
 	update_balloon_size(vb);
 	return 0;