From: Michael S. Tsirkin <mst@redhat.com>
Date: Mon, 12 Jan 2015 14:23:37 +0000 (+0200)
Subject: virtio/net: verify device has config space
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=6ba422489bcaebd89142cc0aeae9095d03c8301a;p=linux-beck.git

virtio/net: verify device has config space

Some devices might not implement config space access
(e.g. remoteproc used not to - before 3.9).
virtio/net needs config space access so make it
fail gracefully if not there.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 5ca97713bfb3..9bc107200709 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1713,6 +1713,12 @@ static int virtnet_probe(struct virtio_device *vdev)
 	struct virtnet_info *vi;
 	u16 max_queue_pairs;
 
+	if (!vdev->config->get) {
+		dev_err(&vdev->dev, "%s failure: config access disabled\n",
+			__func__);
+		return -EINVAL;
+	}
+
 	if (!virtnet_validate_features(vdev))
 		return -EINVAL;