virtio/console: verify device has config space
authorMichael S. Tsirkin <mst@redhat.com>
Mon, 12 Jan 2015 14:23:37 +0000 (16:23 +0200)
committerRusty Russell <rusty@rustcorp.com.au>
Wed, 21 Jan 2015 05:58:46 +0000 (16:28 +1030)
Some devices might not implement config space access
(e.g. remoteproc used not to - before 3.9).
virtio/console 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>
drivers/char/virtio_console.c

index de03df9dd7c9614e290a7c60ddee6a1564c0f5f2..26afb56a807300026507fdf8624e8a597d1acdc0 100644 (file)
@@ -1986,6 +1986,12 @@ static int virtcons_probe(struct virtio_device *vdev)
        bool multiport;
        bool early = early_put_chars != NULL;
 
+       if (!vdev->config->get) {
+               dev_err(&vdev->dev, "%s failure: config access disabled\n",
+                       __func__);
+               return -EINVAL;
+       }
+
        /* Ensure to read early_put_chars now */
        barrier();