virtio: set FEATURES_OK

set FEATURES_OK as per virtio 1.0 spec

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>

1 files changed, 22 insertions, 7 deletions

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 746d350c8062..9248125d29c9 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -160,6 +160,7 @@ static int virtio_dev_probe(struct device *_d)
         struct virtio_device *dev = dev_to_virtio(_d);
         struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
         u64 device_features;
+        unsigned status;
 
         /* We have a driver! */
         add_status(dev, VIRTIO_CONFIG_S_DRIVER);
@@ -183,18 +184,32 @@ static int virtio_dev_probe(struct device *_d)
 
         dev->config->finalize_features(dev);
 
+        if (virtio_has_feature(dev, VIRTIO_F_VERSION_1)) {
+                add_status(dev, VIRTIO_CONFIG_S_FEATURES_OK);
+                status = dev->config->get_status(dev);
+                if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) {
+                        dev_err(_d, "virtio: device refuses features: %x\n",
+                               status);
+                        err = -ENODEV;
+                        goto err;
+                }
+        }
+
         err = drv->probe(dev);
         if (err)
-                add_status(dev, VIRTIO_CONFIG_S_FAILED);
-        else {
-                add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
-                if (drv->scan)
-                        drv->scan(dev);
+                goto err;
 
-                virtio_config_enable(dev);
-        }
+        add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
+        if (drv->scan)
+                drv->scan(dev);
+
+        virtio_config_enable(dev);
 
+        return 0;
+err:
+        add_status(dev, VIRTIO_CONFIG_S_FAILED);
         return err;
+
 }
 
 static int virtio_dev_remove(struct device *_d)