virtio: reenable config if freezing device failed

commit 310227f42882c52356b523e2f4e11690eebcd2ab upstream.

Currently, we don't reenable the config if freezing the device failed.

For example, virtio-mem currently doesn't support suspend+resume, and
trying to freeze the device will always fail. Afterwards, the device
will no longer respond to resize requests, because it won't get notified
about config changes.

Let's fix this by re-enabling the config if freezing fails.

Fixes: 22b7050a024d ("virtio: defer config changed notifications")
Cc: <stable@kernel.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20240213135425.795001-1-david@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index c2b733ef95b0dbe8a9925d6a8f516018ef58b3df..2f8f3bd56b00edd8e1c9f53eb65fa6bba3f4bcdf 100644 (file)
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -455,13 +455,19 @@ EXPORT_SYMBOL_GPL(unregister_virtio_device);
 int virtio_device_freeze(struct virtio_device *dev)
 {
        struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+       int ret;
 
        virtio_config_disable(dev);
 
        dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
 
-       if (drv && drv->freeze)
-               return drv->freeze(dev);
+       if (drv && drv->freeze) {
+               ret = drv->freeze(dev);
+               if (ret) {
+                       virtio_config_enable(dev);
+                       return ret;
+               }
+       }
 
        return 0;
 }