7/20/25 12:44 PM, Akihiko Odaki wrote:
> On 2025/07/18 17:52, Paolo Abeni wrote:
>> @@ -3333,26 +3362,23 @@ virtio_load(VirtIODevice *vdev, QEMUFile *f, int
>> version_id)
>> vdev->device_endian = virtio_default_endian();
>> }
>>
>> - if (virtio_64bit_features_needed(vdev)) {
>> - /*
>> - * Subsection load filled vdev->guest_features. Run them
>> - * through virtio_set_features to sanity-check them against
>> - * host_features.
>> - */
>> - uint64_t features64 = vdev->guest_features;
>> - if (virtio_set_features_nocheck_maybe_co(vdev, features64) < 0) {
>> - error_report("Features 0x%" PRIx64 " unsupported. "
>> - "Allowed features: 0x%" PRIx64,
>> - features64, vdev->host_features);
>> - return -1;
>> - }
>> - } else {
>> - if (virtio_set_features_nocheck_maybe_co(vdev, features) < 0) {
>> - error_report("Features 0x%x unsupported. "
>> - "Allowed features: 0x%" PRIx64,
>> - features, vdev->host_features);
>> - return -1;
>> - }
>> + /*
>> + * Avoid silently breaking migration should the feature space increase
>> + * even more in the (far away) future
>> + */
>> + QEMU_BUILD_BUG_ON(VIRTIO_FEATURES_DWORDS != 2);
>
> This should be moved to around virtio_128bit_features_needed() and
> vmstate_virtio_128bit_features as they make assumptions on the feature
> space while virtio_load() doesn't.
Please allow me the following dumb question to try to avoid more
iterations for small changes. I guess moving the above inside
virtio_128bit_features_needed() would suffice?
Thanks,
Paolo
