Use virtio_get_config_size() rather than sizeof(struct virtio_snd_config) for the config_size in the vhost-user-snd frontend. The frontend shall rely on device features for the size of the device configuration space. This fixes an issue introduced by commit ab0c7fb2 in which the optional field `control` is added to the virtio_snd_config structure. This breaks vhost-user-device backends that do not implement the `controls` field.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2805 Suggested-by: Stefano Garzarella <sgarz...@redhat.com> Signed-off-by: Matias Ezequiel Vara Larsen <mvara...@redhat.com> --- hw/virtio/vhost-user-snd.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/hw/virtio/vhost-user-snd.c b/hw/virtio/vhost-user-snd.c index 8610370af8..8da4309470 100644 --- a/hw/virtio/vhost-user-snd.c +++ b/hw/virtio/vhost-user-snd.c @@ -16,6 +16,18 @@ #include "standard-headers/linux/virtio_ids.h" #include "standard-headers/linux/virtio_snd.h" +static const VirtIOFeature feature_sizes[] = { + {.flags = 1ULL << VIRTIO_SND_F_CTLS, + .end = endof(struct virtio_snd_config, controls)}, + {} +}; + +static const VirtIOConfigSizeParams cfg_size_params = { + .min_size = endof(struct virtio_snd_config, chmaps), + .max_size = sizeof(struct virtio_snd_config), + .feature_sizes = feature_sizes +}; + static const VMStateDescription vu_snd_vmstate = { .name = "vhost-user-snd", .unmigratable = 1, @@ -23,16 +35,20 @@ static const VMStateDescription vu_snd_vmstate = { static const Property vsnd_properties[] = { DEFINE_PROP_CHR("chardev", VHostUserBase, chardev), + DEFINE_PROP_BIT64("config-controls", VHostUserBase, + parent_obj.host_features, VIRTIO_SND_F_CTLS, false), }; static void vu_snd_base_realize(DeviceState *dev, Error **errp) { VHostUserBase *vub = VHOST_USER_BASE(dev); VHostUserBaseClass *vubs = VHOST_USER_BASE_GET_CLASS(dev); + VirtIODevice *vdev = &vub->parent_obj; vub->virtio_id = VIRTIO_ID_SOUND; vub->num_vqs = 4; - vub->config_size = sizeof(struct virtio_snd_config); + vub->config_size = virtio_get_config_size(&cfg_size_params, + vdev->host_features); vub->vq_size = 64; vubs->parent_realize(dev, errp); -- 2.42.0
