Re: [PATCH] virtio-net: drop legacy features in virtio 1 mode

[Jason Wang]

On 2016å11æ04æ 18:55, Michael S. Tsirkin wrote:
> Virtio 1.0 spec says VIRTIO_F_ANY_LAYOUT and VIRTIO_NET_F_GSO are
> legacy-only feature bits. Do not negotiate them in virtio 1 mode.  Note
> this is a spec violation so we need to backport it to stable/downstream
> kernels.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
> ---
>   drivers/net/virtio_net.c | 30 ++++++++++++++++++++----------
>   1 file changed, 20 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 7a00365..b19fb4d 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -2089,23 +2089,33 @@ static struct virtio_device_id id_table[] = {
>   	{ 0 },
>   };
>   
> +#define VIRTNET_FEATURES \
> +	VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
> +	VIRTIO_NET_F_MAC, \
> +	VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
> +	VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
> +	VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
> +	VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
> +	VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
> +	VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
> +	VIRTIO_NET_F_CTRL_MAC_ADDR, \
> +	VIRTIO_NET_F_MTU
> +
>   static unsigned int features[] = {
> -	VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
> -	VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
> -	VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
> -	VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
> -	VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
> -	VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
> -	VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
> -	VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ,
> -	VIRTIO_NET_F_CTRL_MAC_ADDR,
> +	VIRTNET_FEATURES,
> +};
> +
> +static unsigned int features_legacy[] = {
> +	VIRTNET_FEATURES,
> +	VIRTIO_NET_F_GSO,
>   	VIRTIO_F_ANY_LAYOUT,
> -	VIRTIO_NET_F_MTU,
>   };
>   
>   static struct virtio_driver virtio_net_driver = {
>   	.feature_table = features,
>   	.feature_table_size = ARRAY_SIZE(features),
> +	.feature_table_legacy = features_legacy,
> +	.feature_table_size_legacy = ARRAY_SIZE(features_legacy),
>   	.driver.name =	KBUILD_MODNAME,
>   	.driver.owner =	THIS_MODULE,
>   	.id_table =	id_table,

Acked-by: Jason Wang <jasowang@xxxxxxxxxx>