On 11/26/17 11:17 AM, Stephen Hemminger wrote:
> This allows veth device in containers to see the GSO maximum
> settings of the actual device being used for output.
>
> Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
> ---
> drivers/net/veth.c | 72
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 72 insertions(+)
>
> diff --git a/drivers/net/veth.c b/drivers/net/veth.c
> index f5438d0978ca..0c9ce156943b 100644
> --- a/drivers/net/veth.c
> +++ b/drivers/net/veth.c
> @@ -511,17 +511,89 @@ static struct rtnl_link_ops veth_link_ops = {
> .get_link_net = veth_get_link_net,
> };
>
> +/* When veth device is added to a bridge or other master device
> + * then reflect the GSO max values from the upper device
> + * to the other end of veth pair.
> + */
> +static void veth_change_upper(struct net_device *dev,
> + const struct netdev_notifier_changeupper_info *info)
> +{
> + struct net_device *upper = info->upper_dev;
> + struct net_device *peer;
> + struct veth_priv *priv;
> +
> + if (dev->netdev_ops != &veth_netdev_ops)
> + return;
> +
> + priv = netdev_priv(dev);
> + peer = rtnl_dereference(priv->peer);
> + if (!peer)
> + return;
> +
> + if (upper) {
> + peer->gso_max_segs = upper->gso_max_segs;
> + peer->gso_max_size = upper->gso_max_size;
> + } else {
> + peer->gso_max_segs = GSO_MAX_SEGS;
> + peer->gso_max_size = GSO_MAX_SIZE;
> + }
veth devices can be added to a VRF instead of a bridge, and I do not
believe the gso propagation works for L3 master devices.
>From a quick grep, team devices do not appear to handle gso changes either.
