From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [PATCH RFC 2/2] veth: propagate bridge GSO to peer Date: Sun, 26 Nov 2017 20:13:39 -0700 Message-ID: References: <20171126181749.19288-1-sthemmin@microsoft.com> <20171126181749.19288-3-sthemmin@microsoft.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, Stephen Hemminger To: Stephen Hemminger , davem@davemloft.net Return-path: Received: from mail-pg0-f65.google.com ([74.125.83.65]:32845 "EHLO mail-pg0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750914AbdK0DNq (ORCPT ); Sun, 26 Nov 2017 22:13:46 -0500 Received: by mail-pg0-f65.google.com with SMTP id s75so18082266pgs.0 for ; Sun, 26 Nov 2017 19:13:46 -0800 (PST) In-Reply-To: <20171126181749.19288-3-sthemmin@microsoft.com> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: 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 > --- > 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.