Subject: Re: [PATCH net-next 2/2] openvswitch: Fix skb->protocol for vlan frames.

From: Jiri Benc <[email-masked]>
Date: Thu, 24 Nov 2016 17:10:46 +0100

On Tue, 22 Nov 2016 20:09:34 -0800, Jarno Rajahalme wrote:
> Do not set skb->protocol to be the ethertype of the L3 header, unless
> the packet only has the L3 header.  For a non-hardware offloaded VLAN
> frame skb->protocol needs to be one of the VLAN ethertypes.
> 
> Any VLAN offloading is undone on the OVS netlink interface.  Due to
> this all VLAN packets sent to openvswitch module from userspace are
> non-offloaded.

This is exactly why I wanted to always accelerate the vlan tag, the
same way it is done in other parts of the networking stack: to prevent
all those weird corner cases.

Looks to me this is the only real way forward.

This patch is wrong, it would leave skb->protocol as ETH_P_TEB for L2
frames received via ARPHRD_NONE interface.

 Jiri