Re: issues with vxlan RX checksum offload under OVS datapath

[Or Gerlitz <or.gerlitz@gmail.com>]

On Tue, Jan 21, 2014 at 7:30 PM, Pravin Shelar <pshelar@nicira.com> wrote:
> On Sun, Jan 19, 2014 at 2:05 PM, Or Gerlitz <ogerlitz@mellanox.com> wrote:

>> While testing the gro udp patches over a setup with openvswitch I noted that
>> the RX checksum offload support introduced by Joseph's commit 0afb166
>> "vxlan: Add capability of Rx checksum offload for inner packet" works fine
>> when you use a setup made of
>> NIC --> IP stack --> vxlan device --> bridge --> tap
>> but not when its
>> NIC --> IP stack --> ovs vxlan port --> OVS DP --> tap
>> I narrowed it down to the fact the when going the OVS pathskb->encapsulation
>> remains true also after the decap is done. Basically, this is the original hunk
[...]
>>> +       skb->encapsulation = 0;
[...]

>> Moving this to shared code (while removing the check for
>> vxlan->dev->features) made things to work on my setup, but this misses one
>> of the original conditions, ideas?

> I kept csum check in vxlan-device recv path for same reason. As of now
> there is no efficient way to get ovs-dev features.
> May be we can cache device features in struct datapath from datapath-netdev.

To be a bit more precise/concrete here, do we agree that the both paths must do

   skb->encapsulation = 0;

which is done now only by the non-ovs path

Or.