Subject: Re: [PATCH net-next RFC WIP] Patch for XDP support for virtio_net

From: Jesper Dangaard Brouer <[email-masked]>
Date: Wed, 26 Oct 2016 15:52:02 +0200

On Sat, 22 Oct 2016 04:07:23 +0000
Shrijeet Mukherjee <[email-masked]> wrote:

> This patch adds support for xdp ndo and also inserts the xdp program
> call into the merged RX buffers and big buffers paths

I really appreciate you are doing this for virtio_net.

My first question is: Is the (packet) page data writable?
(MST might be able to answer?)

As this is currently an XDP requirement[1].  

> * The small packet skb receive is skipped for now
> * No TX for now

I do see more and more valid use-cases for only implementing XDP_DROP
and not necessarily also implementing XDP_TX.  This does requires that
we implement some kind of feature/capabilities negotiation mechanism[2].

[1] https://prototype-kernel.readthedocs.io/en/latest/networking/XDP/design/requirements.html#write-access-to-packet-data

[2] https://prototype-kernel.readthedocs.io/en/latest/networking/XDP/design/design.html#capabilities-negotiation

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  Author of http://www.iptv-analyzer.org
  LinkedIn: http://www.linkedin.com/in/brouer