Subject: Re: [PATCH v6 net-next 11/14] virtio_net: Accurate ECN flag in virtio_net_hdr

From: "Michael S. Tsirkin" <[email-masked]>
Date: Wed, 8 Jan 2025 07:27:45 -0500

On Mon, Dec 30, 2024 at 09:50:59AM +0000, Chia-Yu Chang (Nokia) wrote:
> >From: Jason Wang <[email-masked]> 
> >Sent: Monday, December 30, 2024 8:52 AM
> >To: Chia-Yu Chang (Nokia) <[email-masked]>
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> >Subject: Re: [PATCH v6 net-next 11/14] virtio_net: Accurate ECN flag in virtio_net_hdr
> >
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> >On Sat, Dec 28, 2024 at 3:13 AM <[email-masked]> wrote:
> >>
> >> From: Chia-Yu Chang <[email-masked]>
> >>
> >> Unlike RFC 3168 ECN, accurate ECN uses the CWR flag as part of the ACE 
> >> field to count new packets with CE mark; however, it will be corrupted 
> >> by the RFC 3168 ECN-aware TSO. Therefore, fallback shall be applied by 
> >> seting NETIF_F_GSO_ACCECN to ensure that the CWR flag should not be 
> >> changed within a super-skb.
> >>
> >> To apply the aforementieond new AccECN GSO for virtio, new featue bits 
> >> for host and guest are added for feature negotiation between driver 
> >> and device. And the translation of Accurate ECN GSO flag between 
> >> virtio_net_hdr and skb header for NETIF_F_GSO_ACCECN is also added to 
> >> avoid CWR flag corruption due to RFC3168 ECN TSO.
> >>
> >> Signed-off-by: Chia-Yu Chang <[email-masked]>
> >> ---
> >>  drivers/net/virtio_net.c        | 14 +++++++++++---
> >>  drivers/vdpa/pds/debugfs.c      |  6 ++++++
> >>  include/linux/virtio_net.h      | 16 ++++++++++------
> >>  include/uapi/linux/virtio_net.h |  5 +++++
> >>  4 files changed, 32 insertions(+), 9 deletions(-)
> >
> >Is there a link to the spec patch? It needs to be accepted first.
> >
> >Thanks
> 
> Hi Jason,
> 
> Thanks for the feedback, I found the virtio-spec in github: https://github.com/oasis-tcs/virtio-spec but not able to find the procedure to propose.
> Could you help to share the procedure to propose spec patch? Thanks.

You post it on virtio-comment for discussion. Github issues are then used
for voting and to track acceptance.
https://github.com/oasis-tcs/virtio-spec/blob/master/README.md#use-of-github-issues

> --
> Chia-Yu