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From:   Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Date:   Mon, 7 Sep 2020 11:22:33 +0200
Message-ID: <CA+FuTSfeEuTLAGJZkzoMUvx+0j3dY265i8okPLyDO6S-8KHdbQ@mail.gmail.com>
Subject: Re: [PATCH net-next 0/2] net: two updates related to UDP GSO
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Huazhong Tan <tanhuazhong@huawei.com>,
        David Miller <davem@davemloft.net>,
        Network Development <netdev@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        salil.mehta@huawei.com, yisen.zhuang@huawei.com,
        linuxarm@huawei.com,
        Willem de Bruijn <willemdebruijn.kernel@gmail.com>
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On Sun, Sep 6, 2020 at 8:42 PM Jakub Kicinski <kuba@kernel.org> wrote:
>
> On Sat, 5 Sep 2020 14:11:11 +0800 Huazhong Tan wrote:
> > There are two updates relates to UDP GSO.
> > #1 adds a new GSO type for UDPv6
> > #2 adds check for UDP GSO when csum is disable in netdev_fix_features().
> >
> > Changes since RFC V2:
> > - modifies the timing of setting UDP GSO type when doing UDP GRO in #1.
> >
> > Changes since RFC V1:
> > - updates NETIF_F_GSO_LAST suggested by Willem de Bruijn.
> >   and add NETIF_F_GSO_UDPV6_L4 feature for each driver who support UDP GSO in #1.
> >   - add #2 who needs #1.
>
> Please CC people who gave you feedback (Willem).
>
> I don't feel good about this series. IPv6 is not optional any more.
> AFAIU you have some issues with csum support in your device? Can you
> use .ndo_features_check() to handle this?
>
> The change in semantics of NETIF_F_GSO_UDP_L4 from "v4 and v6" to
> "just v4" can trip people over; this is not a new feature people
> may be depending on the current semantics.
>
> Willem, what are your thoughts on this?

If that is the only reason, +1 on fixing it up in the driver's
ndo_features_check.