Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Sun, 6 Sep 2020 11:41:53 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Huazhong Tan <tanhuazhong@huawei.com>
Cc:     <davem@davemloft.net>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <salil.mehta@huawei.com>,
        <yisen.zhuang@huawei.com>, <linuxarm@huawei.com>,
        Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Subject: Re: [PATCH net-next 0/2] net: two updates related to UDP GSO
Message-ID: <20200906114153.7dccce5d@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
In-Reply-To: <1599286273-26553-1-git-send-email-tanhuazhong@huawei.com>
References: <1599286273-26553-1-git-send-email-tanhuazhong@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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?