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Tsirkin" Cc: Jakub Kicinski , davem@davemloft.net, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, ivan@prestigetransportation.com, xiangxia.m.yue@gmail.com, willemb@google.com, edumazet@google.com References: <20210811081623.9832-1-jasowang@redhat.com> <20210811151754.030a22a7@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <20210812004655-mutt-send-email-mst@kernel.org> From: Jason Wang Message-ID: Date: Thu, 12 Aug 2021 14:18:21 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: <20210812004655-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2021/8/12 下午12:50, Michael S. Tsirkin 写道: > On Thu, Aug 12, 2021 at 11:23:04AM +0800, Jason Wang wrote: >> 在 2021/8/12 上午6:17, Jakub Kicinski 写道: >>> On Wed, 11 Aug 2021 16:16:23 +0800 Jason Wang wrote: >>>> Try to fix this by using NETIF_F_GRO_HW instead so we're not >>>> guaranteed to be re-segmented as original. >>> This sentence may need rephrasing. >> >> Right, actually, I meant: >> >> >> Try to fix this by using NETIF_F_GRO_HW instead. But we're not sure the >> packet could be re-segmented to the exact original packet stream. Since it's >> really depends on the bakcend implementation. >> >> >>>> Or we may want a new netdev >>>> feature like RX_GSO since the guest offloads for virtio-net is >>>> actually to receive GSO packet. >>>> >>>> Or we can try not advertise LRO is control guest offloads is not >>>> enabled. This solves the warning but will still slow down the traffic. >>> IMO gro-hw fits pretty well, patch looks good. >> >> If the re-segmentation is not a issue. I will post a formal patch. >> >> Thanks > > It is but the point is even though spec did not require this > we always allowed these configurations > in the past so hopefully most of them are not broken and combine > packets in the same way as GRO. Let's not break them all > in an attempt to catch bad configs, and meanwhile amend > the spec to recommend doing GW GRO. Ok, let me add this in the commit log and send a formal patch. Thanks >