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Message-ID: <b1342885-3aed-9c34-8f6a-aa681369ad27@163.com>
Date:   Thu, 24 Mar 2022 10:33:48 +0800
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Subject: Re: [PATCH net-next] tcp: make tcp_rcv_state_process() drop monitor
 friendly
To:     Eric Dumazet <edumazet@google.com>
Cc:     David Ahern <dsahern@kernel.org>, Jakub Kicinski <kuba@kernel.org>,
        Menglong Dong <menglong8.dong@gmail.com>,
        netdev <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
References: <3eb95fd0-2046-c000-9c0b-c7c7e05ce04a@163.com>
 <CANn89i+v=yOd8=-i9cd=vL9U7Q8W0RRNco6CVFv4+Cx6Dj0z5A@mail.gmail.com>
From:   Jianguo Wu <wujianguo106@163.com>
In-Reply-To: <CANn89i+v=yOd8=-i9cd=vL9U7Q8W0RRNco6CVFv4+Cx6Dj0z5A@mail.gmail.com>
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Hi,
    Thanks for your reply. This is more complicated than I thought, i will do some more dig.

在 2022/3/23 21:40, Eric Dumazet 写道:
> On Wed, Mar 23, 2022 at 6:05 AM Jianguo Wu <wujianguo106@163.com> wrote:
>>
>> From: Jianguo Wu <wujianguo@chinatelecom.cn>
>>
>> In tcp_rcv_state_process(), should not call tcp_drop() for same case,
>> like after process ACK packet in TCP_LAST_ACK state, it should call
>> consume_skb() instead of tcp_drop() to be drop monitor friendly,
>> otherwise every last ack will be report as dropped packet by drop monitor.
>>
>> Signed-off-by: Jianguo Wu <wujianguo@chinatelecom.cn>
>> ---
> 
> 1) net-next is closed
> 
> 2) Same remarks as for the other patch.
>    You mark the packet as consumed, while maybe we had to throw away
> some payload from it ?
> 
> You will have to wait for net-next being open,
> then send patches with one change at a time, with clear explanations
> and possibly packetdrill tests.
> 
> I am concerned about all these patches making future backports
> difficult because of merge conflicts.