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Date:   Fri, 22 Jan 2021 18:45:34 -0800
From:   Enke Chen <enkechen2020@gmail.com>
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Eric Dumazet <edumazet@google.com>,
        "David S. Miller" <davem@davemloft.net>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Neal Cardwell <ncardwell@google.com>, enkechen2020@gmail.com
Subject: Re: [PATCH net] tcp: make TCP_USER_TIMEOUT accurate for zero window
 probes
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Hi, Jakub:

On Fri, Jan 22, 2021 at 06:34:24PM -0800, Jakub Kicinski wrote:
> On Fri, 22 Jan 2021 18:28:23 -0800 Enke Chen wrote:
> > Hi, Jakub:
> > 
> > In terms of backporting, this patch should go together with:
> > 
> >     9d9b1ee0b2d1 tcp: fix TCP_USER_TIMEOUT with zero window
> 
> As in it:
> 
> Fixes: 9d9b1ee0b2d1 tcp: fix TCP_USER_TIMEOUT with zero window
> 
> or does it further fix the same issue, so:
> 
> Fixes: 9721e709fa68 ("tcp: simplify window probe aborting on USER_TIMEOUT")
>
> ?

Let me clarify:

1) 9d9b1ee0b2d1 tcp: fix TCP_USER_TIMEOUT with zero window

   fixes the bug and makes it work.

2) The current patch makes the TCP_USER_TIMEOUT accurate for 0-window probes.
   It's independent.

With 1) and 2), the known issues with TCP_USER_TIMEOUT for 0-window probes
would be resolved.

Thanks.   -- Enke