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From: Neal Cardwell <ncardwell@google.com>
To: Apollon Oikonomopoulos <apoikos@dmesg.gr>
Cc: Yuchung Cheng <ycheng@google.com>,
	Netdev <netdev@vger.kernel.org>,
	Eric Dumazet <edumazet@google.com>,
	Soheil Hassas Yeganeh <soheil@google.com>
Subject: Re: TCP sender stuck in persist despite peer advertising non-zero window
Date: Thu, 22 Oct 2020 10:39:51 -0400	[thread overview]
Message-ID: <CADVnQy=owUxBjPcHC1u0Xn_Uwd3wBVoQFO+5Wo-TzO0=1+3HMQ@mail.gmail.com> (raw)
In-Reply-To: <87eelqs9za.fsf@marvin.dmesg.gr>

On Thu, Oct 22, 2020 at 8:47 AM Apollon Oikonomopoulos <apoikos@dmesg.gr> wrote:
>
> Apollon Oikonomopoulos <apoikos@dmesg.gr> writes:
> > We are now running the patched kernel on the machines involved. I want
> > to give it some time just to be sure, so I'll get back to you by
> > Thursday if everything goes well.
>
> It has been almost a week and we have had zero hangs in 60 rsync runs,
> so I guess we can call it fixed. At the same time we didn't notice any
> ill side-effects. In the unlikely event it hangs again, I will let you
> know.

Great. Many thanks for your testing and thorough analysis!

I agree that it's a little surprising that this bug would be there for
so long (looks like since Linux v2.1.8 in Nov 1996), but I also agree
with your analysis about why this might be so.

I have posted the proposed patch here:

  https://patchwork.ozlabs.org/project/netdev/patch/20201022143331.1887495-1-ncardwell.kernel@gmail.com/

best,
neal

      reply	other threads:[~2020-10-22 14:40 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-15 18:23 TCP sender stuck in persist despite peer advertising non-zero window Apollon Oikonomopoulos
2020-10-15 20:22 ` Neal Cardwell
2020-10-15 20:27   ` Soheil Hassas Yeganeh
2020-10-15 21:39   ` Yuchung Cheng
2020-10-15 22:12     ` Apollon Oikonomopoulos
2020-10-15 22:37       ` Neal Cardwell
2020-10-16  7:35         ` Eric Dumazet
2020-10-16 16:57         ` Apollon Oikonomopoulos
2020-10-16 17:54           ` Neal Cardwell
2020-10-22 12:47           ` Apollon Oikonomopoulos
2020-10-22 14:39             ` Neal Cardwell [this message]

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