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Message-ID: <e4b7eddc-3a73-0994-467e-6d65d6ad80c0@tessares.net>
Date:   Thu, 8 Sep 2022 15:56:13 +0200
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Subject: Re: [PATCH net v3] net: mptcp: fix unreleased socket in accept queue
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To:     menglong8.dong@gmail.com, pabeni@redhat.com
Cc:     mathew.j.martineau@linux.intel.com, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, fw@strlen.de,
        peter.krystad@linux.intel.com, netdev@vger.kernel.org,
        mptcp@lists.linux.dev, linux-kernel@vger.kernel.org,
        Menglong Dong <imagedong@tencent.com>,
        Jiang Biao <benbjiang@tencent.com>,
        Mengen Sun <mengensun@tencent.com>
References: <20220907111132.31722-1-imagedong@tencent.com>
From:   Matthieu Baerts <matthieu.baerts@tessares.net>
In-Reply-To: <20220907111132.31722-1-imagedong@tencent.com>
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Hi Menglong,

On 07/09/2022 13:11, menglong8.dong@gmail.com wrote:
> From: Menglong Dong <imagedong@tencent.com>
> 
> The mptcp socket and its subflow sockets in accept queue can't be
> released after the process exit.
> 
> While the release of a mptcp socket in listening state, the
> corresponding tcp socket will be released too. Meanwhile, the tcp
> socket in the unaccept queue will be released too. However, only init
> subflow is in the unaccept queue, and the joined subflow is not in the
> unaccept queue, which makes the joined subflow won't be released, and
> therefore the corresponding unaccepted mptcp socket will not be released
> to.

Thank you for the v3.

Unfortunately, our CI found a possible recursive locking:

> - KVM Validation: debug:
>   - Unstable: 1 failed test(s): selftest_mptcp_join - Critical: 1 Call Trace(s) ❌:
>   - Task: https://cirrus-ci.com/task/5418283233968128
>   - Summary: https://api.cirrus-ci.com/v1/artifact/task/5418283233968128/summary/summary.txt

https://lore.kernel.org/mptcp/4e6d3d9e-1f1a-23ae-cb56-2d4f043f17ae@gmail.com/T/#u

Do you mind looking at it please?

Also, because it is not just a simple fix, may you send any new versions
only to MPTCP mailing list please? So without the other mailing lists
and netdev maintainers to reduce the audience during the development.

Once the patch is ready, we will apply it in MPTCP tree and send it to
netdev. That's what we usually for MPTCP related patches.

Cheers,
Matt
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