Re: [RFC PATCH mptcp-next] mptcp: annotate data-races around sysctl reads

[Matthieu Baerts <matttbe@kernel.org>]

Hi Tao, Gang,

Thank you for looking at this!

On 14/08/2026 07:26, Tao Cui wrote:
> Hi Gang,
> 
> 在 2026/8/14 11:51, gang.yan@linux.dev 写道:
>> August 14, 2026 at 11:27 AM, "Tao Cui" <cui.tao@linux.dev mailto:cui.tao@linux.dev?to=%22Tao%20Cui%22%20%3Ccui.tao%40linux.dev%3E > wrote:
>>
>> Hi, Tao
>>
>> Thanks for your patch, but it has been submitted by Matt before in [1].

Thank you for the review!

>> I think Matt wanted change the PM and sched sysctl from string to atomically,
>> that may need another patches (READ_ONCE is not enough), right? If no, you can
>> wait for the other maintainers' reply.

Correct.

>> If yes, I still think this patch should keep author as matt, the rest of
>> others can be yours.
>>
>> Note: Some patches about sched is only in our export branch, not mainlined,
>> so it's better to do your work based on it.
>>
> 
> Thanks for the review. I did see #626 before sending and referenced
> it, I just read its scope wrong: I assumed the patch it links was only
> about the string sysctls and missed that the numeric readers were
> already covered there.

Do you plan to work on that? If yes, that's great, thank you. Just one
thing: if you are working on addressing an issue that is on GitHub, do
you mind adding a comment there to say that you are working on it,
please? Just to avoid having multiple people doing the same thing. (Just
to be clear: I'm not working on it.)

> And thanks for the export branch tip, I'd only been looking at
> mainline and didn't know some of the sched patches are only in export.
> 
> The only bit mine adds is the WRITE_ONCE() on the pm_type store in
> proc_path_manager(), to pair with the mptcp_get_pm_type() read. Matt,
> if you want that too just grab it, otherwise I can send it as a small
> follow-up.

Good catch! If you are planning to work on the other remaining sysctl,
do you mind taking my patch, add the missing WRITE_ONCE() to it + add
your co-developed-by + signoff to it, then add your new patch(es) on top
of it and send everything (including the first patch), please?

Cheers,
Matt
-- 
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