Re: [PATCH bpf 1/2] bpf: drop duplicate check_app_limited in tcp_bpf_push

[Matthieu Baerts <matttbe@kernel.org>]

Hi Gang, Jiayuan, Geliang,

On 14/09/2026 10:45, gang.yan@linux.dev wrote:
> September 14, 2026 at 4:24 PM, "Jiayuan Chen" <jiayuan.chen@linux.dev mailto:jiayuan.chen@linux.dev?to=%22Jiayuan%20Chen%22%20%3Cjiayuan.chen%40linux.dev%3E > wrote:
> 
>> Same as the tls one: this looks like a cleanup to me. Is there a real regression that affects kernel or user behavior?
>>
>> Do we really need a Fixes tag?
>>
> Hi Jiayuan,
> 
> It's a part of the thread in [1], just kindly remind that there had some comments from Matt:
> 
> '''
> Also, should this be seen as a fix? From what I understand, some
> behaviours have changed, and it is only recently that this call is no
> longer needed.
> '''
> 
> From my view, it seems like that there have some misses in the 'fixed' commit, so the fix tag
> should be kept, right?

When I first saw the modification, it fell like Geliang was fixing
something, hence my question. It is indeed fixing something, but if it
"just" avoids extra checks that are now useless, I agree that it doesn't
need to carry the fixes tag. (Except if it creates a noticeable perf
regression, but I don't think so here.)

If the Fixes tag is removed, it is always good to mention this commit to
help with the context (and just in case if this patch can help with the
backports). And also good to mention c5c37af6ecad9 ("tcp: Convert
do_tcp_sendpages() to use MSG_SPLICE_PAGES") in the commit message as well.

Cheers,
Matt
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