Re: [PATCH 1/1] io_uring: delay sqarray static branch disablement

[Jens Axboe <axboe@kernel.dk>]

On 2/15/26 2:56 PM, Pavel Begunkov wrote:
> On 2/15/26 21:48, Jens Axboe wrote:
>> On 2/15/26 2:29 PM, Pavel Begunkov wrote:
>>> io_key_has_sqarray static branch can be easily switched
>>> on/off by the user. Prevent abuse and defer for a bit when it's
>>> disabled.
>>
>> Can we get something in here for the reason for why the change
>> is being made? The commit message really doesn't explain any
>> of this.
> 
> It appeared to be pretty self-explanatory, I can expand, but in
> short you can spam with

It really wasn't! It says "prevent abuse" but is not specific on what
kind of abuse this is at all.

> while (1) {
>     create_ring_with_sq_array();
>     kill_ring();
> }
> 
> and each iteration it'll be patching kernel code, and that
> can be very disruptive for the entire system depending on arch
> and how removal is synchronized.

OK, so that's the abuse being referred to. I could surely find
out by just checking static_branch_slow_dec_deferred() and
friends, but a commit message should stand by itself and not
need that kind of discovery.

Can you just send a v2 with an updated commit message, please?

-- 
Jens Axboe