Re: [RFC PATCH 00/15] io_uring: thread identity handoff for blocking inline issue

[Jens Axboe]

On 9/26/26 10:04 AM, Ming Lei wrote:
> On Fri, Sep 11, 2026 at 09:40:50AM -0600, Jens Axboe wrote:
>> Hi,
>>
> 
> ...
> 
>>
>> This is obviously an RFC, in terms of what I'd love people to take a
>> closer look at:
>>
>> - The scheduler hook and the identity move itself, kernel/thread_handoff.c.
>>   Is the set of refused states complete enough, and is moving
>>   thread group leadership this way (the leader must stay first on
>>   ->thread_head, like de_thread() keeps it) acceptable / kosher.
>> - The x86 and arm64 register state handling. x86 refuses AMX users,
>>   and arm64 refuses SME.
>> - Whether anyone relies on a task's user identity staying on one
>>   task_struct in ways not covered above in the series.
> 
> This way may break ublk server given 'task_struct *' can be changed
> because the server issues blocking OP(fallocate, ...), then the
> `current` check in ublk_dispatch_req() can be hit.

Yep, which is why is isn't enabled there.

> Also there is risk in 'task_struct *' keyed bpf task storage.
> 
> task_work queuing could become tricky too.

Like the above, the series does attempt to handle that.

-- 
Jens Axboe