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

From: Ming Lei

Date: Sat Sep 26 2026 - 12:07:00 EST


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.

Also there is risk in 'task_struct *' keyed bpf task storage.

task_work queuing could become tricky too.


Thanks,
Ming