Re: [6.5-rc5 regression] core dump hangs (was Re: [Bug report] fstests generic/051 (on xfs) hang on latest linux v6.5-rc5+)

From: Jens Axboe
Date: Mon Jun 12 2023 - 13:30:24 EST


On 6/12/23 10:57 AM, Linus Torvalds wrote:
> On Mon, Jun 12, 2023 at 9:45 AM Jens Axboe <axboe@xxxxxxxxx> wrote:
>>
>> You snipped the suspicion in my reply on why that exists, to avoid
>> io_wq_worker_sleeping() triggering.
>
> I'm not seeing why triggering io_wq_worker_sleeping() should even be a
> problem in the first place.
>
> I suspect that is entirely historical too, and has to do with how it
> used to do that
>
> struct io_worker *worker = kthread_data(tsk);
> struct io_wqe *wqe = worker->wqe;
>
> back in the bad old days of kthreads.
>
> But yeah, I don't know that code.

Looks fine to me to just kill it indeed, whatever we did need this
for is definitely no longer the case. I _think_ we used to have
something in the worker exit that would potentially sleep which
is why we killed it before doing that, now it just looks like dead
code.

--
Jens Axboe