Re: [PATCH -rcu/dev 0/4] hazptrtorture: Fix shutdown hang and catch slot owner race

[Andrea Parri]

On Thu, Oct 29, 2026 at 05:58:27PM +0800, KunWu Chan wrote:
> I ran into both issues independently while developing new shared-scan
> hazptr series and its torture-test scenarios.

Thank you for testing these, and for the arm64 data points!

[...]

> Paul's concern about `torture_must_stop()` is valid: `fullstop` can make the
> drainer exit before the readers have stopped, so its exit-time flush is not
> necessarily final. The reader-exit approach looks worth testing against both
> the forced-slowpath case and the PREEMPT scenario Andrea reported.

do_pending does leave its loop then, but v1's for_each_possible_cpu()
pass comes after torture_kthread_stopping(), which returns only once
hazptr_torture_cleanup() stops do_pending, after the readers.  Either
way, I have been testing Paul's suggestion of a pass after each
reader's loop, without v1's pass in do_pending.

[...]

> These tests independently reproduced both issues in my setup. I'll check the
> final cleanup approach against the forced-slowpath scenario as the
> series settles.

That would be very helpful, thank you.

Thanks,
  Andrea