Re: [PATCH 2/4] cpu/hotplug: CPUHP_BRINGUP_CPU exception in fail injection

From: Peter Zijlstra
Date: Wed Jan 20 2021 - 12:35:02 EST


On Wed, Jan 20, 2021 at 03:17:24PM +0000, Vincent Donnefort wrote:
> On Wed, Jan 20, 2021 at 01:58:35PM +0100, Peter Zijlstra wrote:
> > On Mon, Jan 11, 2021 at 05:10:45PM +0000, vincent.donnefort@xxxxxxx wrote:

> > > + if (cpuhp_is_atomic_state(fail) ||
> > > + (fail == CPUHP_BRINGUP_CPU && st->state > CPUHP_BRINGUP_CPU))
> > > return -EINVAL;
> >
> > Should we instead disallow failing any state that has .cant_stop ?
>
> We would reduce the scope of what can be tested: bringup_cpu() and
> takedown_cpu() are both marked as "cant_stop". Still, those callbacks are
> allowed to fail.

Fair enough. I suppose we can add an additional cant_fail field, but I'm
not sure that's worth the effort over this.