Re: [PATCH v5 1/5] arm64: Add framework to turn IPI as NMI

[Marc Zyngier]

On 2020-10-20 07:43, Sumit Garg wrote:
> On Mon, 19 Oct 2020 at 17:07, Marc Zyngier <maz@xxxxxxxxxx> wrote:

[...]

> > > +{
> > > +     if (!ipi_desc)
> > > +             return;
> > > +
> > > +     if (is_nmi) {
> > > +             if (!prepare_percpu_nmi(ipi_id))
> > > +                     enable_percpu_nmi(ipi_id, IRQ_TYPE_NONE);
> > > +     } else {
> > > +             enable_percpu_irq(ipi_id, IRQ_TYPE_NONE);
> >
> > I'm not keen on this. Normal IRQs can't reliably work, so why do you
> > even bother with this?
>
> Yeah I agree but we need to support existing functionality for kgdb
> roundup and sysrq backtrace using normal IRQs as well.

When has this become a requirement? I don't really see the point in
implementing something that is known not to work.

        M.
--
Jazz is not dead. It just smells funny...