Re: [PATCH v2 27/39] xen/riscv: introduce arch_move_irqs()

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

On 9/14/26 2:07 PM, Jan Beulich wrote:
> On 27.08.2026 17:21, Oleksii Kurochko wrote:
> > When migrating a vCPU between pCPUs the hypervisor must also migrate
> > the associated virtual interrupt state. arch_move_irqs() is the
> > per-arch hook called by generic code to trigger that.
> >
> > Replace the static inline BUG_ON placeholder in asm/irq.h with a real
> > implementation in intc.c dispatching through a new move_irqs vintc_ops
> > callback. Wire it up in vAPLIC, which delegates to imsic_migrate_vcpu()
> > which itself still a stub to be implemented in follow-up patches.
> >
> > Note that technically ASSERT() in arch_move_irqs() could be skipped as
> > it will be anyway NULL pointer dereference (and a trap will occur) if
> > something isn't properly initialized but sometimes it is harder to
> > find place where NULL pointer derefence happened as it isn't
> > guaraunted that all necessary registers will be filled with something
> > useful.
> > As at the moment I don't find any case when ->move_irqs() could be
> > skipped, the check that ->move_irq isn't NULL is added to ASSERT()
> > instead of adding "if ( ...->move_irq) vitnc->ops->move_irqs(v)".
> All of these two paragraphs look stale / inapllicable; ...
>
> > --- a/xen/arch/riscv/intc.c
> > +++ b/xen/arch/riscv/intc.c
> > @@ -192,3 +192,11 @@ void vintc_ctxt_switch_to(struct vcpu *v)
> >   
> >       ops->ctxt_switch_to(v);
> >   }
> > +
> > +/* Move vCPU's IRQs from one pCPU to another */
> > +void arch_move_irqs(struct vcpu *v)
> > +{
> > +    const struct vintc_ops *ops = v->domain->arch.vintc->ops;
> > +
> > +    ops->move_irqs(v);
> > +}
> There's no ASSERT() here (and I'd prefer if none was added). With the
> description pruned:
I will drop last two paragraphs. They are really stale.

> Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
Thanks.

~ Oleksii
> Jan