Re: [PATCH 4/8] KVM: PCIPT: fix interrupt handling

Ben-Ami Yassour
2008-07-24T14:25:46Z

On Thu, 2008-07-24 at 19:01 +0530, Amit Shah wrote:
> * On Thursday 24 Jul 2008 16:58:57 Ben-Ami Yassour wrote:
> > On Wed, 2008-07-23 at 19:07 +0530, Amit Shah wrote:
> > > * On Wednesday 16 Jul 2008 18:47:01 Ben-Ami Yassour wrote:
> > > >
> > > > if (irqchip_in_kernel(kvm)) {
> > > > + match->pt_dev.guest.irq = pci_pt_dev->guest.irq;
> > > > + match->pt_dev.host.irq = dev->irq;
> > > > + if (kvm->arch.vioapic)
> > > > + kvm->arch.vioapic->ack_notifier = kvm_pci_pt_ack_irq;
> > > > + if (kvm->arch.vpic)
> > > > + kvm->arch.vpic->ack_notifier = kvm_pci_pt_ack_irq;
> > > > +
> > >
> > > We shouldn't register this notifier unless we get the irq below to avoid
> > > unneeded function calls and checks.
> >
> > Note: This code was changed in the last version of the code but the
> > comment is still relevant.
> >
> > Do you mean that we need to postpone registering the notification?
>
> I mean we can register these function pointers after the request_irq succeeds.

request_irq should be the last initialization operation, since every
thing should be ready when in case an interrupt is received

>
> > In the case of an assigned device this is means the we postpone it for a
> > few seconds, and implementing it like above it cleaner. So I don't see
> > the real value in postponing it.
>
> Sorry, don't get what you mean here.
never mind... see the answer is above.