Re: [PATCH 2/3] KVM: Add gsi_msg_pending_bitmap for MSI-X

Sheng Yang
2009-02-18T01:33:44Z

On Wednesday 18 February 2009 02:09:49 Avi Kivity wrote:
> Sheng Yang wrote:
> >>> + if (assigned_dev->irq_requested_type == KVM_ASSIGNED_DEV_MSIX) {
> >>> + u32 gsi;
> >>> + gsi = find_gsi_from_host_irq(assigned_dev, irq);
> >>> + if (gsi == 0)
> >>> + return IRQ_HANDLED;
> >>
> >> So you chose GSI == 0 as invalid because of x86 assumptions? Or is there
> >> any other reason?
> >
> > Yeah, it based on x86 and IA64 IRQ 0 can't be used by MSI-X. And only x86
> > support MSI-X now(and IA64 would follow later).
>
> gsi != irq... as used in kvm it is just a cookie and is never visible to
> the guest. I'd prefer an illegal value here.
>
>
> Also, please repost the entire patchset so I can be sure I apply the
> latest; too many versions floating around.

OK. And please don't forget there is a patchset named "Optimize and unify
IOAPIC/MSI delivery" before this one. :)

--
regards
Yang, Sheng