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

Avi Kivity
2009-02-17T18:09:20Z

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.

--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.