Re: [Qemu-devel] [PATCH 05/23] hyperv: ensure VP index equal to QEMU cpu_index

[Paolo Bonzini]

On 14/06/2017 15:11, Igor Mammedov wrote:
>> No, KVM really uses the VCPU _index_ for HV_X64_MSR_VP_INDEX:
>
> and as you pointed out that works just by luck,
> as soon as we there would be out of order created CPUs
> returned value won't match cpu_index.
> 
> So instead of spreading this nonsense out to QEMU, is it possible
> to fix kernel(kvm+guest) to use apic_id instead?

Yes, definitely.  At this point let's add a new "KVM_CAP_HYPERV_SYNIC2"
capability and declare the old one broken, that will make things easier.

Paolo