Paolo Bonzini writes:
> On 03/02/21 07:40, Kechen Lu wrote:
>> From the above observations, trying to see if there's a way for
>> enabling AVIC while also having the most optimized clock source for
>> windows guest.
>>
>
> You would have to change KVM, so that AVIC is only disabled if Auto-EOI
Kechen Lu writes:
> Hi Vitaly and Paolo,
>
> Thanks so much for quick reply. This makes sense to me. From my
> understanding, basically this can be two part of it to resolve it.
>
> First, we make sure to set and expose 0x4004.EAX Bit9 to windows guest,
> like in kvm_vcpu_ioctl_get_hv_cpui
Paolo Bonzini writes:
> On 04/02/21 13:24, Vitaly Kuznetsov wrote:
>> I checked Linux VMs on genuine Hyper-V and surprisingly
>> 'HV_DEPRECATING_AEOI_RECOMMENDED' is not exposed.
>
> Did the host have APICv/AVIC (and can Hyper-V use AVIC)? AutoEOI is
> still a
Vitaly Kuznetsov writes:
> +
> + auto_eoi_new = bitmap_weight(synic->auto_eoi_bitmap, 256);
> +
> + /* Hyper-V SynIC auto EOI SINT's are not compatible with APICV */
> + if (!auto_eoi_old && auto_eoi_new) {
> + if (atomic_inc_ret
Kechen Lu writes:
> Hi Vitaly and Paolo,
>
> Sorry for the delay in response, finally got chance to access a machine with
> AVIC, and was able to test out the patch and reconfirm through some
> benchmarks and tests again today:)
>
> In summary, this patch works well and resolves the issues o
