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
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 useful optimization on hosts that don't have
hardware-accelerated E
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 useful optimization on hosts that
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_return(&hv->synic_auto_eoi_used) == 1)
> +
Cool! Thanks for correction, yeah, APICV_INHIBIT_REASON_HYPERV setting is
per-VM while synic is per-vCPU. Since the machine with AVIC is not in my hands
today, I will test it hopefully by end of this week:)
BR,
Kechen
>-Original Message-
>From: Vitaly Kuznetsov
>Sent: Thursday, Februar
