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Date: Thu, 25 Jul 2013 16:12:49 +0800
From: Jason Wang <jasowang@redhat.com>
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To: Paolo Bonzini <pbonzini@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>, KY Srinivasan <kys@microsoft.com>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
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Subject: Re: [PATCH 4/4] x86: properly handle kvm emulation of hyperv
References: <1374572465-15278-1-git-send-email-jasowang@redhat.com> <1374572465-15278-4-git-send-email-jasowang@redhat.com> <bd93bc49300a4d99996cc4f57c19a008@SN2PR03MB061.namprd03.prod.outlook.com> <51EE97BD.4050402@zytor.com> <51EF59FB.8040207@redhat.com> <51EF5C9C.6070403@zytor.com> <51EF7A2A.6040003@redhat.com> <51EF7CFB.8030104@redhat.com> <ddd4ff1d4b124faeb18e6a0ba8ae2128@BLUPR03MB050.namprd03.prod.outlook.com> <ba894640-b367-44f0-a5e2-89a2edf4951a@email.android.com> <f69678c6673e4168ae244fb6325060bc@BLUPR03MB050.namprd03.prod.outlook.com> <889e20ee-7655-4fdc-b30a-150b8604ca0f@email.android.com> <51F0DAD1.8080108@redhat.com>
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On 07/25/2013 03:59 PM, Paolo Bonzini wrote:
> Il 24/07/2013 23:37, H. Peter Anvin ha scritto:
>> What I'm suggesting is exactly that except that the native hypervisor is later in CPUID space.
> Me too actually.
>
> I was just suggesting an implementation of the idea (that takes into
> account hypervisors detected by other means than CPUID).
>
> Paolo

This make sense, will send V2.

Thanks
>> KY Srinivasan <kys@microsoft.com> wrote:
>>> As Paolo suggested if there were some priority encoded, the guest could make an
>>> informed decision. If the guest under question can run on both hypervisors A and B,
>>> we would rather the guest discover hypervisor A when running on A and
>>> hypervisor B when running on B. The priority encoding could be as simple as
>>> surfacing the native hypervisor signature earlier in the CPUID space.