From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: Does KVM support Intel FlexMigration feature?
Date: Tue, 03 Dec 2013 13:55:11 +0100
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To: Xuekun Hu <xuekun.hu@gmail.com>
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Il 03/12/2013 06:50, Xuekun Hu ha scritto:
> Hi, All
> 
> Does KVM support Intel FlexMigration feature? If yes, is there a doc
> to describe how to do use it (set cpu features mask)?
> Many thanks.

KVM uses Intel's virtualization extensions (VT-x) for CPUID exits, and
not the masking/faulting MSRs.  CPUID support is controlled by userspace
(i.e. outside KVM), using the KVM_GET_SUPPORTED_CPUID and KVM_SET_CPUID2
ioctl.

The ioctls are documented in Documentation/virtual/kvm/api.txt.

The KVM_SET_CPUID2 ioctl is not documented but it is the same as
KVM_SET_CPUID, except that is uses "struct kvm_cpuid2" instead of
"struct kvm_cpuid".

Paolo