Re: [PATCH 3/4] KVM: x86: hyper-v: Check if guest is allowed to use XMM registers for hypercall input

[Siddharth Chandrasekaran]

On Fri, Jul 30, 2021 at 02:26:24PM +0200, Vitaly Kuznetsov wrote:
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> 
> 
> TLFS states that "Availability of the XMM fast hypercall interface is
> indicated via the “Hypervisor Feature Identification” CPUID Leaf
> (0x40000003, see section 2.4.4) ... Any attempt to use this interface
> when the hypervisor does not indicate availability will result in a #UD
> fault."
> 
> Implement the check for 'strict' mode (KVM_CAP_HYPERV_ENFORCE_CPUID).
> 
> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>

Reviewed-by: Siddharth Chandrasekaran <sidcha@xxxxxxxxx>



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