Re: [RFCv2 02/13] x86/kvm: Introduce KVM memory protection feature

[Borislav Petkov]

On Fri, Apr 16, 2021 at 06:40:55PM +0300, Kirill A. Shutemov wrote:
> Provide basic helpers, KVM_FEATURE, CPUID flag and a hypercall.
> 
> Host side doesn't provide the feature yet, so it is a dead code for now.
> 
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> ---
>  arch/x86/include/asm/cpufeatures.h   |  1 +
>  arch/x86/include/asm/kvm_para.h      |  5 +++++
>  arch/x86/include/uapi/asm/kvm_para.h |  3 ++-
>  arch/x86/kernel/kvm.c                | 17 +++++++++++++++++
>  include/uapi/linux/kvm_para.h        |  3 ++-
>  5 files changed, 27 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
> index 84b887825f12..d8f3d2619913 100644
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@ -238,6 +238,7 @@
>  #define X86_FEATURE_VMW_VMMCALL		( 8*32+19) /* "" VMware prefers VMMCALL hypercall instruction */
>  #define X86_FEATURE_SEV_ES		( 8*32+20) /* AMD Secure Encrypted Virtualization - Encrypted State */
>  #define X86_FEATURE_VM_PAGE_FLUSH	( 8*32+21) /* "" VM Page Flush MSR is supported */
> +#define X86_FEATURE_KVM_MEM_PROTECTED	( 8*32+22) /* "" KVM memory protection extension */

That feature bit is still unused.

-- 
Regards/Gruss,
    Boris.

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