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

Borislav Petkov
2021-04-16T16:10:42Z

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@linux.intel.com>
> ---
> 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.