Re: [RFC PATCH v2 04/32] KVM: SVM: Add SEV feature definitions to KVM

From: Borislav Petkov
Date: Mon Mar 06 2017 - 19:54:39 EST


On Thu, Mar 02, 2017 at 10:12:48AM -0500, Brijesh Singh wrote:
> From: Tom Lendacky <thomas.lendacky@xxxxxxx>
>
> Define a new KVM CPU feature for Secure Encrypted Virtualization (SEV).
> The kernel will check for the presence of this feature to determine if
> it is running with SEV active.
>
> Define the SEV enable bit for the VMCB control structure. The hypervisor
> will use this bit to enable SEV in the guest.
>
> Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
> ---
> arch/x86/include/asm/svm.h | 1 +
> arch/x86/include/uapi/asm/kvm_para.h | 1 +
> 2 files changed, 2 insertions(+)
>
> diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
> index 2aca535..fba2a7b 100644
> --- a/arch/x86/include/asm/svm.h
> +++ b/arch/x86/include/asm/svm.h
> @@ -137,6 +137,7 @@ struct __attribute__ ((__packed__)) vmcb_control_area {
> #define SVM_VM_CR_SVM_DIS_MASK 0x0010ULL
>
> #define SVM_NESTED_CTL_NP_ENABLE BIT(0)
> +#define SVM_NESTED_CTL_SEV_ENABLE BIT(1)
>
> struct __attribute__ ((__packed__)) vmcb_seg {
> u16 selector;
> diff --git a/arch/x86/include/uapi/asm/kvm_para.h b/arch/x86/include/uapi/asm/kvm_para.h
> index 1421a65..bc2802f 100644
> --- a/arch/x86/include/uapi/asm/kvm_para.h
> +++ b/arch/x86/include/uapi/asm/kvm_para.h
> @@ -24,6 +24,7 @@
> #define KVM_FEATURE_STEAL_TIME 5
> #define KVM_FEATURE_PV_EOI 6
> #define KVM_FEATURE_PV_UNHALT 7
> +#define KVM_FEATURE_SEV 8

This looks like it needs documenting in Documentation/virtual/kvm/cpuid.txt

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Regards/Gruss,
Boris.

SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
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