Re: [RFC Part2 PATCH v3 23/26] KVM: X86: Add memory encryption enabled ops

[Borislav Petkov]

On Mon, Jul 24, 2017 at 03:03:00PM -0500, Brijesh Singh wrote:
> Extend kvm_x86_ops to add memory_encyption_enabled() ops.

> It returns a
> boolean indicating whether memory encryption is enabled on the VCPU.

You don't need that sentence.

> 
> Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
> ---
>  arch/x86/include/asm/kvm_host.h | 1 +
>  arch/x86/kvm/svm.c              | 8 ++++++++
>  2 files changed, 9 insertions(+)
> 
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index a91aadf..a14d4dd 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -1073,6 +1073,7 @@ struct kvm_x86_ops {
>  					struct kvm_memory_encrypt_ram *ram);
>  	int (*memory_encryption_unregister_ram)(struct kvm *kvm,
>  					struct kvm_memory_encrypt_ram *ram);
> +	bool (*memory_encryption_enabled)(struct kvm_vcpu *vcpu);
>  };
>  
>  struct kvm_arch_async_pf {
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index cdb1cf3..0bbd050 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -6548,6 +6548,12 @@ static int mem_encrypt_unregister_ram(struct kvm *kvm,
>  	return 0;
>  }
>  
> +static bool mem_encrypt_enabled(struct kvm_vcpu *vcpu)
> +{
> +	return !!(to_svm(vcpu)->vmcb->control.nested_ctl &
> +					SVM_NESTED_CTL_SEV_ENABLE);

You don't need the !!

> +}
> +
>  static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
>  	.cpu_has_kvm_support = has_svm,
>  	.disabled_by_bios = is_disabled,
> @@ -6664,6 +6670,8 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
>  	.memory_encryption_op = svm_memory_encryption_op,
>  	.memory_encryption_register_ram = mem_encrypt_register_ram,
>  	.memory_encryption_unregister_ram = mem_encrypt_unregister_ram,
> +	.memory_encryption_enabled = mem_encrypt_enabled,
> +

mem_enc_enabled looks better to me.

-- 
Regards/Gruss,
    Boris.

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