Re: [PATCH v3 07/13] KVM: SVM: Enable SEV/SEV-ES functionality by default (when supported)

[Tom Lendacky]

On 1/22/21 2:21 PM, Sean Christopherson wrote:
> Enable the 'sev' and 'sev_es' module params by default instead of having
> them conditioned on CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT.  The extra
> Kconfig is pointless as KVM SEV/SEV-ES support is already controlled via
> CONFIG_KVM_AMD_SEV, and CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT has the
> unfortunate side effect of enabling all the SEV-ES _guest_ code due to
> it being dependent on CONFIG_AMD_MEM_ENCRYPT=y.
>
> Cc: Borislav Petkov <bp@xxxxxxx>
> Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
> Cc: Brijesh Singh <brijesh.singh@xxxxxxx>
> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>

Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>

> ---
>   arch/x86/kvm/svm/sev.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
> index 2b8ebe2f1caf..75a83e2a8a89 100644
> --- a/arch/x86/kvm/svm/sev.c
> +++ b/arch/x86/kvm/svm/sev.c
> @@ -29,11 +29,11 @@
>   
>   #ifdef CONFIG_KVM_AMD_SEV
>   /* enable/disable SEV support */
> -static bool sev_enabled = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);
> +static bool sev_enabled = true;
>   module_param_named(sev, sev_enabled, bool, 0444);
>   
>   /* enable/disable SEV-ES support */
> -static bool sev_es_enabled = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);
> +static bool sev_es_enabled = true;
>   module_param_named(sev_es, sev_es_enabled, bool, 0444);
>   #else
>   #define sev_enabled false