Re: [PATCH 4/4] sev/i386: Enable an SEV-ES guest based on SEV policy

[Connor Kuehl]

On 8/25/20 2:05 PM, Tom Lendacky wrote:
> From: Tom Lendacky <thomas.lendacky@amd.com>
>
> Update the sev_es_enabled() function return value to be based on the SEV
> policy that has been specified. SEV-ES is enabled if SEV is enabled and
> the SEV-ES policy bit is set in the policy object.
>
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
> ---
>   target/i386/sev.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/target/i386/sev.c b/target/i386/sev.c
> index 5146b788fb..153c2cba2c 100644
> --- a/target/i386/sev.c
> +++ b/target/i386/sev.c
> @@ -70,6 +70,8 @@ struct SevGuestState {
>   #define DEFAULT_GUEST_POLICY    0x1 /* disable debug */
>   #define DEFAULT_SEV_DEVICE      "/dev/sev"
>   
> +#define GUEST_POLICY_SEV_ES_BIT (1 << 2)
> +
>   /* SEV Information Block GUID = 00f771de-1a7e-4fcb-890e-68c77e2fb44e */
>   #define SEV_INFO_BLOCK_GUID 
> "\xde\x71\xf7\x00\x7e\x1a\xcb\x4f\x89\x0e\x68\xc7\x7e\x2f\xb4\x4e"
>   
> @@ -374,7 +376,7 @@ sev_enabled(void)
>   bool
>   sev_es_enabled(void)
>   {
> -    return false;
> +    return (sev_enabled() && (sev_guest->policy & GUEST_POLICY_SEV_ES_BIT));

checkpatch wants these outer parentheses removed :-)

>   }
>   
>   uint64_t