Re: [PATCH Part2 RFC v4 22/40] KVM: SVM: Add KVM_SNP_INIT command

From: Sean Christopherson
Date: Fri Jul 16 2021 - 15:33:41 EST


On Wed, Jul 07, 2021, Brijesh Singh wrote:
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 3fd9a7e9d90c..989a64aa1ae5 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1678,6 +1678,9 @@ enum sev_cmd_id {
> /* Guest Migration Extension */
> KVM_SEV_SEND_CANCEL,
>
> + /* SNP specific commands */
> + KVM_SEV_SNP_INIT = 256,

Is there any meaning behind '256'? If not, why skip a big chunk? I wouldn't be
concerned if it weren't for KVM_SEV_NR_MAX, whose existence arguably implies that
0-KVM_SEV_NR_MAX-1 are all valid SEV commands.

> +
> KVM_SEV_NR_MAX,
> };