On 5/6/21 3:25 PM, Peter Gonda wrote:
> On Fri, Apr 30, 2021 at 6:44 AM Brijesh Singh <brijesh.singh@xxxxxxx> wrote:
>> The KVM_SNP_INIT command is used by the hypervisor to initialize the
>> SEV-SNP platform context. In a typical workflow, this command should be the
>> first command issued. When creating SEV-SNP guest, the VMM must use this
>> command instead of the KVM_SEV_INIT or KVM_SEV_ES_INIT.
>>
>> Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
>> ---
>> arch/x86/kvm/svm/sev.c | 18 ++++++++++++++++--
>> include/uapi/linux/kvm.h | 3 +++
>> 2 files changed, 19 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
>> index 200d227f9232..ea74dd9e03d3 100644
>> --- a/arch/x86/kvm/svm/sev.c
>> +++ b/arch/x86/kvm/svm/sev.c
>> @@ -230,8 +230,9 @@ static void sev_unbind_asid(struct kvm *kvm, unsigned int handle)
>>
>> static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp)
>> {
>> + bool es_active = (argp->id == KVM_SEV_ES_INIT || argp->id == KVM_SEV_SNP_INIT);
>> struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
>> - bool es_active = argp->id == KVM_SEV_ES_INIT;
>> + bool snp_active = argp->id == KVM_SEV_SNP_INIT;
>> int asid, ret;
>>
>> if (kvm->created_vcpus)
>> @@ -242,12 +243,16 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp)
>> return ret;
>>
>> sev->es_active = es_active;
>> + sev->snp_active = snp_active;
>> asid = sev_asid_new(sev);
>> if (asid < 0)
>> goto e_no_asid;
>> sev->asid = asid;
>>
>> - ret = sev_platform_init(&argp->error);
>> + if (snp_active)
>> + ret = sev_snp_init(&argp->error);
>> + else
>> + ret = sev_platform_init(&argp->error);
>> if (ret)
>> goto e_free;
>>
>> @@ -583,6 +588,9 @@ static int sev_es_sync_vmsa(struct vcpu_svm *svm)
>> save->pkru = svm->vcpu.arch.pkru;
>> save->xss = svm->vcpu.arch.ia32_xss;
>>
>> + if (sev_snp_guest(svm->vcpu.kvm))
>> + save->sev_features |= SVM_SEV_FEATURES_SNP_ACTIVE;
>> +
>> /*
>> * SEV-ES will use a VMSA that is pointed to by the VMCB, not
>> * the traditional VMSA that is part of the VMCB. Copy the
>> @@ -1525,6 +1533,12 @@ int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
>> }
>>
>> switch (sev_cmd.id) {
>> + case KVM_SEV_SNP_INIT:
>> + if (!sev_snp_enabled) {
>> + r = -ENOTTY;
>> + goto out;
>> + }
>> + fallthrough;
>> case KVM_SEV_ES_INIT:
>> if (!sev_es_enabled) {
>> r = -ENOTTY;
>> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
>> index 3fd9a7e9d90c..aaa2d62f09b5 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,
>> +
> Do you want to reserve some more enum values for SEV in case
> additional functionality is added, or is this very unlikely?
Good idea, I will reserve some enum.
