summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--Documentation/virt/kvm/x86/amd-memory-encryption.rst28
-rw-r--r--arch/x86/include/uapi/asm/kvm.h17
-rw-r--r--arch/x86/kvm/svm/sev.c127
-rw-r--r--include/linux/psp-sev.h4
4 files changed, 175 insertions, 1 deletions
diff --git a/Documentation/virt/kvm/x86/amd-memory-encryption.rst b/Documentation/virt/kvm/x86/amd-memory-encryption.rst
index cc16a7426d18..1ddb6a86ce7f 100644
--- a/Documentation/virt/kvm/x86/amd-memory-encryption.rst
+++ b/Documentation/virt/kvm/x86/amd-memory-encryption.rst
@@ -544,6 +544,34 @@ where the allowed values for page_type are #define'd as::
See the SEV-SNP spec [snp-fw-abi]_ for further details on how each page type is
used/measured.
+20. KVM_SEV_SNP_LAUNCH_FINISH
+-----------------------------
+
+After completion of the SNP guest launch flow, the KVM_SEV_SNP_LAUNCH_FINISH
+command can be issued to make the guest ready for execution.
+
+Parameters (in): struct kvm_sev_snp_launch_finish
+
+Returns: 0 on success, -negative on error
+
+::
+
+ struct kvm_sev_snp_launch_finish {
+ __u64 id_block_uaddr;
+ __u64 id_auth_uaddr;
+ __u8 id_block_en;
+ __u8 auth_key_en;
+ __u8 vcek_disabled;
+ __u8 host_data[32];
+ __u8 pad0[3];
+ __u16 flags; /* Must be zero */
+ __u64 pad1[4];
+ };
+
+
+See SNP_LAUNCH_FINISH in the SEV-SNP specification [snp-fw-abi]_ for further
+details on the input parameters in ``struct kvm_sev_snp_launch_finish``.
+
Device attribute API
====================
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 5935dc8a7e02..988b5204d636 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -700,6 +700,7 @@ enum sev_cmd_id {
/* SNP-specific commands */
KVM_SEV_SNP_LAUNCH_START = 100,
KVM_SEV_SNP_LAUNCH_UPDATE,
+ KVM_SEV_SNP_LAUNCH_FINISH,
KVM_SEV_NR_MAX,
};
@@ -854,6 +855,22 @@ struct kvm_sev_snp_launch_update {
__u64 pad2[4];
};
+#define KVM_SEV_SNP_ID_BLOCK_SIZE 96
+#define KVM_SEV_SNP_ID_AUTH_SIZE 4096
+#define KVM_SEV_SNP_FINISH_DATA_SIZE 32
+
+struct kvm_sev_snp_launch_finish {
+ __u64 id_block_uaddr;
+ __u64 id_auth_uaddr;
+ __u8 id_block_en;
+ __u8 auth_key_en;
+ __u8 vcek_disabled;
+ __u8 host_data[KVM_SEV_SNP_FINISH_DATA_SIZE];
+ __u8 pad0[3];
+ __u16 flags;
+ __u64 pad1[4];
+};
+
#define KVM_X2APIC_API_USE_32BIT_IDS (1ULL << 0)
#define KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK (1ULL << 1)
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index c966f2224624..208bb8170d3f 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -75,6 +75,8 @@ static u64 sev_supported_vmsa_features;
SNP_POLICY_MASK_DEBUG | \
SNP_POLICY_MASK_SINGLE_SOCKET)
+#define INITIAL_VMSA_GPA 0xFFFFFFFFF000
+
static u8 sev_enc_bit;
static DECLARE_RWSEM(sev_deactivate_lock);
static DEFINE_MUTEX(sev_bitmap_lock);
@@ -2348,6 +2350,115 @@ out:
return ret;
}
+static int snp_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp)
+{
+ struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
+ struct sev_data_snp_launch_update data = {};
+ struct kvm_vcpu *vcpu;
+ unsigned long i;
+ int ret;
+
+ data.gctx_paddr = __psp_pa(sev->snp_context);
+ data.page_type = SNP_PAGE_TYPE_VMSA;
+
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ struct vcpu_svm *svm = to_svm(vcpu);
+ u64 pfn = __pa(svm->sev_es.vmsa) >> PAGE_SHIFT;
+
+ ret = sev_es_sync_vmsa(svm);
+ if (ret)
+ return ret;
+
+ /* Transition the VMSA page to a firmware state. */
+ ret = rmp_make_private(pfn, INITIAL_VMSA_GPA, PG_LEVEL_4K, sev->asid, true);
+ if (ret)
+ return ret;
+
+ /* Issue the SNP command to encrypt the VMSA */
+ data.address = __sme_pa(svm->sev_es.vmsa);
+ ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_SNP_LAUNCH_UPDATE,
+ &data, &argp->error);
+ if (ret) {
+ if (!snp_page_reclaim(pfn))
+ host_rmp_make_shared(pfn, PG_LEVEL_4K);
+
+ return ret;
+ }
+
+ svm->vcpu.arch.guest_state_protected = true;
+ }
+
+ return 0;
+}
+
+static int snp_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)
+{
+ struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
+ struct kvm_sev_snp_launch_finish params;
+ struct sev_data_snp_launch_finish *data;
+ void *id_block = NULL, *id_auth = NULL;
+ int ret;
+
+ if (!sev_snp_guest(kvm))
+ return -ENOTTY;
+
+ if (!sev->snp_context)
+ return -EINVAL;
+
+ if (copy_from_user(&params, u64_to_user_ptr(argp->data), sizeof(params)))
+ return -EFAULT;
+
+ if (params.flags)
+ return -EINVAL;
+
+ /* Measure all vCPUs using LAUNCH_UPDATE before finalizing the launch flow. */
+ ret = snp_launch_update_vmsa(kvm, argp);
+ if (ret)
+ return ret;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL_ACCOUNT);
+ if (!data)
+ return -ENOMEM;
+
+ if (params.id_block_en) {
+ id_block = psp_copy_user_blob(params.id_block_uaddr, KVM_SEV_SNP_ID_BLOCK_SIZE);
+ if (IS_ERR(id_block)) {
+ ret = PTR_ERR(id_block);
+ goto e_free;
+ }
+
+ data->id_block_en = 1;
+ data->id_block_paddr = __sme_pa(id_block);
+
+ id_auth = psp_copy_user_blob(params.id_auth_uaddr, KVM_SEV_SNP_ID_AUTH_SIZE);
+ if (IS_ERR(id_auth)) {
+ ret = PTR_ERR(id_auth);
+ goto e_free_id_block;
+ }
+
+ data->id_auth_paddr = __sme_pa(id_auth);
+
+ if (params.auth_key_en)
+ data->auth_key_en = 1;
+ }
+
+ data->vcek_disabled = params.vcek_disabled;
+
+ memcpy(data->host_data, params.host_data, KVM_SEV_SNP_FINISH_DATA_SIZE);
+ data->gctx_paddr = __psp_pa(sev->snp_context);
+ ret = sev_issue_cmd(kvm, SEV_CMD_SNP_LAUNCH_FINISH, data, &argp->error);
+
+ kfree(id_auth);
+
+e_free_id_block:
+ kfree(id_block);
+
+e_free:
+ kfree(data);
+
+ return ret;
+}
+
int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
struct kvm_sev_cmd sev_cmd;
@@ -2450,6 +2561,9 @@ int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
case KVM_SEV_SNP_LAUNCH_UPDATE:
r = snp_launch_update(kvm, &sev_cmd);
break;
+ case KVM_SEV_SNP_LAUNCH_FINISH:
+ r = snp_launch_finish(kvm, &sev_cmd);
+ break;
default:
r = -EINVAL;
goto out;
@@ -2940,11 +3054,24 @@ void sev_free_vcpu(struct kvm_vcpu *vcpu)
svm = to_svm(vcpu);
+ /*
+ * If it's an SNP guest, then the VMSA was marked in the RMP table as
+ * a guest-owned page. Transition the page to hypervisor state before
+ * releasing it back to the system.
+ */
+ if (sev_snp_guest(vcpu->kvm)) {
+ u64 pfn = __pa(svm->sev_es.vmsa) >> PAGE_SHIFT;
+
+ if (host_rmp_make_shared(pfn, PG_LEVEL_4K))
+ goto skip_vmsa_free;
+ }
+
if (vcpu->arch.guest_state_protected)
sev_flush_encrypted_page(vcpu, svm->sev_es.vmsa);
__free_page(virt_to_page(svm->sev_es.vmsa));
+skip_vmsa_free:
if (svm->sev_es.ghcb_sa_free)
kvfree(svm->sev_es.ghcb_sa);
}
diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h
index 3705c2044fc0..903ddfea8585 100644
--- a/include/linux/psp-sev.h
+++ b/include/linux/psp-sev.h
@@ -658,6 +658,7 @@ struct sev_data_snp_launch_update {
* @id_auth_paddr: system physical address of ID block authentication structure
* @id_block_en: indicates whether ID block is present
* @auth_key_en: indicates whether author key is present in authentication structure
+ * @vcek_disabled: indicates whether use of VCEK is allowed for attestation reports
* @rsvd: reserved
* @host_data: host-supplied data for guest, not interpreted by firmware
*/
@@ -667,7 +668,8 @@ struct sev_data_snp_launch_finish {
u64 id_auth_paddr;
u8 id_block_en:1;
u8 auth_key_en:1;
- u64 rsvd:62;
+ u8 vcek_disabled:1;
+ u64 rsvd:61;
u8 host_data[32];
} __packed;
generated by cgit v1.2.3 (git 2.46.0) at 2025-08-01 00:39:07 +0000