1 files changed, 146 insertions, 83 deletions

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 1aa0f07d3a63..459c3b791fd4 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -561,6 +561,8 @@ static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp)
 	if (copy_from_user(&params, u64_to_user_ptr(argp->data), sizeof(params)))
 		return -EFAULT;
 
+	sev->policy = params.policy;
+
 	memset(&start, 0, sizeof(start));
 
 	dh_blob = NULL;
@@ -1593,11 +1595,11 @@ static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
 
 	/* allocate memory for header and transport buffer */
 	ret = -ENOMEM;
-	hdr = kzalloc(params.hdr_len, GFP_KERNEL_ACCOUNT);
+	hdr = kzalloc(params.hdr_len, GFP_KERNEL);
 	if (!hdr)
 		goto e_unpin;
 
-	trans_data = kzalloc(params.trans_len, GFP_KERNEL_ACCOUNT);
+	trans_data = kzalloc(params.trans_len, GFP_KERNEL);
 	if (!trans_data)
 		goto e_free_hdr;
 
@@ -1883,70 +1885,6 @@ static void sev_unlock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm)
 	atomic_set_release(&src_sev->migration_in_progress, 0);
 }
 
-/* vCPU mutex subclasses.  */
-enum sev_migration_role {
-	SEV_MIGRATION_SOURCE = 0,
-	SEV_MIGRATION_TARGET,
-	SEV_NR_MIGRATION_ROLES,
-};
-
-static int sev_lock_vcpus_for_migration(struct kvm *kvm,
-					enum sev_migration_role role)
-{
-	struct kvm_vcpu *vcpu;
-	unsigned long i, j;
-
-	kvm_for_each_vcpu(i, vcpu, kvm) {
-		if (mutex_lock_killable_nested(&vcpu->mutex, role))
-			goto out_unlock;
-
-#ifdef CONFIG_PROVE_LOCKING
-		if (!i)
-			/*
-			 * Reset the role to one that avoids colliding with
-			 * the role used for the first vcpu mutex.
-			 */
-			role = SEV_NR_MIGRATION_ROLES;
-		else
-			mutex_release(&vcpu->mutex.dep_map, _THIS_IP_);
-#endif
-	}
-
-	return 0;
-
-out_unlock:
-
-	kvm_for_each_vcpu(j, vcpu, kvm) {
-		if (i == j)
-			break;
-
-#ifdef CONFIG_PROVE_LOCKING
-		if (j)
-			mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_);
-#endif
-
-		mutex_unlock(&vcpu->mutex);
-	}
-	return -EINTR;
-}
-
-static void sev_unlock_vcpus_for_migration(struct kvm *kvm)
-{
-	struct kvm_vcpu *vcpu;
-	unsigned long i;
-	bool first = true;
-
-	kvm_for_each_vcpu(i, vcpu, kvm) {
-		if (first)
-			first = false;
-		else
-			mutex_acquire(&vcpu->mutex.dep_map,
-				      SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_);
-
-		mutex_unlock(&vcpu->mutex);
-	}
-}
-
 static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm)
 {
 	struct kvm_sev_info *dst = to_kvm_sev_info(dst_kvm);
@@ -2084,10 +2022,10 @@ int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd)
 		charged = true;
 	}
 
-	ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE);
+	ret = kvm_lock_all_vcpus(kvm);
 	if (ret)
 		goto out_dst_cgroup;
-	ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET);
+	ret = kvm_lock_all_vcpus(source_kvm);
 	if (ret)
 		goto out_dst_vcpu;
 
@@ -2101,9 +2039,9 @@ int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd)
 	ret = 0;
 
 out_source_vcpu:
-	sev_unlock_vcpus_for_migration(source_kvm);
+	kvm_unlock_all_vcpus(source_kvm);
 out_dst_vcpu:
-	sev_unlock_vcpus_for_migration(kvm);
+	kvm_unlock_all_vcpus(kvm);
 out_dst_cgroup:
 	/* Operates on the source on success, on the destination on failure.  */
 	if (charged)
@@ -2200,6 +2138,8 @@ static int snp_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp)
 	if (params.policy & SNP_POLICY_MASK_SINGLE_SOCKET)
 		return -EINVAL;
 
+	sev->policy = params.policy;
+
 	sev->snp_context = snp_context_create(kvm, argp);
 	if (!sev->snp_context)
 		return -ENOTTY;
@@ -2931,6 +2871,33 @@ void __init sev_set_cpu_caps(void)
 	}
 }
 
+static bool is_sev_snp_initialized(void)
+{
+	struct sev_user_data_snp_status *status;
+	struct sev_data_snp_addr buf;
+	bool initialized = false;
+	int ret, error = 0;
+
+	status = snp_alloc_firmware_page(GFP_KERNEL | __GFP_ZERO);
+	if (!status)
+		return false;
+
+	buf.address = __psp_pa(status);
+	ret = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &error);
+	if (ret) {
+		pr_err("SEV: SNP_PLATFORM_STATUS failed ret=%d, fw_error=%d (%#x)\n",
+		       ret, error, error);
+		goto out;
+	}
+
+	initialized = !!status->state;
+
+out:
+	snp_free_firmware_page(status);
+
+	return initialized;
+}
+
 void __init sev_hardware_setup(void)
 {
 	unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count;
@@ -3035,6 +3002,14 @@ void __init sev_hardware_setup(void)
 	sev_snp_supported = sev_snp_enabled && cc_platform_has(CC_ATTR_HOST_SEV_SNP);
 
 out:
+	if (sev_enabled) {
+		init_args.probe = true;
+		if (sev_platform_init(&init_args))
+			sev_supported = sev_es_supported = sev_snp_supported = false;
+		else if (sev_snp_supported)
+			sev_snp_supported = is_sev_snp_initialized();
+	}
+
 	if (boot_cpu_has(X86_FEATURE_SEV))
 		pr_info("SEV %s (ASIDs %u - %u)\n",
 			sev_supported ? min_sev_asid <= max_sev_asid ? "enabled" :
@@ -3061,15 +3036,6 @@ out:
 	sev_supported_vmsa_features = 0;
 	if (sev_es_debug_swap_enabled)
 		sev_supported_vmsa_features |= SVM_SEV_FEAT_DEBUG_SWAP;
-
-	if (!sev_enabled)
-		return;
-
-	/*
-	 * Do both SNP and SEV initialization at KVM module load.
-	 */
-	init_args.probe = true;
-	sev_platform_init(&init_args);
 }
 
 void sev_hardware_unsetup(void)
@@ -4007,10 +3973,8 @@ static int sev_snp_ap_creation(struct vcpu_svm *svm)
 	 * Unless Creation is deferred until INIT, signal the vCPU to update
 	 * its state.
 	 */
-	if (request != SVM_VMGEXIT_AP_CREATE_ON_INIT) {
-		kvm_make_request(KVM_REQ_UPDATE_PROTECTED_GUEST_STATE, target_vcpu);
-		kvm_vcpu_kick(target_vcpu);
-	}
+	if (request != SVM_VMGEXIT_AP_CREATE_ON_INIT)
+		kvm_make_request_and_kick(KVM_REQ_UPDATE_PROTECTED_GUEST_STATE, target_vcpu);
 
 	return 0;
 }
@@ -4468,6 +4432,7 @@ void sev_vcpu_after_set_cpuid(struct vcpu_svm *svm)
 
 static void sev_es_init_vmcb(struct vcpu_svm *svm)
 {
+	struct kvm_sev_info *sev = to_kvm_sev_info(svm->vcpu.kvm);
 	struct vmcb *vmcb = svm->vmcb01.ptr;
 	struct kvm_vcpu *vcpu = &svm->vcpu;
 
@@ -4483,6 +4448,10 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm)
 	if (svm->sev_es.vmsa && !svm->sev_es.snp_has_guest_vmsa)
 		svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa);
 
+	if (cpu_feature_enabled(X86_FEATURE_ALLOWED_SEV_FEATURES))
+		svm->vmcb->control.allowed_sev_features = sev->vmsa_features |
+							  VMCB_ALLOWED_SEV_FEATURES_VALID;
+
 	/* Can't intercept CR register access, HV can't modify CR registers */
 	svm_clr_intercept(svm, INTERCEPT_CR0_READ);
 	svm_clr_intercept(svm, INTERCEPT_CR4_READ);
@@ -4943,3 +4912,97 @@ int sev_private_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn)
 
 	return level;
 }
+
+struct vmcb_save_area *sev_decrypt_vmsa(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_svm *svm = to_svm(vcpu);
+	struct vmcb_save_area *vmsa;
+	struct kvm_sev_info *sev;
+	int error = 0;
+	int ret;
+
+	if (!sev_es_guest(vcpu->kvm))
+		return NULL;
+
+	/*
+	 * If the VMSA has not yet been encrypted, return a pointer to the
+	 * current un-encrypted VMSA.
+	 */
+	if (!vcpu->arch.guest_state_protected)
+		return (struct vmcb_save_area *)svm->sev_es.vmsa;
+
+	sev = to_kvm_sev_info(vcpu->kvm);
+
+	/* Check if the SEV policy allows debugging */
+	if (sev_snp_guest(vcpu->kvm)) {
+		if (!(sev->policy & SNP_POLICY_DEBUG))
+			return NULL;
+	} else {
+		if (sev->policy & SEV_POLICY_NODBG)
+			return NULL;
+	}
+
+	if (sev_snp_guest(vcpu->kvm)) {
+		struct sev_data_snp_dbg dbg = {0};
+
+		vmsa = snp_alloc_firmware_page(__GFP_ZERO);
+		if (!vmsa)
+			return NULL;
+
+		dbg.gctx_paddr = __psp_pa(sev->snp_context);
+		dbg.src_addr = svm->vmcb->control.vmsa_pa;
+		dbg.dst_addr = __psp_pa(vmsa);
+
+		ret = sev_do_cmd(SEV_CMD_SNP_DBG_DECRYPT, &dbg, &error);
+
+		/*
+		 * Return the target page to a hypervisor page no matter what.
+		 * If this fails, the page can't be used, so leak it and don't
+		 * try to use it.
+		 */
+		if (snp_page_reclaim(vcpu->kvm, PHYS_PFN(__pa(vmsa))))
+			return NULL;
+
+		if (ret) {
+			pr_err("SEV: SNP_DBG_DECRYPT failed ret=%d, fw_error=%d (%#x)\n",
+			       ret, error, error);
+			free_page((unsigned long)vmsa);
+
+			return NULL;
+		}
+	} else {
+		struct sev_data_dbg dbg = {0};
+		struct page *vmsa_page;
+
+		vmsa_page = alloc_page(GFP_KERNEL);
+		if (!vmsa_page)
+			return NULL;
+
+		vmsa = page_address(vmsa_page);
+
+		dbg.handle = sev->handle;
+		dbg.src_addr = svm->vmcb->control.vmsa_pa;
+		dbg.dst_addr = __psp_pa(vmsa);
+		dbg.len = PAGE_SIZE;
+
+		ret = sev_do_cmd(SEV_CMD_DBG_DECRYPT, &dbg, &error);
+		if (ret) {
+			pr_err("SEV: SEV_CMD_DBG_DECRYPT failed ret=%d, fw_error=%d (0x%x)\n",
+			       ret, error, error);
+			__free_page(vmsa_page);
+
+			return NULL;
+		}
+	}
+
+	return vmsa;
+}
+
+void sev_free_decrypted_vmsa(struct kvm_vcpu *vcpu, struct vmcb_save_area *vmsa)
+{
+	/* If the VMSA has not yet been encrypted, nothing was allocated */
+	if (!vcpu->arch.guest_state_protected || !vmsa)
+		return;
+
+	free_page((unsigned long)vmsa);
+}