Commit 34bd82aa authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: SVM: Move SEV-ES VMSA allocation to a dedicated sev_vcpu_create() helper 



Add a dedicated sev_vcpu_create() helper to allocate the VMSA page for
SEV-ES+ vCPUs, and to allow for consolidating a variety of related SEV+
code in the near future.

No functional change intended.

Reviewed-by: default avatarNikunj A Dadhania <nikunj@amd.com>
Link: https://lore.kernel.org/r/20250819234833.3080255-5-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 7b59c73f

arch/x86/kvm/svm/sev.c

+20 −0
Original line number Diff line number Diff line
@@ -4561,6 +4561,26 @@ void sev_init_vmcb(struct vcpu_svm *svm) 
		sev_es_init_vmcb(svm);

}



int sev_vcpu_create(struct kvm_vcpu *vcpu)

{

	struct vcpu_svm *svm = to_svm(vcpu);

	struct page *vmsa_page;



	if (!sev_es_guest(vcpu->kvm))

		return 0;



	/*

	 * SEV-ES guests require a separate (from the VMCB) VMSA page used to

	 * contain the encrypted register state of the guest.

	 */

	vmsa_page = snp_safe_alloc_page();

	if (!vmsa_page)

		return -ENOMEM;



	svm->sev_es.vmsa = page_address(vmsa_page);

	return 0;

}



void sev_es_vcpu_reset(struct vcpu_svm *svm)

{

	struct kvm_vcpu *vcpu = &svm->vcpu;

arch/x86/kvm/svm/svm.c

+7 −18
Original line number Diff line number Diff line
@@ -1275,7 +1275,6 @@ static int svm_vcpu_create(struct kvm_vcpu *vcpu) 
{

	struct vcpu_svm *svm;

	struct page *vmcb01_page;

	struct page *vmsa_page = NULL;

	int err;



	BUILD_BUG_ON(offsetof(struct vcpu_svm, vcpu) != 0);
@@ -1286,24 +1285,18 @@ static int svm_vcpu_create(struct kvm_vcpu *vcpu) 
	if (!vmcb01_page)

		goto out;



	if (sev_es_guest(vcpu->kvm)) {

		/*

		 * SEV-ES guests require a separate VMSA page used to contain

		 * the encrypted register state of the guest.

		 */

		vmsa_page = snp_safe_alloc_page();

		if (!vmsa_page)

	err = sev_vcpu_create(vcpu);

	if (err)

		goto error_free_vmcb_page;

	}



	err = avic_init_vcpu(svm);

	if (err)

		goto error_free_vmsa_page;

		goto error_free_sev;



	svm->msrpm = svm_vcpu_alloc_msrpm();

	if (!svm->msrpm) {

		err = -ENOMEM;

		goto error_free_vmsa_page;

		goto error_free_sev;

	}



	svm->x2avic_msrs_intercepted = true;
@@ -1312,16 +1305,12 @@ static int svm_vcpu_create(struct kvm_vcpu *vcpu) 
	svm->vmcb01.pa = __sme_set(page_to_pfn(vmcb01_page) << PAGE_SHIFT);

	svm_switch_vmcb(svm, &svm->vmcb01);



	if (vmsa_page)

		svm->sev_es.vmsa = page_address(vmsa_page);



	svm->guest_state_loaded = false;



	return 0;



error_free_vmsa_page:

	if (vmsa_page)

		__free_page(vmsa_page);

error_free_sev:

	sev_free_vcpu(vcpu);

error_free_vmcb_page:

	__free_page(vmcb01_page);

out:

arch/x86/kvm/svm/svm.h

+2 −0
Original line number Diff line number Diff line
@@ -854,6 +854,7 @@ static inline struct page *snp_safe_alloc_page(void) 
	return snp_safe_alloc_page_node(numa_node_id(), GFP_KERNEL_ACCOUNT);

}



int sev_vcpu_create(struct kvm_vcpu *vcpu);

void sev_free_vcpu(struct kvm_vcpu *vcpu);

void sev_vm_destroy(struct kvm *kvm);

void __init sev_set_cpu_caps(void);
@@ -880,6 +881,7 @@ static inline struct page *snp_safe_alloc_page(void) 
	return snp_safe_alloc_page_node(numa_node_id(), GFP_KERNEL_ACCOUNT);

}



static inline int sev_vcpu_create(struct kvm_vcpu *vcpu) { return 0; }

static inline void sev_free_vcpu(struct kvm_vcpu *vcpu) {}

static inline void sev_vm_destroy(struct kvm *kvm) {}

static inline void __init sev_set_cpu_caps(void) {}