[RFC,v7,53/64] KVM: SVM: Use a VMSA physical address variable for populating VMCB

Commit Message

Michael Roth Dec. 14, 2022, 7:40 p.m. UTC

From: Tom Lendacky <[e-mail]>

In preparation to support SEV-SNP AP Creation, use a variable that holds
the VMSA physical address rather than converting the virtual address.
This will allow SEV-SNP AP Creation to set the new physical address that
will be used should the vCPU reset path be taken.

Signed-off-by: Tom Lendacky <[e-mail]>
Signed-off-by: Ashish Kalra <[e-mail]>
Signed-off-by: Michael Roth <[e-mail]>
---
 arch/x86/kvm/svm/sev.c | 5 ++---
 arch/x86/kvm/svm/svm.c | 9 ++++++++-
 arch/x86/kvm/svm/svm.h | 1 +
 3 files changed, 11 insertions(+), 4 deletions(-)

Patch

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 18efa70553c2..36c312143d12 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3845,10 +3845,9 @@  static void sev_es_init_vmcb(struct vcpu_svm *svm)
 
 	/*
 	 * An SEV-ES guest requires a VMSA area that is a separate from the
-	 * VMCB page. Do not include the encryption mask on the VMSA physical
-	 * address since hardware will access it using the guest key.
+	 * VMCB page.
 	 */
-	svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa);
+	svm->vmcb->control.vmsa_pa = svm->sev_es.vmsa_pa;
 
 	/* Can't intercept CR register access, HV can't modify CR registers */
 	svm_clr_intercept(svm, INTERCEPT_CR0_READ);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 43f04fc95a0a..e9317d27a01d 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1398,9 +1398,16 @@  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)
+	if (vmsa_page) {
 		svm->sev_es.vmsa = page_address(vmsa_page);
 
+		/*
+		 * Do not include the encryption mask on the VMSA physical
+		 * address since hardware will access it using the guest key.
+		 */
+		svm->sev_es.vmsa_pa = __pa(svm->sev_es.vmsa);
+	}
+
 	svm->guest_state_loaded = false;
 
 	return 0;
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 7c0f9d00950f..284902e22dce 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -204,6 +204,7 @@  struct svm_nested_state {
 struct vcpu_sev_es_state {
 	/* SEV-ES support */
 	struct sev_es_save_area *vmsa;
+	hpa_t vmsa_pa;
 	bool ghcb_in_use;
 	bool received_first_sipi;
 	unsigned int ap_reset_hold_type;