[v11,25/35] KVM: SEV: Use a VMSA physical address variable for populating VMCB

Commit Message

Michael Roth Dec. 30, 2023, 5:23 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 | 3 +--
 arch/x86/kvm/svm/svm.c | 9 ++++++++-
 arch/x86/kvm/svm/svm.h | 1 +
 3 files changed, 10 insertions(+), 3 deletions(-)

Patch

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index ad1aea7f6266..996b5a668938 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3659,8 +3659,7 @@  static void sev_es_init_vmcb(struct vcpu_svm *svm)
 	 * the VMSA will be NULL if this vCPU is the destination for intrahost
 	 * migration, and will be copied later.
 	 */
-	if (svm->sev_es.vmsa)
-		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 4367da074612..da49e4981d75 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1459,9 +1459,16 @@  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 fb98d88d8124..4ef41f4d4ee6 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -202,6 +202,7 @@  struct vcpu_sev_es_state {
 	struct ghcb *ghcb;
 	u8 valid_bitmap[16];
 	struct kvm_host_map ghcb_map;
+	hpa_t vmsa_pa;
 	bool received_first_sipi;
 	unsigned int ap_reset_hold_type;