[PATCH 03/15] KVM: SVM: Always clear available of VCPU_EXREG_PDPTR in svm_vcpu_run()

From: Lai Jiangshan
Date: Mon Nov 08 2021 - 07:44:31 EST


From: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>

Make it the same logic to handle the availability of VCPU_EXREG_PDPTR
as VMX and also remove a branch in svm_vcpu_run().

Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>
---
arch/x86/kvm/svm/svm.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 88a730ad47a1..3e7043173668 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1583,10 +1583,16 @@ static void svm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)

static void svm_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg)
{
+ kvm_register_mark_available(vcpu, reg);
+
switch (reg) {
case VCPU_EXREG_PDPTR:
- BUG_ON(!npt_enabled);
- load_pdptrs(vcpu, vcpu->arch.walk_mmu, kvm_read_cr3(vcpu));
+ /*
+ * When !npt_enabled, mmu->pdptrs[] is already available since
+ * it is always updated per SDM when moving to CRs.
+ */
+ if (npt_enabled)
+ load_pdptrs(vcpu, vcpu->arch.walk_mmu, kvm_read_cr3(vcpu));
break;
default:
KVM_BUG_ON(1, vcpu->kvm);
@@ -3964,8 +3970,7 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
svm->vmcb->control.tlb_ctl = TLB_CONTROL_DO_NOTHING;
vmcb_mark_all_clean(svm->vmcb);

- if (npt_enabled)
- kvm_register_clear_available(vcpu, VCPU_EXREG_PDPTR);
+ kvm_register_clear_available(vcpu, VCPU_EXREG_PDPTR);

/*
* We need to handle MC intercepts here before the vcpu has a chance to
--
2.19.1.6.gb485710b