[PATCH v3 1/9] KVM: nSVM: split kvm_init_shadow_npt_mmu() from kvm_init_shadow_mmu()

From: Vitaly Kuznetsov
Date: Thu Jul 09 2020 - 10:54:15 EST


As a preparatory change for moving kvm_mmu_new_pgd() from
nested_prepare_vmcb_save() to nested_svm_init_mmu_context() split
kvm_init_shadow_npt_mmu() from kvm_init_shadow_mmu(). This also makes
the code look more like nVMX (kvm_init_shadow_ept_mmu()).

No functional change intended.

Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
---
arch/x86/kvm/mmu.h | 3 ++-
arch/x86/kvm/mmu/mmu.c | 31 ++++++++++++++++++++++++-------
arch/x86/kvm/svm/nested.c | 3 ++-
3 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 444bb9c54548..94378ef1df54 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -57,7 +57,8 @@ void
reset_shadow_zero_bits_mask(struct kvm_vcpu *vcpu, struct kvm_mmu *context);

void kvm_init_mmu(struct kvm_vcpu *vcpu, bool reset_roots);
-void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer);
+void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer,
+ gpa_t nested_cr3);
void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly,
bool accessed_dirty, gpa_t new_eptp);
bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 2da46b4e11b5..93f18e5fa8b5 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4952,14 +4952,10 @@ kvm_calc_shadow_mmu_root_page_role(struct kvm_vcpu *vcpu, bool base_only)
return role;
}

-void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer)
+static void shadow_mmu_init_context(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4,
+ u32 efer, union kvm_mmu_role new_role)
{
struct kvm_mmu *context = vcpu->arch.mmu;
- union kvm_mmu_role new_role =
- kvm_calc_shadow_mmu_root_page_role(vcpu, false);
-
- if (new_role.as_u64 == context->mmu_role.as_u64)
- return;

if (!(cr0 & X86_CR0_PG))
nonpaging_init_context(vcpu, context);
@@ -4973,7 +4969,28 @@ void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer)
context->mmu_role.as_u64 = new_role.as_u64;
reset_shadow_zero_bits_mask(vcpu, context);
}
-EXPORT_SYMBOL_GPL(kvm_init_shadow_mmu);
+
+static void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer)
+{
+ struct kvm_mmu *context = vcpu->arch.mmu;
+ union kvm_mmu_role new_role =
+ kvm_calc_shadow_mmu_root_page_role(vcpu, false);
+
+ if (new_role.as_u64 != context->mmu_role.as_u64)
+ shadow_mmu_init_context(vcpu, cr0, cr4, efer, new_role);
+}
+
+void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer,
+ gpa_t nested_cr3)
+{
+ struct kvm_mmu *context = vcpu->arch.mmu;
+ union kvm_mmu_role new_role =
+ kvm_calc_shadow_mmu_root_page_role(vcpu, false);
+
+ if (new_role.as_u64 != context->mmu_role.as_u64)
+ shadow_mmu_init_context(vcpu, cr0, cr4, efer, new_role);
+}
+EXPORT_SYMBOL_GPL(kvm_init_shadow_npt_mmu);

static union kvm_mmu_role
kvm_calc_shadow_ept_root_page_role(struct kvm_vcpu *vcpu, bool accessed_dirty,
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 6bceafb19108..e424bce13e6c 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -87,7 +87,8 @@ static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu)
WARN_ON(mmu_is_nested(vcpu));

vcpu->arch.mmu = &vcpu->arch.guest_mmu;
- kvm_init_shadow_mmu(vcpu, X86_CR0_PG, hsave->save.cr4, hsave->save.efer);
+ kvm_init_shadow_npt_mmu(vcpu, X86_CR0_PG, hsave->save.cr4, hsave->save.efer,
+ svm->nested.ctl.nested_cr3);
vcpu->arch.mmu->get_guest_pgd = nested_svm_get_tdp_cr3;
vcpu->arch.mmu->get_pdptr = nested_svm_get_tdp_pdptr;
vcpu->arch.mmu->inject_page_fault = nested_svm_inject_npf_exit;
--
2.25.4