KVM: MMU: Introduce init_kvm_nested_mmu()
This patch introduces the init_kvm_nested_mmu() function
which is used to re-initialize the nested mmu when the l2
guest changes its paging mode.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 1e215e8..a26f13b 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2784,11 +2784,46 @@
return r;
}
+static int init_kvm_nested_mmu(struct kvm_vcpu *vcpu)
+{
+ struct kvm_mmu *g_context = &vcpu->arch.nested_mmu;
+
+ g_context->get_cr3 = get_cr3;
+ g_context->inject_page_fault = kvm_inject_page_fault;
+
+ /*
+ * Note that arch.mmu.gva_to_gpa translates l2_gva to l1_gpa. The
+ * translation of l2_gpa to l1_gpa addresses is done using the
+ * arch.nested_mmu.gva_to_gpa function. Basically the gva_to_gpa
+ * functions between mmu and nested_mmu are swapped.
+ */
+ if (!is_paging(vcpu)) {
+ g_context->root_level = 0;
+ g_context->gva_to_gpa = nonpaging_gva_to_gpa_nested;
+ } else if (is_long_mode(vcpu)) {
+ reset_rsvds_bits_mask(vcpu, g_context, PT64_ROOT_LEVEL);
+ g_context->root_level = PT64_ROOT_LEVEL;
+ g_context->gva_to_gpa = paging64_gva_to_gpa_nested;
+ } else if (is_pae(vcpu)) {
+ reset_rsvds_bits_mask(vcpu, g_context, PT32E_ROOT_LEVEL);
+ g_context->root_level = PT32E_ROOT_LEVEL;
+ g_context->gva_to_gpa = paging64_gva_to_gpa_nested;
+ } else {
+ reset_rsvds_bits_mask(vcpu, g_context, PT32_ROOT_LEVEL);
+ g_context->root_level = PT32_ROOT_LEVEL;
+ g_context->gva_to_gpa = paging32_gva_to_gpa_nested;
+ }
+
+ return 0;
+}
+
static int init_kvm_mmu(struct kvm_vcpu *vcpu)
{
vcpu->arch.update_pte.pfn = bad_pfn;
- if (tdp_enabled)
+ if (mmu_is_nested(vcpu))
+ return init_kvm_nested_mmu(vcpu);
+ else if (tdp_enabled)
return init_kvm_tdp_mmu(vcpu);
else
return init_kvm_softmmu(vcpu);
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 7086ca8..513abbb 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -47,6 +47,7 @@
#define PFERR_USER_MASK (1U << 2)
#define PFERR_RSVD_MASK (1U << 3)
#define PFERR_FETCH_MASK (1U << 4)
+#define PFERR_NESTED_MASK (1U << 31)
int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]);
int kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, struct kvm_mmu *context);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 46843ed..e4c76bf 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3489,6 +3489,22 @@
return gpa;
}
+static gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access)
+{
+ gpa_t t_gpa;
+ u32 error;
+
+ BUG_ON(!mmu_is_nested(vcpu));
+
+ /* NPT walks are always user-walks */
+ access |= PFERR_USER_MASK;
+ t_gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gpa, access, &error);
+ if (t_gpa == UNMAPPED_GVA)
+ vcpu->arch.fault.error_code |= PFERR_NESTED_MASK;
+
+ return t_gpa;
+}
+
gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva, u32 *error)
{
u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0;
@@ -5704,6 +5720,7 @@
vcpu->arch.walk_mmu = &vcpu->arch.mmu;
vcpu->arch.mmu.root_hpa = INVALID_PAGE;
vcpu->arch.mmu.translate_gpa = translate_gpa;
+ vcpu->arch.nested_mmu.translate_gpa = translate_nested_gpa;
if (!irqchip_in_kernel(kvm) || kvm_vcpu_is_bsp(vcpu))
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
else