When emulating INVVPID for L1, free only L2+ roots, using the guest_mode
tag in the MMU role to identify L2+ roots. From L1's perspective, its
own TLB entries use VPID=0, and INVVPID is not requied to invalidate such
entries. Per Intel's SDM, INVVPID _may_ invalidate entries with VPID=0,
but it is not required to do so.
Cc: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/mmu/mmu.c | 27 +++++++++++++++++++++++++++
arch/x86/kvm/vmx/nested.c | 7 +++----
3 files changed, 31 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index c05448d3beff..05c5ca047c53 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1650,6 +1650,7 @@ int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn);
void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu);
void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
ulong roots_to_free);
+void kvm_mmu_free_guest_mode_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu);
gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access,
struct x86_exception *exception);
gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva,
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index a832e0fedf32..f987f2ea4a01 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3180,6 +3180,33 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
}
EXPORT_SYMBOL_GPL(kvm_mmu_free_roots);
+void kvm_mmu_free_guest_mode_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
+{
+ unsigned long roots_to_free = 0;
+ hpa_t root_hpa;
+ int i;
+
+ /*
+ * This should not be called while L2 is active, L2 can't invalidate
+ * _only_ its own roots, e.g. INVVPID unconditionally exits.
+ */
+ WARN_ON_ONCE(mmu->mmu_role.base.guest_mode);
+
+ for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
+ root_hpa = mmu->prev_roots[i].hpa;
+ if (!VALID_PAGE(root_hpa))
+ continue;
+
+ if (!to_shadow_page(root_hpa) ||
+ to_shadow_page(root_hpa)->role.guest_mode)
+ roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
+ }
+
+ kvm_mmu_free_roots(vcpu, mmu, roots_to_free);
+}
+EXPORT_SYMBOL_GPL(kvm_mmu_free_guest_mode_roots);
+
+
static int mmu_check_root(struct kvm_vcpu *vcpu, gfn_t root_gfn)
{
int ret = 0;
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 6d7c368c92e7..2a881afc1fd0 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -5423,8 +5423,8 @@ static int handle_invvpid(struct kvm_vcpu *vcpu)
/*
* Sync the shadow page tables if EPT is disabled, L1 is invalidating
- * linear mappings for L2 (tagged with L2's VPID). Free all roots as
- * VPIDs are not tracked in the MMU role.
+ * linear mappings for L2 (tagged with L2's VPID). Free all guest
+ * roots as VPIDs are not tracked in the MMU role.
*
* Note, this operates on root_mmu, not guest_mmu, as L1 and L2 share
* an MMU when EPT is disabled.
@@ -5432,8 +5432,7 @@ static int handle_invvpid(struct kvm_vcpu *vcpu)
* TODO: sync only the affected SPTEs for INVDIVIDUAL_ADDR.
*/
if (!enable_ept)
- kvm_mmu_free_roots(vcpu, &vcpu->arch.root_mmu,
- KVM_MMU_ROOTS_ALL);
+ kvm_mmu_free_guest_mode_roots(vcpu, &vcpu->arch.root_mmu);
return nested_vmx_succeed(vcpu);
}
--
2.32.0.rc1.229.g3e70b5a671-goog
