[PATCH v2 03/18] KVM: x86/mmu: WARN if PAE roots linger after kvm_mmu_unload

Paolo Bonzini
2022-02-17T21:04:07Z

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/mmu/mmu.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 296f8723f9ae..a67071ac80f3 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5086,12 +5086,21 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
return r;
}

+static void __kvm_mmu_unload(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
+{
+ int i;
+ kvm_mmu_free_roots(vcpu, mmu, KVM_MMU_ROOTS_ALL);
+ WARN_ON(VALID_PAGE(mmu->root_hpa));
+ if (mmu->pae_root) {
+ for (i = 0; i < 4; ++i)
+ WARN_ON(IS_VALID_PAE_ROOT(mmu->pae_root[i]));
+ }
+}
+
void kvm_mmu_unload(struct kvm_vcpu *vcpu)
{
- kvm_mmu_free_roots(vcpu, &vcpu->arch.root_mmu, KVM_MMU_ROOTS_ALL);
- WARN_ON(VALID_PAGE(vcpu->arch.root_mmu.root_hpa));
- kvm_mmu_free_roots(vcpu, &vcpu->arch.guest_mmu, KVM_MMU_ROOTS_ALL);
- WARN_ON(VALID_PAGE(vcpu->arch.guest_mmu.root_hpa));
+ __kvm_mmu_unload(vcpu, &vcpu->arch.root_mmu);
+ __kvm_mmu_unload(vcpu, &vcpu->arch.guest_mmu);
}

static bool need_remote_flush(u64 old, u64 new)
--
2.31.1