KVM: x86/mmu: Check every prev_roots in __kvm_mmu_free_obsolete_roots()

When freeing obsolete previous roots, check prev_roots as intended, not
the current root.

Signed-off-by: Shaoqin Huang <shaoqin.huang@intel.com>
Fixes: fec964ffc9c3 ("KVM: x86/mmu: Zap only obsolete roots if a root shadow page is zapped")
Message-Id: <20220607005905.2933378-1-shaoqin.huang@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index efe5a3dca1e092e89dfcde77c8df65d4a5befcde..e46771e9519112625a95a38f84d64da16f24845a 100644 (file)
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5179,7 +5179,7 @@ static void __kvm_mmu_free_obsolete_roots(struct kvm *kvm, struct kvm_mmu *mmu)
                roots_to_free |= KVM_MMU_ROOT_CURRENT;
 
        for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
-               if (is_obsolete_root(kvm, mmu->root.hpa))
+               if (is_obsolete_root(kvm, mmu->prev_roots[i].hpa))
                        roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
        }