From 376c53c2b30d4a1955240f59f4ecd959aa118f92 Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Thu, 10 Jul 2008 20:54:29 -0300 Subject: [PATCH] KVM: MMU: improve invalid shadow root page handling Harden kvm_mmu_zap_page() against invalid root pages that had been shadowed from memslots that are gone. Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity --- arch/x86/kvm/mmu.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index ff7cf632175b..7f57da663826 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -930,14 +930,17 @@ static void kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp) } kvm_mmu_page_unlink_children(kvm, sp); if (!sp->root_count) { - if (!sp->role.metaphysical) + if (!sp->role.metaphysical && !sp->role.invalid) unaccount_shadowed(kvm, sp->gfn); hlist_del(&sp->hash_link); kvm_mmu_free_page(kvm, sp); } else { + int invalid = sp->role.invalid; list_move(&sp->link, &kvm->arch.active_mmu_pages); sp->role.invalid = 1; kvm_reload_remote_mmus(kvm); + if (!sp->role.metaphysical && !invalid) + unaccount_shadowed(kvm, sp->gfn); } kvm_mmu_reset_last_pte_updated(kvm); } -- 2.39.5