From: Avi Kivity Subject: [PATCH 5/5] KVM: MMU: Fix check for cr3 outside guest memory Date: Mon, 26 Apr 2010 11:48:43 +0300 Message-ID: <1272271723-9070-6-git-send-email-avi@redhat.com> References: <1272271723-9070-1-git-send-email-avi@redhat.com> Cc: kvm@vger.kernel.org To: Marcelo Tosatti Return-path: Received: from mx1.redhat.com ([209.132.183.28]:25274 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750804Ab0DZIsq (ORCPT ); Mon, 26 Apr 2010 04:48:46 -0400 Received: from int-mx03.intmail.prod.int.phx2.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.16]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o3Q8mjoZ012821 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 26 Apr 2010 04:48:46 -0400 Received: from cleopatra.tlv.redhat.com (cleopatra.tlv.redhat.com [10.35.255.11]) by int-mx03.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o3Q8mjAx027592 for ; Mon, 26 Apr 2010 04:48:45 -0400 In-Reply-To: <1272271723-9070-1-git-send-email-avi@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Fir direct maps, root_gfn or cr3 are meaningless. This hasn't bitten us because no sane guest sets cr3 outside its own memory even in real mode. Signed-off-by: Avi Kivity --- arch/x86/kvm/mmu.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 6e925b3..e3acc9e 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2083,7 +2083,7 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu) } else root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT; - if (mmu_check_root(vcpu, root_gfn)) + if (!direct && mmu_check_root(vcpu, root_gfn)) return 1; sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, PT32_ROOT_LEVEL, direct, -- 1.7.0.4