From patchwork Thu Jun 11 14:02:28 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 29562 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n5BE5Yk8023350 for ; Thu, 11 Jun 2009 14:05:35 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752077AbZFKOF3 (ORCPT ); Thu, 11 Jun 2009 10:05:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752065AbZFKOF2 (ORCPT ); Thu, 11 Jun 2009 10:05:28 -0400 Received: from mx2.redhat.com ([66.187.237.31]:55350 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750856AbZFKOF0 (ORCPT ); Thu, 11 Jun 2009 10:05:26 -0400 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n5BE5TpX026903 for ; Thu, 11 Jun 2009 10:05:29 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n5BE5SAX023755; Thu, 11 Jun 2009 10:05:28 -0400 Received: from amt.cnet (vpn-10-91.str.redhat.com [10.32.10.91]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n5BE5PBb021792; Thu, 11 Jun 2009 10:05:26 -0400 Received: from amt.cnet (amt.cnet [127.0.0.1]) by amt.cnet (Postfix) with ESMTP id F25AF27500A; Thu, 11 Jun 2009 11:04:58 -0300 (BRT) Received: (from marcelo@localhost) by amt.cnet (8.14.3/8.14.3/Submit) id n5BE4v3C005932; Thu, 11 Jun 2009 11:04:57 -0300 Message-Id: <20090611140416.885566345@localhost.localdomain> References: <20090611140224.457657937@localhost.localdomain> In-Reply-To: <4A307819.6010503@redhat.com> User-Agent: quilt/0.46-1 Date: Thu, 11 Jun 2009 11:02:28 -0300 From: Marcelo Tosatti To: avi@redhat.com Cc: kvm@vger.kernel.org, Marcelo Tosatti Subject: [patch 4/5] KVM: VMX: EPT misconfiguration handler Content-Disposition: inline; filename=vmx-misconfig-handler X-Scanned-By: MIMEDefang 2.58 on 172.16.27.26 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Handler for EPT misconfiguration which checks for valid state in the shadow pagetables, printing the spte on each level. The separate WARN_ONs are useful for kerneloops.org. Signed-off-by: Marcelo Tosatti Index: kvm/arch/x86/kvm/vmx.c =================================================================== --- kvm.orig/arch/x86/kvm/vmx.c +++ kvm/arch/x86/kvm/vmx.c @@ -3233,6 +3233,90 @@ static int handle_ept_violation(struct k return kvm_mmu_page_fault(vcpu, gpa & PAGE_MASK, 0); } +static u64 ept_rsvd_mask(u64 *sptep, int level) +{ + int i; + u64 mask = 0; + + for (i = 51; i > boot_cpu_data.x86_phys_bits; i--) + mask |= (1ULL << i); + + if (level > 2) + /* bits 7:3 reserved */ + mask |= 0xf8; + else if (level == 2) { + if (*sptep & (1ULL << 7)) + /* 2MB ref, bits 20:12 reserved */ + mask |= 0x1ff000; + else + /* bits 6:3 reserved */ + mask |= 0x78; + } + + return mask; +} + +static void ept_misconfig_inspect_spte(struct kvm_vcpu *vcpu, u64 *sptep, + int level) +{ + printk(KERN_ERR "%s: sptep %p spte 0x%llx level %d\n", + __func__, sptep, *sptep, level); + + /* 010b (write-only) */ + WARN_ON((*sptep & 0x7) == 0x2); + + /* 110b (write/execute) */ + WARN_ON((*sptep & 0x7) == 0x6); + + /* 100b (execute-only) and value not supported by logical processor */ + if (!cpu_has_vmx_ept_execute_only()) + WARN_ON((*sptep & 0x7) == 0x4); + + /* not 000b */ + if ((*sptep & 0x7)) { + u64 rsvd_bits = *sptep & ept_rsvd_mask(sptep, level); + + if (rsvd_bits != 0) { + printk(KERN_ERR "%s: rsvd_bits = 0x%llx\n", + __func__, rsvd_bits); + WARN_ON(1); + } + + if (level == 1 || (level == 2 && (*sptep & (1ULL << 7)))) { + u64 ept_mem_type = (*sptep & 0x38) >> 3; + + if (ept_mem_type == 2 || ept_mem_type == 3 || + ept_mem_type == 7) { + printk(KERN_ERR "%s: ept_mem_type=0x%llx\n", + __func__, ept_mem_type); + WARN_ON(1); + } + } + } +} + +static int handle_ept_misconfig(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) +{ + u64 *sptes[4]; + int nr_sptes, i; + gpa_t gpa; + + gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS); + + printk(KERN_ERR "EPT: Misconfiguration.\n"); + printk(KERN_ERR "EPT: GPA: 0x%llx\n", gpa); + + nr_sptes = kvm_mmu_get_spte_hierarchy(vcpu, gpa, sptes); + + for (i = PT64_ROOT_LEVEL; i > PT64_ROOT_LEVEL - nr_sptes; --i) + ept_misconfig_inspect_spte(vcpu, sptes[i-1], i); + + kvm_run->exit_reason = KVM_EXIT_UNKNOWN; + kvm_run->hw.hardware_exit_reason = EXIT_REASON_EPT_MISCONFIG; + + return 0; +} + static int handle_nmi_window(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) { u32 cpu_based_vm_exec_control; @@ -3303,8 +3387,9 @@ static int (*kvm_vmx_exit_handlers[])(st [EXIT_REASON_APIC_ACCESS] = handle_apic_access, [EXIT_REASON_WBINVD] = handle_wbinvd, [EXIT_REASON_TASK_SWITCH] = handle_task_switch, - [EXIT_REASON_EPT_VIOLATION] = handle_ept_violation, [EXIT_REASON_MCE_DURING_VMENTRY] = handle_machine_check, + [EXIT_REASON_EPT_VIOLATION] = handle_ept_violation, + [EXIT_REASON_EPT_MISCONFIG] = handle_ept_misconfig, }; static const int kvm_vmx_max_exit_handlers =