From patchwork Thu Feb 6 22:08:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 11369333 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 57CF0921 for ; Thu, 6 Feb 2020 22:08:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 40D8620658 for ; Thu, 6 Feb 2020 22:08:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727942AbgBFWIj (ORCPT ); Thu, 6 Feb 2020 17:08:39 -0500 Received: from mga14.intel.com ([192.55.52.115]:64211 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727496AbgBFWIi (ORCPT ); Thu, 6 Feb 2020 17:08:38 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 06 Feb 2020 14:08:37 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,411,1574150400"; d="scan'208";a="404625088" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.202]) by orsmga005.jf.intel.com with ESMTP; 06 Feb 2020 14:08:37 -0800 From: Sean Christopherson To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/7] KVM: nVMX: Allow L1 to use 5-level page walks for nested EPT Date: Thu, 6 Feb 2020 14:08:32 -0800 Message-Id: <20200206220836.22743-4-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200206220836.22743-1-sean.j.christopherson@intel.com> References: <20200206220836.22743-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Add support for 5-level nested EPT, and advertise said support in the EPT capabilities MSR. KVM's MMU can already handle 5-level legacy page tables, there's no reason to force an L1 VMM to use shadow paging if it wants to employ 5-level page tables. Signed-off-by: Sean Christopherson --- arch/x86/include/asm/vmx.h | 12 ++++++++++++ arch/x86/kvm/mmu/mmu.c | 11 ++++++----- arch/x86/kvm/vmx/nested.c | 21 +++++++++++++++++---- arch/x86/kvm/vmx/vmx.c | 3 +-- 4 files changed, 36 insertions(+), 11 deletions(-) diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h index d716fe938fc0..e77d8a05597d 100644 --- a/arch/x86/include/asm/vmx.h +++ b/arch/x86/include/asm/vmx.h @@ -495,6 +495,18 @@ enum vmcs_field { VMX_EPT_EXECUTABLE_MASK) #define VMX_EPT_MT_MASK (7ull << VMX_EPT_MT_EPTE_SHIFT) +static inline u8 vmx_eptp_page_walk_level(u64 eptp) +{ + u64 encoded_level = eptp & VMX_EPTP_PWL_MASK; + + if (encoded_level == VMX_EPTP_PWL_5) + return 5; + + /* @eptp must be pre-validated by the caller. */ + WARN_ON_ONCE(encoded_level != VMX_EPTP_PWL_4); + return 4; +} + /* The mask to use to trigger an EPT Misconfiguration in order to track MMIO */ #define VMX_EPT_MISCONFIG_WX_VALUE (VMX_EPT_WRITABLE_MASK | \ VMX_EPT_EXECUTABLE_MASK) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 84eeb61d06aa..33baa2b79652 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -4999,14 +4999,14 @@ EXPORT_SYMBOL_GPL(kvm_init_shadow_mmu); static union kvm_mmu_role kvm_calc_shadow_ept_root_page_role(struct kvm_vcpu *vcpu, bool accessed_dirty, - bool execonly) + bool execonly, u8 level) { union kvm_mmu_role role = {0}; /* SMM flag is inherited from root_mmu */ role.base.smm = vcpu->arch.root_mmu.mmu_role.base.smm; - role.base.level = PT64_ROOT_4LEVEL; + role.base.level = level; role.base.gpte_is_8_bytes = true; role.base.direct = false; role.base.ad_disabled = !accessed_dirty; @@ -5030,9 +5030,10 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, bool accessed_dirty, gpa_t new_eptp) { struct kvm_mmu *context = vcpu->arch.mmu; + u8 level = vmx_eptp_page_walk_level(new_eptp); union kvm_mmu_role new_role = kvm_calc_shadow_ept_root_page_role(vcpu, accessed_dirty, - execonly); + execonly, level); __kvm_mmu_new_cr3(vcpu, new_eptp, new_role.base, false); @@ -5040,7 +5041,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, if (new_role.as_u64 == context->mmu_role.as_u64) return; - context->shadow_root_level = PT64_ROOT_4LEVEL; + context->shadow_root_level = level; context->nx = true; context->ept_ad = accessed_dirty; @@ -5049,7 +5050,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, context->sync_page = ept_sync_page; context->invlpg = ept_invlpg; context->update_pte = ept_update_pte; - context->root_level = PT64_ROOT_4LEVEL; + context->root_level = level; context->direct_map = false; context->mmu_role.as_u64 = new_role.as_u64; diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 95b3f4306ac2..11f98ee10ac5 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -2581,9 +2581,19 @@ static bool valid_ept_address(struct kvm_vcpu *vcpu, u64 address) return false; } - /* only 4 levels page-walk length are valid */ - if (CC((address & VMX_EPTP_PWL_MASK) != VMX_EPTP_PWL_4)) + /* Page-walk levels validity. */ + switch (address & VMX_EPTP_PWL_MASK) { + case VMX_EPTP_PWL_5: + if (CC(!(vmx->nested.msrs.ept_caps & VMX_EPT_PAGE_WALK_5_BIT))) + return false; + break; + case VMX_EPTP_PWL_4: + if (CC(!(vmx->nested.msrs.ept_caps & VMX_EPT_PAGE_WALK_4_BIT))) + return false; + break; + default: return false; + } /* Reserved bits should not be set */ if (CC(address >> maxphyaddr || ((address >> 7) & 0x1f))) @@ -6056,8 +6066,11 @@ void nested_vmx_setup_ctls_msrs(struct nested_vmx_msrs *msrs, u32 ept_caps, /* nested EPT: emulate EPT also to L1 */ msrs->secondary_ctls_high |= SECONDARY_EXEC_ENABLE_EPT; - msrs->ept_caps = VMX_EPT_PAGE_WALK_4_BIT | - VMX_EPTP_WB_BIT | VMX_EPT_INVEPT_BIT; + msrs->ept_caps = + VMX_EPT_PAGE_WALK_4_BIT | + VMX_EPT_PAGE_WALK_5_BIT | + VMX_EPTP_WB_BIT | + VMX_EPT_INVEPT_BIT; if (cpu_has_vmx_ept_execute_only()) msrs->ept_caps |= VMX_EPT_EXECUTE_ONLY_BIT; diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 46161f4e4b42..da70ef12266c 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2970,9 +2970,8 @@ void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) static int get_ept_level(struct kvm_vcpu *vcpu) { - /* Nested EPT currently only supports 4-level walks. */ if (is_guest_mode(vcpu) && nested_cpu_has_ept(get_vmcs12(vcpu))) - return 4; + return vmx_eptp_page_walk_level(nested_ept_get_cr3(vcpu)); if (cpu_has_vmx_ept_5levels() && (cpuid_maxphyaddr(vcpu) > 48)) return 5; return 4;