From patchwork Tue Sep 17 08:53:03 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Yang, Weijiang" X-Patchwork-Id: 11148291 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 300FE16B1 for ; Tue, 17 Sep 2019 08:53:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 11F7D21924 for ; Tue, 17 Sep 2019 08:53:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726330AbfIQIw5 (ORCPT ); Tue, 17 Sep 2019 04:52:57 -0400 Received: from mga18.intel.com ([134.134.136.126]:37165 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726044AbfIQIwm (ORCPT ); Tue, 17 Sep 2019 04:52:42 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Sep 2019 01:52:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,515,1559545200"; d="scan'208";a="193695544" Received: from unknown (HELO local-michael-cet-test.sh.intel.com) ([10.239.159.128]) by FMSMGA003.fm.intel.com with ESMTP; 17 Sep 2019 01:52:40 -0700 From: Yang Weijiang To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, sean.j.christopherson@intel.com Cc: mst@redhat.com, rkrcmar@redhat.com, jmattson@google.com, yu.c.zhang@intel.com, alazar@bitdefender.com, Yang Weijiang Subject: [PATCH v5 8/9] mmu: spp: Enable Lazy mode SPP protection Date: Tue, 17 Sep 2019 16:53:03 +0800 Message-Id: <20190917085304.16987-9-weijiang.yang@intel.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20190917085304.16987-1-weijiang.yang@intel.com> References: <20190917085304.16987-1-weijiang.yang@intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org To deal with SPP protected 4KB pages within hugepage(2MB,1GB etc), the hugepage entry is first zapped when set subpage permission, then in tdp_page_fault(), it checks whether the gfn should be mapped to PT_PAGE_TABLE_LEVEL or PT_DIRECTORY_LEVEL level depending on gfn inclusion of SPP protected page range. Suggested-by: Paolo Bonzini Signed-off-by: Yang Weijiang --- arch/x86/kvm/mmu.c | 14 ++++++++++++ arch/x86/kvm/vmx/spp.c | 48 ++++++++++++++++++++++++++++++++++++++++++ arch/x86/kvm/vmx/spp.h | 4 ++++ 3 files changed, 66 insertions(+) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index a632c6b3c326..c9c430d2c7e3 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3240,6 +3240,17 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t gpa, int write, map_writable); direct_pte_prefetch(vcpu, it.sptep); ++vcpu->stat.pf_fixed; + if (level == PT_PAGE_TABLE_LEVEL) { + struct kvm_subpage sbp = {0}; + int pages; + + sbp.base_gfn = gfn; + sbp.npages = 1; + pages = kvm_spp_get_permission(vcpu->kvm, &sbp); + if (pages == 1 && sbp.access_map[0] != FULL_SPP_ACCESS) + kvm_spp_mark_protection(vcpu->kvm, &sbp); + } + return ret; } @@ -4183,6 +4194,9 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code, if (level > PT_DIRECTORY_LEVEL && !check_hugepage_cache_consistency(vcpu, gfn, level)) level = PT_DIRECTORY_LEVEL; + + check_spp_protection(vcpu, gfn, &force_pt_level,&level); + gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1); } diff --git a/arch/x86/kvm/vmx/spp.c b/arch/x86/kvm/vmx/spp.c index b6fc2e313b59..7f7a3749c35b 100644 --- a/arch/x86/kvm/vmx/spp.c +++ b/arch/x86/kvm/vmx/spp.c @@ -547,6 +547,54 @@ inline u64 construct_spptp(unsigned long root_hpa) } EXPORT_SYMBOL_GPL(construct_spptp); +bool is_spp_protected(struct kvm_memory_slot *slot, gfn_t gfn, int level) +{ + int page_num = KVM_PAGES_PER_HPAGE(level); + int i; + gfn &= ~(page_num - 1); + + for (i = 0; i < page_num; ++i) { + if (*gfn_to_subpage_wp_info(slot, gfn + i) != FULL_SPP_ACCESS) + return true; + } + return false; +} + +bool check_spp_protection(struct kvm_vcpu *vcpu, gfn_t gfn, + bool *force_pt_level, int *level) +{ + struct kvm *kvm = vcpu->kvm; + struct kvm_memory_slot *slot; + u32 access; + + if (!kvm->arch.spp_active) + return false; + + slot = gfn_to_memslot(kvm, gfn); + + if (!slot) + return false; + + if (*level == PT_PAGE_TABLE_LEVEL) { + access = *gfn_to_subpage_wp_info(slot, gfn); + + if (access != FULL_SPP_ACCESS) { + *force_pt_level = true; + return true; + } + } else { + if (is_spp_protected(slot, gfn, PT_PDPE_LEVEL)) { + bool protected = is_spp_protected(slot, gfn, + PT_DIRECTORY_LEVEL); + *level = protected ? PT_PAGE_TABLE_LEVEL : + PT_DIRECTORY_LEVEL; + *force_pt_level = protected; + return true; + } + } + return false; +} + int kvm_vm_ioctl_get_subpages(struct kvm *kvm, struct kvm_subpage *spp_info) { diff --git a/arch/x86/kvm/vmx/spp.h b/arch/x86/kvm/vmx/spp.h index 8925a6ca4d3b..ed7852bb6b33 100644 --- a/arch/x86/kvm/vmx/spp.h +++ b/arch/x86/kvm/vmx/spp.h @@ -4,9 +4,13 @@ #define FULL_SPP_ACCESS ((u32)((1ULL << 32) - 1)) +int kvm_spp_get_permission(struct kvm *kvm, struct kvm_subpage *spp_info); +int kvm_spp_mark_protection(struct kvm *kvm, struct kvm_subpage *spp_info); bool is_spp_spte(struct kvm_mmu_page *sp); void restore_spp_bit(u64 *spte); bool was_spp_armed(u64 spte); +bool check_spp_protection(struct kvm_vcpu *vcpu, gfn_t gfn, + bool *force_pt_level, int *level); inline u64 construct_spptp(unsigned long root_hpa); int kvm_vm_ioctl_get_subpages(struct kvm *kvm, struct kvm_subpage *spp_info);