From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5C28BC433F5 for ; Mon, 21 Feb 2022 16:23:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1380258AbiBUQYB (ORCPT ); Mon, 21 Feb 2022 11:24:01 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:53404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1380219AbiBUQXR (ORCPT ); Mon, 21 Feb 2022 11:23:17 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 908AC2716B for ; Mon, 21 Feb 2022 08:22:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1645460572; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JgC7K68EGURf/5nseSGFk+gLjMEs+In6PNVCqkhk4fs=; b=GTHlIOOLzJU2LuGgAB5hrhgVcRfSQGLK0w3mPV+FnUoqf9lafCxven22PhaMUi8KlpY7wP t7dqZwZtrtosts9xJO412ytGSGeAvj1unRrLHkt9aXNMdvOXbNffVivy/Ksye+tFBmYoPb Hx/qtG8rck8Boe93o6NuBBGzlSrhqqc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-528-mIOYH9jIOYSOB1LiQNxKzw-1; Mon, 21 Feb 2022 11:22:49 -0500 X-MC-Unique: mIOYH9jIOYSOB1LiQNxKzw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2C44E801B0F; Mon, 21 Feb 2022 16:22:48 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id C375D77468; Mon, 21 Feb 2022 16:22:47 +0000 (UTC) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: dmatlack@google.com, seanjc@google.com Subject: [PATCH v2 08/25] KVM: x86/mmu: split cpu_mode from mmu_role Date: Mon, 21 Feb 2022 11:22:26 -0500 Message-Id: <20220221162243.683208-9-pbonzini@redhat.com> In-Reply-To: <20220221162243.683208-1-pbonzini@redhat.com> References: <20220221162243.683208-1-pbonzini@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Snapshot the state of the processor registers that govern page walk into a new field of struct kvm_mmu. This is a more natural representation than having it *mostly* in mmu_role but not exclusively; the delta right now is represented in other fields, such as root_level. The nested MMU now has only the CPU mode; and in fact the new function kvm_calc_cpu_mode is analogous to the previous kvm_calc_nested_mmu_role, except that it has role.base.direct equal to CR0.PG. It is not clear what the code meant by "setting role.base.direct to true to detect bogus usage of the nested MMU". Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/mmu/mmu.c | 107 ++++++++++++++++++++------------ arch/x86/kvm/mmu/paging_tmpl.h | 2 +- 3 files changed, 68 insertions(+), 42 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 92855d3984a7..cc268116eb3f 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -433,6 +433,7 @@ struct kvm_mmu { struct kvm_mmu_page *sp); void (*invlpg)(struct kvm_vcpu *vcpu, gva_t gva, hpa_t root_hpa); struct kvm_mmu_root_info root; + union kvm_mmu_role cpu_mode; union kvm_mmu_role mmu_role; u8 root_level; u8 shadow_root_level; diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 7c835253a330..1af898f0cf87 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -221,7 +221,7 @@ BUILD_MMU_ROLE_REGS_ACCESSOR(efer, lma, EFER_LMA); #define BUILD_MMU_ROLE_ACCESSOR(base_or_ext, reg, name) \ static inline bool __maybe_unused is_##reg##_##name(struct kvm_mmu *mmu) \ { \ - return !!(mmu->mmu_role. base_or_ext . reg##_##name); \ + return !!(mmu->cpu_mode. base_or_ext . reg##_##name); \ } BUILD_MMU_ROLE_ACCESSOR(ext, cr0, pg); BUILD_MMU_ROLE_ACCESSOR(base, cr0, wp); @@ -4680,6 +4680,39 @@ static void paging32_init_context(struct kvm_mmu *context) context->direct_map = false; } +static union kvm_mmu_role +kvm_calc_cpu_mode(struct kvm_vcpu *vcpu, const struct kvm_mmu_role_regs *regs) +{ + union kvm_mmu_role role = {0}; + + role.base.access = ACC_ALL; + role.base.smm = is_smm(vcpu); + role.base.guest_mode = is_guest_mode(vcpu); + role.base.direct = !____is_cr0_pg(regs); + if (!role.base.direct) { + role.base.efer_nx = ____is_efer_nx(regs); + role.base.cr0_wp = ____is_cr0_wp(regs); + role.base.smep_andnot_wp = ____is_cr4_smep(regs) && !____is_cr0_wp(regs); + role.base.smap_andnot_wp = ____is_cr4_smap(regs) && !____is_cr0_wp(regs); + role.base.has_4_byte_gpte = !____is_cr4_pae(regs); + role.base.level = role_regs_to_root_level(regs); + + role.ext.cr0_pg = 1; + role.ext.cr4_pae = ____is_cr4_pae(regs); + role.ext.cr4_smep = ____is_cr4_smep(regs); + role.ext.cr4_smap = ____is_cr4_smap(regs); + role.ext.cr4_pse = ____is_cr4_pse(regs); + + /* PKEY and LA57 are active iff long mode is active. */ + role.ext.cr4_pke = ____is_efer_lma(regs) && ____is_cr4_pke(regs); + role.ext.cr4_la57 = ____is_efer_lma(regs) && ____is_cr4_la57(regs); + role.ext.efer_lma = ____is_efer_lma(regs); + } + + role.ext.valid = 1; + return role; +} + static union kvm_mmu_role kvm_calc_mmu_role_common(struct kvm_vcpu *vcpu, const struct kvm_mmu_role_regs *regs) { @@ -4739,13 +4772,16 @@ static void init_kvm_tdp_mmu(struct kvm_vcpu *vcpu, const struct kvm_mmu_role_regs *regs) { struct kvm_mmu *context = &vcpu->arch.root_mmu; - union kvm_mmu_role new_role = + union kvm_mmu_role cpu_mode = kvm_calc_cpu_mode(vcpu, regs); + union kvm_mmu_role mmu_role = kvm_calc_tdp_mmu_root_page_role(vcpu, regs); - if (new_role.as_u64 == context->mmu_role.as_u64) + if (cpu_mode.as_u64 == context->cpu_mode.as_u64 && + mmu_role.as_u64 == context->mmu_role.as_u64) return; - context->mmu_role.as_u64 = new_role.as_u64; + context->cpu_mode.as_u64 = cpu_mode.as_u64; + context->mmu_role.as_u64 = mmu_role.as_u64; context->page_fault = kvm_tdp_page_fault; context->sync_page = nonpaging_sync_page; context->invlpg = NULL; @@ -4800,13 +4836,15 @@ kvm_calc_shadow_mmu_root_page_role(struct kvm_vcpu *vcpu, } static void shadow_mmu_init_context(struct kvm_vcpu *vcpu, struct kvm_mmu *context, - const struct kvm_mmu_role_regs *regs, - union kvm_mmu_role new_role) + union kvm_mmu_role cpu_mode, + union kvm_mmu_role mmu_role) { - if (new_role.as_u64 == context->mmu_role.as_u64) + if (cpu_mode.as_u64 == context->cpu_mode.as_u64 && + mmu_role.as_u64 == context->mmu_role.as_u64) return; - context->mmu_role.as_u64 = new_role.as_u64; + context->cpu_mode.as_u64 = cpu_mode.as_u64; + context->mmu_role.as_u64 = mmu_role.as_u64; if (!is_cr0_pg(context)) nonpaging_init_context(context); @@ -4814,10 +4852,10 @@ static void shadow_mmu_init_context(struct kvm_vcpu *vcpu, struct kvm_mmu *conte paging64_init_context(context); else paging32_init_context(context); - context->root_level = role_regs_to_root_level(regs); + context->root_level = cpu_mode.base.level; reset_guest_paging_metadata(vcpu, context); - context->shadow_root_level = new_role.base.level; + context->shadow_root_level = mmu_role.base.level; reset_shadow_zero_bits_mask(vcpu, context); } @@ -4826,10 +4864,11 @@ static void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, const struct kvm_mmu_role_regs *regs) { struct kvm_mmu *context = &vcpu->arch.root_mmu; - union kvm_mmu_role new_role = + union kvm_mmu_role cpu_mode = kvm_calc_cpu_mode(vcpu, regs); + union kvm_mmu_role mmu_role = kvm_calc_shadow_mmu_root_page_role(vcpu, regs); - shadow_mmu_init_context(vcpu, context, regs, new_role); + shadow_mmu_init_context(vcpu, context, cpu_mode, mmu_role); } static union kvm_mmu_role @@ -4854,11 +4893,10 @@ void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0, .cr4 = cr4 & ~X86_CR4_PKE, .efer = efer, }; - union kvm_mmu_role new_role; + union kvm_mmu_role cpu_mode = kvm_calc_cpu_mode(vcpu, ®s); + union kvm_mmu_role mmu_role = kvm_calc_shadow_npt_root_page_role(vcpu, ®s);; - new_role = kvm_calc_shadow_npt_root_page_role(vcpu, ®s); - - shadow_mmu_init_context(vcpu, context, ®s, new_role); + shadow_mmu_init_context(vcpu, context, cpu_mode, mmu_role); kvm_mmu_new_pgd(vcpu, nested_cr3); } EXPORT_SYMBOL_GPL(kvm_init_shadow_npt_mmu); @@ -4881,7 +4919,6 @@ kvm_calc_shadow_ept_root_page_role(struct kvm_vcpu *vcpu, bool accessed_dirty, role.base.guest_mode = true; role.base.access = ACC_ALL; - /* EPT, and thus nested EPT, does not consume CR0, CR4, nor EFER. */ role.ext.word = 0; role.ext.execonly = execonly; role.ext.valid = 1; @@ -4895,12 +4932,14 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, { struct kvm_mmu *context = &vcpu->arch.guest_mmu; u8 level = vmx_eptp_page_walk_level(new_eptp); - union kvm_mmu_role new_role = + union kvm_mmu_role new_mode = kvm_calc_shadow_ept_root_page_role(vcpu, accessed_dirty, execonly, level); - if (new_role.as_u64 != context->mmu_role.as_u64) { - context->mmu_role.as_u64 = new_role.as_u64; + if (new_mode.as_u64 != context->cpu_mode.as_u64) { + /* EPT, and thus nested EPT, does not consume CR0, CR4, nor EFER. */ + context->cpu_mode.as_u64 = new_mode.as_u64; + context->mmu_role.as_u64 = new_mode.as_u64; context->shadow_root_level = level; @@ -4933,36 +4972,19 @@ static void init_kvm_softmmu(struct kvm_vcpu *vcpu, context->inject_page_fault = kvm_inject_page_fault_shadow; } -static union kvm_mmu_role -kvm_calc_nested_mmu_role(struct kvm_vcpu *vcpu, const struct kvm_mmu_role_regs *regs) -{ - union kvm_mmu_role role; - - role = kvm_calc_shadow_root_page_role_common(vcpu, regs); - - /* - * Nested MMUs are used only for walking L2's gva->gpa, they never have - * shadow pages of their own and so "direct" has no meaning. Set it - * to "true" to try to detect bogus usage of the nested MMU. - */ - role.base.direct = true; - role.base.level = role_regs_to_root_level(regs); - return role; -} - static void init_kvm_nested_mmu(struct kvm_vcpu *vcpu, const struct kvm_mmu_role_regs *regs) { - union kvm_mmu_role new_role = kvm_calc_nested_mmu_role(vcpu, regs); + union kvm_mmu_role new_mode = kvm_calc_cpu_mode(vcpu, regs); struct kvm_mmu *g_context = &vcpu->arch.nested_mmu; - if (new_role.as_u64 == g_context->mmu_role.as_u64) + if (new_mode.as_u64 == g_context->cpu_mode.as_u64) return; - g_context->mmu_role.as_u64 = new_role.as_u64; + g_context->cpu_mode.as_u64 = new_mode.as_u64; g_context->get_guest_pgd = kvm_get_guest_cr3; g_context->get_pdptr = kvm_pdptr_read; g_context->inject_page_fault = kvm_inject_page_fault; - g_context->root_level = new_role.base.level; + g_context->root_level = new_mode.base.level; /* * L2 page tables are never shadowed, so there is no need to sync @@ -5020,6 +5042,9 @@ void kvm_mmu_after_set_cpuid(struct kvm_vcpu *vcpu) vcpu->arch.root_mmu.mmu_role.ext.valid = 0; vcpu->arch.guest_mmu.mmu_role.ext.valid = 0; vcpu->arch.nested_mmu.mmu_role.ext.valid = 0; + vcpu->arch.root_mmu.cpu_mode.ext.valid = 0; + vcpu->arch.guest_mmu.cpu_mode.ext.valid = 0; + vcpu->arch.nested_mmu.cpu_mode.ext.valid = 0; kvm_mmu_reset_context(vcpu); /* diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h index d1d17d28e81b..e1c2ecb4ddee 100644 --- a/arch/x86/kvm/mmu/paging_tmpl.h +++ b/arch/x86/kvm/mmu/paging_tmpl.h @@ -323,7 +323,7 @@ static inline bool FNAME(is_last_gpte)(struct kvm_mmu *mmu, * is not reserved and does not indicate a large page at this level, * so clear PT_PAGE_SIZE_MASK in gpte if that is the case. */ - gpte &= level - (PT32_ROOT_LEVEL + mmu->mmu_role.ext.cr4_pse); + gpte &= level - (PT32_ROOT_LEVEL + mmu->cpu_mode.ext.cr4_pse); #endif /* * PG_LEVEL_4K always terminates. The RHS has bit 7 set -- 2.31.1