From patchwork Tue Sep 14 15:48:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 12494059 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1EFC5C433EF for ; Tue, 14 Sep 2021 15:50:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 068E261247 for ; Tue, 14 Sep 2021 15:50:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235375AbhINPwB (ORCPT ); Tue, 14 Sep 2021 11:52:01 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:45165 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235588AbhINPvh (ORCPT ); Tue, 14 Sep 2021 11:51:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1631634619; 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=ZLaQBdWcYWzUQ/0WAKIV5Ngb/tBLBqu2kjrdS0k3qs4=; b=Ddeg5QV9BNUupKjD61fk1aCcb2LiMZLXIeIW1SBJTNGedSDZ4qSbA8CIviHDtgQ+o18Jyv nUF8WygSpKGeLpM7MwqXCYy9RI5h5dvG2bpRgLkraJY5WE+L2dAc1tTo+uXRmXewnq386L eHlF4tj3LE4PY6ctzQ996BxJR2urjD8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-120-jJMMEyswODyQwe_9ektIEA-1; Tue, 14 Sep 2021 11:50:16 -0400 X-MC-Unique: jJMMEyswODyQwe_9ektIEA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 78F5F835DE0; Tue, 14 Sep 2021 15:50:14 +0000 (UTC) Received: from localhost.localdomain (unknown [10.35.206.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id A97A65C1BB; Tue, 14 Sep 2021 15:50:00 +0000 (UTC) From: Maxim Levitsky To: kvm@vger.kernel.org Cc: Vitaly Kuznetsov , Paolo Bonzini , Borislav Petkov , Bandan Das , linux-kernel@vger.kernel.org (open list), Joerg Roedel , Ingo Molnar , Wei Huang , Sean Christopherson , linux-kselftest@vger.kernel.org (open list:KERNEL SELFTEST FRAMEWORK), Maxim Levitsky , "H. Peter Anvin" , Jim Mattson , Thomas Gleixner , x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)), Shuah Khan , Wanpeng Li Subject: [PATCH 11/14] KVM: x86: nSVM: implement nested VMLOAD/VMSAVE Date: Tue, 14 Sep 2021 18:48:22 +0300 Message-Id: <20210914154825.104886-12-mlevitsk@redhat.com> In-Reply-To: <20210914154825.104886-1-mlevitsk@redhat.com> References: <20210914154825.104886-1-mlevitsk@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This was tested by booting L1,L2,L3 (all Linux) and checking that no VMLOAD/VMSAVE vmexits happened. Signed-off-by: Maxim Levitsky --- arch/x86/kvm/svm/nested.c | 35 +++++++++++++++++++++++++++++------ arch/x86/kvm/svm/svm.c | 7 +++++++ arch/x86/kvm/svm/svm.h | 12 +++++++++--- 3 files changed, 45 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index aadbff9b6514..29b5d0f85960 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -119,6 +119,20 @@ static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu) vcpu->arch.walk_mmu = &vcpu->arch.root_mmu; } +static bool nested_vmcb_needs_vls_intercept(struct vcpu_svm *svm) +{ + if (!svm->v_vmload_vmsave_enabled) + return true; + + if (!nested_npt_enabled(svm)) + return true; + + if (!(svm->nested.ctl.virt_ext & VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK)) + return true; + + return false; +} + void recalc_intercepts(struct vcpu_svm *svm) { struct vmcb_control_area *c, *h, *g; @@ -159,8 +173,17 @@ void recalc_intercepts(struct vcpu_svm *svm) if (!intercept_smi) vmcb_clr_intercept(c, INTERCEPT_SMI); - vmcb_set_intercept(c, INTERCEPT_VMLOAD); - vmcb_set_intercept(c, INTERCEPT_VMSAVE); + if (nested_vmcb_needs_vls_intercept(svm)) { + /* + * If the virtual VMLOAD/VMSAVE is not enabled for the L2, + * we must intercept these instructions to correctly + * emulate them in case L1 doesn't intercept them. + */ + vmcb_set_intercept(c, INTERCEPT_VMLOAD); + vmcb_set_intercept(c, INTERCEPT_VMSAVE); + } else { + WARN_ON(!(c->virt_ext & VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK)); + } } static void copy_vmcb_control_area(struct vmcb_control_area *dst, @@ -387,10 +410,7 @@ static void nested_save_pending_event_to_vmcb12(struct vcpu_svm *svm, vmcb12->control.exit_int_info = exit_int_info; } -static inline bool nested_npt_enabled(struct vcpu_svm *svm) -{ - return svm->nested.ctl.nested_ctl & SVM_NESTED_CTL_NP_ENABLE; -} + static void nested_svm_transition_tlb_flush(struct kvm_vcpu *vcpu) { @@ -570,6 +590,9 @@ static void nested_vmcb02_prepare_control(struct vcpu_svm *svm) svm->vmcb->control.virt_ext |= (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK); + if (!nested_vmcb_needs_vls_intercept(svm)) + svm->vmcb->control.virt_ext |= VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK; + nested_svm_transition_tlb_flush(vcpu); /* Enter Guest-Mode */ diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 66f99e8d804c..6504e40e0985 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1013,6 +1013,9 @@ static __init void svm_set_cpu_caps(void) if (lbrv) kvm_cpu_cap_set(X86_FEATURE_LBRV); + if (vls) + kvm_cpu_cap_set(X86_FEATURE_V_VMSAVE_VMLOAD); + /* Nested VM can receive #VMEXIT instead of triggering #GP */ kvm_cpu_cap_set(X86_FEATURE_SVME_ADDR_CHK); } @@ -4090,6 +4093,8 @@ static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) svm->lbrv_enabled = lbrv && guest_cpuid_has(vcpu, X86_FEATURE_LBRV); + svm->v_vmload_vmsave_enabled = vls && guest_cpuid_has(vcpu, X86_FEATURE_V_VMSAVE_VMLOAD); + svm_recalc_instruction_intercepts(vcpu, svm); /* For sev guests, the memory encryption bit is not reserved in CR3. */ @@ -4129,6 +4134,8 @@ static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) set_msr_interception(vcpu, svm->msrpm, MSR_IA32_SYSENTER_EIP, 0, 0); set_msr_interception(vcpu, svm->msrpm, MSR_IA32_SYSENTER_ESP, 0, 0); + + svm->v_vmload_vmsave_enabled = false; } else { /* * If hardware supports Virtual VMLOAD VMSAVE then enable it diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index c9a81e18707d..029340a7fbcc 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -159,9 +159,10 @@ struct vcpu_svm { unsigned int3_injected; unsigned long int3_rip; - /* cached guest cpuid flags for faster access */ - bool nrips_enabled : 1; - bool lbrv_enabled : 1; + /* optional nested SVM features that are enabled for this guest */ + bool nrips_enabled : 1; + bool lbrv_enabled : 1; + bool v_vmload_vmsave_enabled : 1; u32 ldr_reg; u32 dfr_reg; @@ -409,6 +410,11 @@ static inline bool gif_set(struct vcpu_svm *svm) return !!(svm->vcpu.arch.hflags & HF_GIF_MASK); } +static inline bool nested_npt_enabled(struct vcpu_svm *svm) +{ + return svm->nested.ctl.nested_ctl & SVM_NESTED_CTL_NP_ENABLE; +} + /* svm.c */ #define MSR_INVALID 0xffffffffU