From patchwork Mon Feb 7 15:54:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 12737590 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 ADF43C35276 for ; Mon, 7 Feb 2022 16:05:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1442411AbiBGQEd (ORCPT ); Mon, 7 Feb 2022 11:04:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378178AbiBGP76 (ORCPT ); Mon, 7 Feb 2022 10:59:58 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 219F9C0401CE for ; Mon, 7 Feb 2022 07:59:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1644249597; 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=oU3s7CnCjp2O1VaC3lW5tk3dKh1EHix/EeWBDaZUEPI=; b=Hq3ku4E8WMfwOKfLn7zLujJ0u6zAcYzQ1YEmApnxnDWbeohVVknB3jTScnY/SEQ0LWEDYB kLGHx/AdJcTmZd9BKu1jbeqT2M49Tn6ZL8p+7KRjF2GAiwX0SWa3kwjgwZExfiyi2q2Fpo N+uD5dpog6XUrDbAEMlouNEhEdZHjpY= 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-17-kR5m2bS0MdWEc_u9IHssKg-1; Mon, 07 Feb 2022 10:59:54 -0500 X-MC-Unique: kR5m2bS0MdWEc_u9IHssKg-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 955F7100D680; Mon, 7 Feb 2022 15:59:49 +0000 (UTC) Received: from localhost.localdomain (unknown [10.40.192.15]) by smtp.corp.redhat.com (Postfix) with ESMTP id C6E917DE38; Mon, 7 Feb 2022 15:59:34 +0000 (UTC) From: Maxim Levitsky To: kvm@vger.kernel.org Cc: Tony Luck , "Chang S. Bae" , Thomas Gleixner , Wanpeng Li , Ingo Molnar , Vitaly Kuznetsov , Pawan Gupta , Dave Hansen , Paolo Bonzini , linux-kernel@vger.kernel.org, Rodrigo Vivi , "H. Peter Anvin" , intel-gvt-dev@lists.freedesktop.org, Joonas Lahtinen , Joerg Roedel , Sean Christopherson , David Airlie , Zhi Wang , Brijesh Singh , Jim Mattson , x86@kernel.org, Daniel Vetter , Borislav Petkov , Zhenyu Wang , Kan Liang , Jani Nikula , Maxim Levitsky Subject: [PATCH RESEND 24/30] KVM: x86: nSVM: implement nested VMLOAD/VMSAVE Date: Mon, 7 Feb 2022 17:54:41 +0200 Message-Id: <20220207155447.840194-25-mlevitsk@redhat.com> In-Reply-To: <20220207155447.840194-1-mlevitsk@redhat.com> References: <20220207155447.840194-1-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 | 8 +++++++- 3 files changed, 43 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 4a228a76b27d7..bdcb23c76e89e 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -120,6 +120,20 @@ 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; @@ -161,8 +175,17 @@ 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 bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) @@ -426,10 +449,7 @@ 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) { @@ -607,6 +627,9 @@ 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 76aa6054d9db2..0f068da098d9f 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1051,6 +1051,8 @@ static inline void init_vmcb_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 @@ -3993,6 +3995,8 @@ static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) svm->tsc_scaling_enabled = tsc_scaling && guest_cpuid_has(vcpu, X86_FEATURE_TSCRATEMSR); 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. */ @@ -4799,6 +4803,9 @@ 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); } diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index 0012ba5affcba..e8ffd458a5575 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -217,10 +217,11 @@ struct vcpu_svm { unsigned int3_injected; unsigned long int3_rip; - /* cached guest cpuid flags for faster access */ + /* optional nested SVM features that are enabled for this guest */ bool nrips_enabled : 1; bool tsc_scaling_enabled : 1; bool lbrv_enabled : 1; + bool v_vmload_vmsave_enabled : 1; u32 ldr_reg; u32 dfr_reg; @@ -468,6 +469,11 @@ 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