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 X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 E9C92C43381 for ; Wed, 3 Mar 2021 12:56:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A9FA9601FF for ; Wed, 3 Mar 2021 12:56:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1443345AbhCCL66 (ORCPT ); Wed, 3 Mar 2021 06:58:58 -0500 Received: from mga09.intel.com ([134.134.136.24]:46711 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238280AbhCCF5o (ORCPT ); Wed, 3 Mar 2021 00:57:44 -0500 IronPort-SDR: 4df1HfbWa1TGM3weHNFlY3K3u8vCKkjzmAgydyuyLoahB11GdDRky52wQN7nuORokoOcwPCdOb +3A1es2vbJsg== X-IronPort-AV: E=McAfee;i="6000,8403,9911"; a="187225218" X-IronPort-AV: E=Sophos;i="5.81,219,1610438400"; d="scan'208";a="187225218" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Mar 2021 21:56:54 -0800 IronPort-SDR: PbsOBCdr6YFQPm3VhY1tyo14Q++dIXx3Q8TGVQxLMuzUpfhkLyskwcdSWgz3bwhfjYNyezIG0O KcTqKTKkYyYw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.81,219,1610438400"; d="scan'208";a="399516650" Received: from local-michael-cet-test.sh.intel.com (HELO localhost) ([10.239.159.166]) by fmsmga008.fm.intel.com with ESMTP; 02 Mar 2021 21:56:52 -0800 Date: Wed, 3 Mar 2021 14:09:39 +0800 From: Yang Weijiang To: Vitaly Kuznetsov Cc: Sean Christopherson , Yang Weijiang , pbonzini@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] KVM: nVMX: Sync L2 guest CET states between L1/L2 Message-ID: <20210303060939.GA8243@local-michael-cet-test.sh.intel.com> References: <20210225030951.17099-1-weijiang.yang@intel.com> <20210225030951.17099-2-weijiang.yang@intel.com> <87y2f5etc2.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87y2f5etc2.fsf@vitty.brq.redhat.com> User-Agent: Mutt/1.11.3 (2019-02-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 02, 2021 at 11:35:41AM +0100, Vitaly Kuznetsov wrote: > Sean Christopherson writes: > > > +Vitaly > > > > On Thu, Feb 25, 2021, Yang Weijiang wrote: > >> These fields are rarely updated by L1 QEMU/KVM, sync them when L1 is trying to > >> read/write them and after they're changed. If CET guest entry-load bit is not > >> set by L1 guest, migrate them to L2 manaully. > >> > >> Suggested-by: Sean Christopherson > >> Signed-off-by: Yang Weijiang > >> > >> change in v2: > >> - Per Sean's review feedback, change CET guest states as rarely-updated fields. > >> And also migrate L1's CET states to L2 if the entry-load bit is not set. > >> - Opportunistically removed one blank line. > >> --- > >> arch/x86/kvm/cpuid.c | 1 - > >> arch/x86/kvm/vmx/nested.c | 29 +++++++++++++++++++++++++++++ > >> arch/x86/kvm/vmx/vmx.h | 3 +++ > >> 3 files changed, 32 insertions(+), 1 deletion(-) > >> > >> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > >> index 46087bca9418..afc97122c05c 100644 > >> --- a/arch/x86/kvm/cpuid.c > >> +++ b/arch/x86/kvm/cpuid.c > >> @@ -143,7 +143,6 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu) > >> } > >> vcpu->arch.guest_supported_xss = > >> (((u64)best->edx << 32) | best->ecx) & supported_xss; > >> - > >> } else { > >> vcpu->arch.guest_supported_xss = 0; > >> } > >> diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c > >> index 9728efd529a1..1703b8874fad 100644 > >> --- a/arch/x86/kvm/vmx/nested.c > >> +++ b/arch/x86/kvm/vmx/nested.c > >> @@ -2516,6 +2516,12 @@ static void prepare_vmcs02_rare(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12) > >> vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, vmx->msr_autoload.guest.nr); > >> > >> set_cr4_guest_host_mask(vmx); > >> + > >> + if (kvm_cet_supported()) { > > > > This needs to be conditioned on CET coming from vmcs12, it's on the loading of > > host state on VM-Exit that is unconditional (if CET is supported). > > > > if (kvm_cet_supported() && vmx->nested.nested_run_pending && > > (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_CET_STATE)) { > > > > I also assume these should be guarded by one of the eVMCS fields, though a quick > > search of the public docs didn't provide a hit on the CET fields. > > > > Vitaly, any idea if these will be GUEST_GRP2 or something else? > > > > The latest published TLFS I see is 6.0b and it doesn't list anything CET > related in eVMCS v1.0 :-( So I agree with Paolo: we just need to adjust > EVMCS1_UNSUPPORTED_VMENTRY_CTRL/ EVMCS1_UNSUPPORTED_VMEXIT_CTRL for now > and enable it separately later. > Thanks Vitaly and Paolo. New patches have been sent to community. > >> + vmcs_writel(GUEST_SSP, vmcs12->guest_ssp); > >> + vmcs_writel(GUEST_S_CET, vmcs12->guest_s_cet); > >> + vmcs_writel(GUEST_INTR_SSP_TABLE, vmcs12->guest_ssp_tbl); > >> + } > >> } > > > > -- > Vitaly