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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 357E1C3F2D2 for ; Thu, 5 Mar 2020 20:10:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0F8B5207FD for ; Thu, 5 Mar 2020 20:10:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726220AbgCEUKC (ORCPT ); Thu, 5 Mar 2020 15:10:02 -0500 Received: from mga18.intel.com ([134.134.136.126]:58402 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726007AbgCEUKC (ORCPT ); Thu, 5 Mar 2020 15:10:02 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN 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; 05 Mar 2020 12:10:01 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,519,1574150400"; d="scan'208";a="287766600" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by FMSMGA003.fm.intel.com with ESMTP; 05 Mar 2020 12:10:00 -0800 Date: Thu, 5 Mar 2020 12:10:00 -0800 From: Sean Christopherson To: Vitaly Kuznetsov Cc: Paolo Bonzini , Jim Mattson , Wanpeng Li , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/2] KVM: VMX: untangle VMXON revision_id setting when using eVMCS Message-ID: <20200305201000.GQ11500@linux.intel.com> References: <20200305183725.28872-1-vkuznets@redhat.com> <20200305183725.28872-3-vkuznets@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200305183725.28872-3-vkuznets@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 05, 2020 at 07:37:25PM +0100, Vitaly Kuznetsov wrote: > As stated in alloc_vmxon_regions(), VMXON region needs to be tagged with > revision id from MSR_IA32_VMX_BASIC even in case of eVMCS. The logic to > do so is not very straightforward: first, we set > hdr.revision_id = KVM_EVMCS_VERSION in alloc_vmcs_cpu() just to reset it > back to vmcs_config.revision_id in alloc_vmxon_regions(). Simplify this by > introducing 'enum vmcs_type' parameter to alloc_vmcs_cpu(). > > No functional change intended. > > Signed-off-by: Vitaly Kuznetsov > --- ... > + * However, even though not explicitly documented by TLFS, VMXArea > + * passed as VMXON argument should still be marked with revision_id > + * reported by physical CPU. LOL, nice. > + */ > + if (type != VMXON_REGION && static_branch_unlikely(&enable_evmcs)) > vmcs->hdr.revision_id = KVM_EVMCS_VERSION; > else > vmcs->hdr.revision_id = vmcs_config.revision_id; > > - if (shadow) > + if (type == SHADOW_VMCS_REGION) > vmcs->hdr.shadow_vmcs = 1; > return vmcs; > } > -struct vmcs *alloc_vmcs_cpu(bool shadow, int cpu, gfp_t flags); > +enum vmcs_type { > + VMXON_REGION, > + VMCS_REGION, > + SHADOW_VMCS_REGION, > +}; > + > +struct vmcs *alloc_vmcs_cpu(enum vmcs_type type, int cpu, gfp_t flags); > void free_vmcs(struct vmcs *vmcs); > int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs); > void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs); > @@ -498,8 +504,8 @@ void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs); > > static inline struct vmcs *alloc_vmcs(bool shadow) I think it'd be cleaner overall to take "enum vmcs_type" in alloc_vmcs(). Then the ternary operator goes away and the callers (all two of 'em) are self-documenting. E.g. diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 79c7764c77b1..2c8a0a1386b1 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4566,7 +4566,7 @@ static struct vmcs *alloc_shadow_vmcs(struct kvm_vcpu *vcpu) WARN_ON(loaded_vmcs == &vmx->vmcs01 && loaded_vmcs->shadow_vmcs); if (!loaded_vmcs->shadow_vmcs) { - loaded_vmcs->shadow_vmcs = alloc_vmcs(true); + loaded_vmcs->shadow_vmcs = alloc_vmcs(SHADOW_VMCS_REGION); if (loaded_vmcs->shadow_vmcs) vmcs_clear(loaded_vmcs->shadow_vmcs); } diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 5bdf6919de83..4634f6d7d55a 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2605,7 +2605,7 @@ void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs) int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs) { - loaded_vmcs->vmcs = alloc_vmcs(false); + loaded_vmcs->vmcs = alloc_vmcs(VMCS_REGION); if (!loaded_vmcs->vmcs) return -ENOMEM; diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index 4c327030bb9c..a5eb92638ac2 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -502,10 +502,10 @@ void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs); void loaded_vmcs_init(struct loaded_vmcs *loaded_vmcs); void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs); -static inline struct vmcs *alloc_vmcs(bool shadow) +static inline struct vmcs *alloc_vmcs(enum vmcs_type type) { - return alloc_vmcs_cpu(shadow ? SHADOW_VMCS_REGION : VMCS_REGION, - raw_smp_processor_id(), GFP_KERNEL_ACCOUNT); + return alloc_vmcs_cpu(type, raw_smp_processor_id(), + GFP_KERNEL_ACCOUNT); } u64 construct_eptp(struct kvm_vcpu *vcpu, unsigned long root_hpa); > { > - return alloc_vmcs_cpu(shadow, raw_smp_processor_id(), > - GFP_KERNEL_ACCOUNT); > + return alloc_vmcs_cpu(shadow ? SHADOW_VMCS_REGION : VMCS_REGION, > + raw_smp_processor_id(), GFP_KERNEL_ACCOUNT); > } > > u64 construct_eptp(struct kvm_vcpu *vcpu, unsigned long root_hpa); > -- > 2.24.1 >