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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 AABA1C74A35 for ; Wed, 10 Jul 2019 20:11:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7D8712087F for ; Wed, 10 Jul 2019 20:11:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728335AbfGJULr (ORCPT ); Wed, 10 Jul 2019 16:11:47 -0400 Received: from mga11.intel.com ([192.55.52.93]:48183 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726111AbfGJULr (ORCPT ); Wed, 10 Jul 2019 16:11:47 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Jul 2019 13:11:47 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,475,1557212400"; d="scan'208";a="159863794" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.165]) by orsmga008.jf.intel.com with ESMTP; 10 Jul 2019 13:11:46 -0700 Date: Wed, 10 Jul 2019 13:11:46 -0700 From: Sean Christopherson To: Krish Sadhukhan Cc: Paolo Bonzini , kvm@vger.kernel.org, rkrcmar@redhat.com, jmattson@google.com Subject: Re: [PATCH 2/5] KVM: nVMX: Skip VM-Exit Control vmentry checks that are necessary only if VMCS12 is dirty Message-ID: <20190710201146.GG4348@linux.intel.com> References: <20190707071147.11651-1-krish.sadhukhan@oracle.com> <20190707071147.11651-3-krish.sadhukhan@oracle.com> <9e0b1aba-8cf6-733c-dc4d-63aa61fcddd8@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <9e0b1aba-8cf6-733c-dc4d-63aa61fcddd8@oracle.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, Jul 10, 2019 at 12:18:55PM -0700, Krish Sadhukhan wrote: > > On 7/10/19 7:28 AM, Paolo Bonzini wrote: > >On 07/07/19 09:11, Krish Sadhukhan wrote: > >> if (!vmx_control_verify(vmcs12->vm_exit_controls, > >> vmx->nested.msrs.exit_ctls_low, > >>- vmx->nested.msrs.exit_ctls_high) || > >>- nested_vmx_check_exit_msr_switch_controls(vcpu, vmcs12)) > >>+ vmx->nested.msrs.exit_ctls_high)) > >>+ return -EINVAL; > >>+ > >Exit controls are not shadowed, are they? > > No, they aren't.   However, I see that prepare_vmcs02_constant_state() which > is called in the path of prepare_vmcs02_early_full() writes those Exit > Control fields: > >        vmcs_write32(VM_EXIT_MSR_STORE_COUNT, 0); >         vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, > __pa(vmx->msr_autoload.host.val)); >         vmcs_write64(VM_ENTRY_MSR_LOAD_ADDR, > __pa(vmx->msr_autoload.guest.val)); That's writing L0's values into vmcs02 when vmcs02 is first used. L1's MSR load lists are processed purely in software, e.g. nested_vmx_load_msr(). The vmcs12 entries are consumed by KVM on every nested transition to emulate the load/store functionality, but the validity of the *controls* only needs to be checked when vmcs12 is dirty. > > > Should we add these fields to the shadow list then ? > > > > >Paolo