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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS 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 C79BBC433E0 for ; Thu, 21 Jan 2021 00:00:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 77CA623715 for ; Thu, 21 Jan 2021 00:00:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727125AbhATX67 (ORCPT ); Wed, 20 Jan 2021 18:58:59 -0500 Received: from mga04.intel.com ([192.55.52.120]:64353 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404055AbhATXX6 (ORCPT ); Wed, 20 Jan 2021 18:23:58 -0500 IronPort-SDR: ifgVO9Ic9E6IqS1mATzLF/aym3n35qrVyMV1ZlhWLXmpz5hSLX8XjlgPOwGgoD19H7DX6eBSyZ hnCiPt+mv0UQ== X-IronPort-AV: E=McAfee;i="6000,8403,9870"; a="176619738" X-IronPort-AV: E=Sophos;i="5.79,362,1602572400"; d="scan'208";a="176619738" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jan 2021 15:23:14 -0800 IronPort-SDR: t34X6Og3oAmwrF1m/oEYbcdZQdrj4DDZUxEHOTb5bV7EnY5btKb0r1/slD57DyPDNwBPWYBooT ubDfab+FGLJw== X-IronPort-AV: E=Sophos;i="5.79,362,1602572400"; d="scan'208";a="391720531" Received: from gapoveda-mobl1.amr.corp.intel.com (HELO khuang2-desk.gar.corp.intel.com) ([10.254.79.186]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jan 2021 15:23:11 -0800 Date: Thu, 21 Jan 2021 12:23:08 +1300 From: Kai Huang To: Jarkko Sakkinen Cc: linux-sgx@vger.kernel.org, kvm@vger.kernel.org, x86@kernel.org, seanjc@google.com, luto@kernel.org, dave.hansen@intel.com, haitao.huang@intel.com, pbonzini@redhat.com, bp@alien8.de, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com Subject: Re: [RFC PATCH v2 01/26] x86/cpufeatures: Add SGX1 and SGX2 sub-features Message-Id: <20210121122308.8d920c9d652f58824fe87f3e@intel.com> In-Reply-To: References: <87385f646120a3b5b34dc20480dbce77b8005acd.1610935432.git.kai.huang@intel.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, 20 Jan 2021 13:50:12 +0200 Jarkko Sakkinen wrote: > On Mon, Jan 18, 2021 at 04:26:49PM +1300, Kai Huang wrote: > > From: Sean Christopherson > > > > Add SGX1 and SGX2 feature flags, via CPUID.0x12.0x0.EAX, as scattered > > features. As part of virtualizing SGX, KVM will expose the SGX CPUID > > leafs to its guest, and to do so correctly needs to query hardware and > > kernel support for SGX1 and SGX2. > > This commit message is missing reasoning behind scattered vs. own word. > > Please just document the reasoning, that's all. OK. Will do. How about: "Add SGX1 and SGX2 feature flags, via CPUID.0x12.0x0.EAX, as scattered features, since adding a new leaf for only two bits would be wasteful." ? > > /Jarkko