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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH,UNPARSEABLE_RELAY,USER_AGENT_MUTT autolearn=ham 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 799E0C5CFEB for ; Mon, 9 Jul 2018 18:53:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 283C02089D for ; Mon, 9 Jul 2018 18:53:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="UhmoKn2L" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 283C02089D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933314AbeGISxQ (ORCPT ); Mon, 9 Jul 2018 14:53:16 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:57756 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932607AbeGISxP (ORCPT ); Mon, 9 Jul 2018 14:53:15 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w69IhwxC144523; Mon, 9 Jul 2018 18:52:50 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2018-07-02; bh=vs1dtWJdXllV9NEAVGI4UaCHV390jV9yOa1BsmGnals=; b=UhmoKn2Lyfrai3uGhAvo4qFnIllNqqjVhg9k5FpnHra+8ssBSK0duBiRT3AumNuBiq1H QcBIJfQ84f/PwwFt53fWROyp3iwmYCps2Ywz4vOZ/XeBxmA1jHixFPBo/2vYEZFH3yhc kZksqwUW1TLJssDixEgz2aA5f7SIhkgKuziafq+YcYLeuoiBaEUGHub5NXO6VPpcRnp5 MYLA0l+m0SzAZ+lWL3sAWMKOBGDRqmS7NKGzxuIPwZeADTrmJXM677gsvmQiX/0ouvy0 MpQVeGrNJcPSC6is8GOo1cDJRop11akNoJWhCr3xUusuEscmOesoRFQAErRuX5S2280N yg== Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by aserp2120.oracle.com with ESMTP id 2k2p7dngvq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 09 Jul 2018 18:52:50 +0000 Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w69IqnDr025271 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 9 Jul 2018 18:52:50 GMT Received: from abhmp0010.oracle.com (abhmp0010.oracle.com [141.146.116.16]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id w69IqmVk006018; Mon, 9 Jul 2018 18:52:48 GMT Received: from char.us.oracle.com (/10.137.176.158) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 09 Jul 2018 11:52:48 -0700 Received: by char.us.oracle.com (Postfix, from userid 1000) id E65B26A00C3; Mon, 9 Jul 2018 14:52:46 -0400 (EDT) Date: Mon, 9 Jul 2018 14:52:46 -0400 From: Konrad Rzeszutek Wilk To: Dave Hansen Cc: "Kirill A. Shutemov" , Ingo Molnar , x86@kernel.org, Thomas Gleixner , "H. Peter Anvin" , Tom Lendacky , Kai Huang , Jacob Pan , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCHv4 18/18] x86: Introduce CONFIG_X86_INTEL_MKTME Message-ID: <20180709185246.GC17368@char.us.oracle.com> References: <20180626142245.82850-1-kirill.shutemov@linux.intel.com> <20180626142245.82850-19-kirill.shutemov@linux.intel.com> <20180709183656.GK6873@char.US.ORACLE.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.8.3 (2017-05-23) X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8949 signatures=668705 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=798 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1806210000 definitions=main-1807090212 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 09, 2018 at 11:44:33AM -0700, Dave Hansen wrote: > On 07/09/2018 11:36 AM, Konrad Rzeszutek Wilk wrote: > > On Tue, Jun 26, 2018 at 05:22:45PM +0300, Kirill A. Shutemov wrote: > > Rip out the X86? > >> + bool "Intel Multi-Key Total Memory Encryption" > >> + select DYNAMIC_PHYSICAL_MASK > >> + select PAGE_EXTENSION > > > > And maybe select 5-page? > > Why? It's not a strict dependency. You *can* build a 4-level kernel > and run it on smaller systems. Sure, but in one of his commits he mentions that we may run in overlapping physical memory if we use 4-level paging. Hence why not just move to 5-level paging and simplify this. > > >> + depends on X86_64 && CPU_SUP_INTEL > >> + ---help--- > >> + Say yes to enable support for Multi-Key Total Memory Encryption. > >> + This requires an Intel processor that has support of the feature. > >> + > >> + Multikey Total Memory Encryption (MKTME) is a technology that allows > >> + transparent memory encryption in and upcoming Intel platforms. > > > > How about saying which CPUs? Or just dropping this? > > We don't have any information about specifically which processors with > have this feature to share. But, this config text does tell someone > that they can't use this feature on today's platforms. > > We _did_ say this for previous features (protection keys stands out > where we said it was for "Skylake Servers" IIRC), but we are not yet > able to do the same for this feature.