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=-2.3 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 3F021C352A4 for ; Sat, 15 Feb 2020 07:35:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 13250206D7 for ; Sat, 15 Feb 2020 07:35:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726090AbgBOHf3 (ORCPT ); Sat, 15 Feb 2020 02:35:29 -0500 Received: from mga07.intel.com ([134.134.136.100]:10016 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725844AbgBOHf3 (ORCPT ); Sat, 15 Feb 2020 02:35:29 -0500 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 orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Feb 2020 23:35:28 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,443,1574150400"; d="scan'208";a="227857382" Received: from kfinglet-mobl.ger.corp.intel.com (HELO localhost) ([10.252.22.140]) by orsmga008.jf.intel.com with ESMTP; 14 Feb 2020 23:35:18 -0800 Date: Sat, 15 Feb 2020 09:35:19 +0200 From: Jarkko Sakkinen To: Jethro Beekman Cc: linux-kernel@vger.kernel.org, x86@kernel.org, linux-sgx@vger.kernel.org, akpm@linux-foundation.org, dave.hansen@intel.com, sean.j.christopherson@intel.com, nhorman@redhat.com, npmccallum@redhat.com, haitao.huang@intel.com, andriy.shevchenko@linux.intel.com, tglx@linutronix.de, kai.svahn@intel.com, bp@alien8.de, josh@joshtriplett.org, luto@kernel.org, kai.huang@intel.com, rientjes@google.com, cedric.xing@intel.com, puiterwijk@redhat.com, linux-security-module@vger.kernel.org, Suresh Siddha , Haitao Huang Subject: Re: [PATCH v26 10/22] x86/sgx: Linux Enclave Driver Message-ID: <20200215073519.GE9958@linux.intel.com> References: <20200209212609.7928-1-jarkko.sakkinen@linux.intel.com> <20200209212609.7928-11-jarkko.sakkinen@linux.intel.com> <20200215073234.GD9958@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200215073234.GD9958@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 15, 2020 at 09:32:34AM +0200, Jarkko Sakkinen wrote: > On Thu, Feb 13, 2020 at 02:59:52PM +0100, Jethro Beekman wrote: > > Besides only partially measuring a page, there are some other fringe > > cases that are technically possible, although I haven't seen any > > toolchains that do that. These include not interleaving EADD and > > EEXTEND, not using logical ordering for the EEXTENDs, and call EEXTEND > > multiple times on the same chunk. Maximum interoperability would > > require supporting any EADD/EEXTEND sequence. > > The reason why EEXTEND deals with chunks is nothing to do with the > granularity but just to amortize the algorithm. I did ask about this > and this is the answer that I got. I mean asked from people who have been involed in the development of this CPU feature. /Jarkko