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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 A2CECC83007 for ; Wed, 29 Apr 2020 05:23:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 827C2206D6 for ; Wed, 29 Apr 2020 05:23:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726426AbgD2FXg (ORCPT ); Wed, 29 Apr 2020 01:23:36 -0400 Received: from mga01.intel.com ([192.55.52.88]:7748 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726158AbgD2FXg (ORCPT ); Wed, 29 Apr 2020 01:23:36 -0400 IronPort-SDR: jsT+BjkEikvwukXB1RUxgJX5tqTn8D2ZLTh3uVvAeHx4hy4QV8OOQPfUsbYABdC1mV7A5WXDLu BdEOrjYm8KuQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Apr 2020 22:23:36 -0700 IronPort-SDR: 5OKfLfolJg8d2aPIx2CQty7wHH+40bT32y0OHQ1NYAk0Aw2JzAe8kxQTPaA6g1IdNjuOcR+KgJ t0Ynz1mRpS4w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,330,1583222400"; d="scan'208";a="246735509" Received: from ramibuso-mobl.ger.corp.intel.com (HELO localhost) ([10.249.47.170]) by orsmga007.jf.intel.com with ESMTP; 28 Apr 2020 22:23:27 -0700 Date: Wed, 29 Apr 2020 08:23:29 +0300 From: Jarkko Sakkinen To: "Dr. Greg" Cc: torvalds@linux-foundation.org, 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 Subject: Re: [PATCH v29 00/20] Intel SGX foundations Message-ID: <20200429052329.GD8452@linux.intel.com> References: <20200421215316.56503-1-jarkko.sakkinen@linux.intel.com> <20200426165753.GA11046@wind.enjellic.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200426165753.GA11046@wind.enjellic.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Apr 26, 2020 at 11:57:53AM -0500, Dr. Greg wrote: > On Wed, Apr 22, 2020 at 12:52:56AM +0300, Jarkko Sakkinen wrote: > > Good day, I hope the weekend is going well for everyone. > > > Intel(R) SGX is a set of CPU instructions that can be used by applications > > to set aside private regions of code and data. The code outside the enclave > > is disallowed to access the memory inside the enclave by the CPU access > > control. > > > > ... [ elided ] .. > > > > The current implementation requires that the firmware sets > > IA32_SGXLEPUBKEYHASH* MSRs as writable so that ultimately the kernel can > > decide what enclaves it wants run. The implementation does not create > > any bottlenecks to support read-only MSRs later on. > > It seems highly unlikely that a driver implementation with any type of > support for read-only launch control registers would ever get into the > kernel. All one needs to do is review the conversations that Matthew > Garrett's lockdown patches engender to get a sense of that, ie: > > https://lwn.net/Articles/818277/ We do not require read-only MSRs. /Jarkko