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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 6A095C46475 for ; Mon, 5 Nov 2018 17:36:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2C36B20866 for ; Mon, 5 Nov 2018 17:36:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C36B20866 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-sgx-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387538AbeKFC4w (ORCPT ); Mon, 5 Nov 2018 21:56:52 -0500 Received: from mga14.intel.com ([192.55.52.115]:46489 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387515AbeKFC4w (ORCPT ); Mon, 5 Nov 2018 21:56:52 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Nov 2018 09:36:08 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,468,1534834800"; d="scan'208";a="271544497" Received: from wenjiewa-mobl2.ccr.corp.intel.com (HELO localhost) ([10.249.254.60]) by orsmga005.jf.intel.com with ESMTP; 05 Nov 2018 09:35:58 -0800 Date: Mon, 5 Nov 2018 19:35:57 +0200 From: Jarkko Sakkinen To: Andy Shevchenko Cc: "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , Platform Driver , linux-sgx@vger.kernel.org, Dave Hansen , sean.j.christopherson@intel.com, nhorman@redhat.com, npmccallum@redhat.com, serge.ayoun@intel.com, shay.katz-zamir@intel.com, haitao.huang@intel.com, mark.shanahan@intel.com, Andy Shevchenko , suresh.b.siddha@intel.com, Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Reinette Chatre , "Rafael J. Wysocki" , "Kirill A. Shutemov" , Linux Kernel Mailing List Subject: Re: [PATCH v15 16/23] x86/sgx: Enumerate and track EPC sections Message-ID: <20181105173557.GF4502@linux.intel.com> References: <20181102231320.29164-1-jarkko.sakkinen@linux.intel.com> <20181102231320.29164-17-jarkko.sakkinen@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org Message-ID: <20181105173557.u_To-eZa_f9Y2q2lTCPqYV2XPPVMQ5ocpLXTkv2YCPo@z> On Sat, Nov 03, 2018 at 03:22:34PM +0200, Andy Shevchenko wrote: > On Sat, Nov 3, 2018 at 1:17 AM Jarkko Sakkinen > wrote: > > > > From: Sean Christopherson > > > > Enumerate Enclave Page Cache (EPC) sections via CPUID and add the data > > structures necessary to track EPC pages so that they can be allocated, > > freed and managed. As a system may have multiple EPC sections, invoke > > CPUID on SGX sub-leafs until an invalid leaf is encountered. > > > > On NUMA systems, a node can have at most one bank. A bank can be at > > most part of two nodes. SGX supports both nodes with a single memory > > controller and also sub-cluster nodes with severals memory controllers > > on a single die. > > > > For simplicity, support a maximum of eight EPC sections. Current > > client hardware supports only a single section, while upcoming server > > hardware will support at most eight sections. Bounding the number of > > sections also allows the section ID to be embedded along with a page's > > offset in a single unsigned long, enabling easy retrieval of both the > > VA and PA for a given page. > > > + iounmap(section->va); > > > + section->va = ioremap_cache(addr, size); > > + if (!section->va) > > + return -ENOMEM; > > I forgot if it's a place in code on which we discussed ioremap() vs. > memremap() call. > And I forgot why the conclusion is to leave ioremap(). > > Sorry, if I'm mistaken. Thanks for pointing this out. It very well might I have either 1. forgotten to do the switch. 2. had some open about it that I forgot to ask. Anyway, I'll check this and at minimum document the reason to the change log if there is one to keep the ioremap(). /Jarkko