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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 60F94C48BE3 for ; Fri, 21 Jun 2019 01:16:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3A5822085A for ; Fri, 21 Jun 2019 01:16:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725921AbfFUBQ0 (ORCPT ); Thu, 20 Jun 2019 21:16:26 -0400 Received: from mga14.intel.com ([192.55.52.115]:64919 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725906AbfFUBQ0 (ORCPT ); Thu, 20 Jun 2019 21:16:26 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Jun 2019 18:16:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,398,1557212400"; d="scan'208";a="160840397" Received: from mudigirx-mobl1.gar.corp.intel.com (HELO localhost) ([10.252.61.12]) by fmsmga008.fm.intel.com with ESMTP; 20 Jun 2019 18:16:19 -0700 Date: Fri, 21 Jun 2019 04:16:18 +0300 From: Jarkko Sakkinen To: Sean Christopherson Cc: linux-sgx@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, Bill Roberts , Casey Schaufler , James Morris , Dave Hansen , Cedric Xing , Andy Lutomirski , Jethro Beekman , "Dr . Greg Wettstein" , Stephen Smalley Subject: Re: [RFC PATCH v4 04/12] x86/sgx: Require userspace to define enclave pages' protection bits Message-ID: <20190621011618.GH20474@linux.intel.com> References: <20190619222401.14942-1-sean.j.christopherson@intel.com> <20190619222401.14942-5-sean.j.christopherson@intel.com> <20190621010753.GG20474@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190621010753.GG20474@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-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Fri, Jun 21, 2019 at 04:07:53AM +0300, Jarkko Sakkinen wrote: > /** > * sgx_calc_vma_prot_intersection() - Calculate intersection of the permissions > * for a VMA > * @encl: an enclave > * @vma: a VMA inside the enclave > * > * Iterate through the page addresses inside the VMA and calculate a bitmask > * of permissions that all pages have in common. Page addresses that do > * not have an associated enclave page are interpreted to zero > * permissions. > */ > > > +static unsigned long sgx_allowed_rwx(struct sgx_encl *encl, > > + struct vm_area_struct *vma) > > Suggestion for the name: sgx_calc_vma_prot_intersection() And have you thought off caching these results? I.e. hold the result for each VMA and only recalculate when the old value is dirty. Just a random thought, zero analysis but though that good to mention anyway. /Jarkko