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_PASS 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 87D32C43142 for ; Mon, 25 Jun 2018 09:22:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D7B6256A1 for ; Mon, 25 Jun 2018 09:22:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3D7B6256A1 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-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754933AbeFYJWA (ORCPT ); Mon, 25 Jun 2018 05:22:00 -0400 Received: from mga11.intel.com ([192.55.52.93]:58857 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754537AbeFYJV6 (ORCPT ); Mon, 25 Jun 2018 05:21:58 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 25 Jun 2018 02:21:58 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,269,1526367600"; d="scan'208";a="210901333" Received: from jsakkine-mobl1.tm.intel.com (HELO sfriis-mobl.ger.corp.intel.com) ([10.237.50.42]) by orsmga004.jf.intel.com with ESMTP; 25 Jun 2018 02:21:55 -0700 Message-ID: Subject: Re: [PATCH v11 09/13] x86, sgx: basic routines for enclave page cache From: Jarkko Sakkinen To: Sean Christopherson , x86@kernel.org, platform-driver-x86@vger.kernel.org Cc: dave.hansen@intel.com, nhorman@redhat.com, npmccallum@redhat.com, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , "open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , "open list:INTEL SGX" Date: Mon, 25 Jun 2018 12:21:55 +0300 In-Reply-To: <1529508365.9779.63.camel@intel.com> References: <20180608171216.26521-1-jarkko.sakkinen@linux.intel.com> <20180608171216.26521-10-jarkko.sakkinen@linux.intel.com> <1529508365.9779.63.camel@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.1-2 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2018-06-20 at 08:26 -0700, Sean Christopherson wrote: > > bool sgx_enabled __ro_after_init = false; > > EXPORT_SYMBOL(sgx_enabled); > > +bool sgx_lc_enabled __ro_after_init; > > +EXPORT_SYMBOL(sgx_lc_enabled); > > +atomic_t sgx_nr_free_pages = ATOMIC_INIT(0); > > +EXPORT_SYMBOL(sgx_nr_free_pages); > > +struct sgx_epc_bank sgx_epc_banks[SGX_MAX_EPC_BANKS]; > > +EXPORT_SYMBOL(sgx_epc_banks); > > +int sgx_nr_epc_banks; > > +EXPORT_SYMBOL(sgx_nr_epc_banks); > > +LIST_HEAD(sgx_active_page_list); > > +EXPORT_SYMBOL(sgx_active_page_list); > > +DEFINE_SPINLOCK(sgx_active_page_list_lock); > > +EXPORT_SYMBOL(sgx_active_page_list_lock); > > I don't think we should be exporting anything other than sgx_enabled > and sgx_lc_enabled. The only external use of a symbol that can't be > trivially (re)moved is in the driver's sgx_pm_suspend() in sgx_main.c, > which uses the sgx_active_page_list to invalidate enclaves. And that > behavior seems unsafe, e.g. an enclave could theoretically have zero > pages on the active list and so could be missed in the suspend flow. Fully agreed. Just forgotten cruft... /Jarkko