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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,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 0C0C2C0018C for ; Thu, 3 Dec 2020 15:57:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AE845207AE for ; Thu, 3 Dec 2020 15:57:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388407AbgLCP5d (ORCPT ); Thu, 3 Dec 2020 10:57:33 -0500 Received: from mga03.intel.com ([134.134.136.65]:37124 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387665AbgLCP5c (ORCPT ); Thu, 3 Dec 2020 10:57:32 -0500 IronPort-SDR: POaqQrNEu1R/xqUCFxYZViCqgp3vAy4i7gAw0+3dTVRe8xMIKqgHBXvsXd17x2jWMEGx949qR8 6hihZFcZvR6Q== X-IronPort-AV: E=McAfee;i="6000,8403,9824"; a="173309989" X-IronPort-AV: E=Sophos;i="5.78,389,1599548400"; d="scan'208";a="173309989" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Dec 2020 07:56:52 -0800 IronPort-SDR: QTXfd0UHBF2xxeJDIPK47vgt29cm5V2RiGcTsfVJv4BzxpNEjVu0qx77u4M0SX02qmWYZpZdGW iEBaSxNFZ05g== X-IronPort-AV: E=Sophos;i="5.78,389,1599548400"; d="scan'208";a="550534058" Received: from sshellma-mobl.amr.corp.intel.com (HELO [10.212.138.60]) ([10.212.138.60]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Dec 2020 07:56:50 -0800 Subject: Re: [PATCH v15 06/26] x86/mm: Change _PAGE_DIRTY to _PAGE_DIRTY_HW To: Dave Hansen , Borislav Petkov Cc: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , Weijiang Yang , Pengfei Xu References: <20201110162211.9207-1-yu-cheng.yu@intel.com> <20201110162211.9207-7-yu-cheng.yu@intel.com> <20201203091910.GE3059@zn.tnic> <93eb0255-df5c-5cb3-654f-e74c1af956b2@intel.com> From: "Yu, Yu-cheng" Message-ID: <585009b4-537e-0fc9-ea4a-79210c96a514@intel.com> Date: Thu, 3 Dec 2020 07:56:49 -0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.12.1 MIME-Version: 1.0 In-Reply-To: <93eb0255-df5c-5cb3-654f-e74c1af956b2@intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On 12/3/2020 7:12 AM, Dave Hansen wrote: > On 12/3/20 1:19 AM, Borislav Petkov wrote: >> On Tue, Nov 10, 2020 at 08:21:51AM -0800, Yu-cheng Yu wrote: >>> Before introducing _PAGE_COW for non-hardware memory management purposes in >>> the next patch, rename _PAGE_DIRTY to _PAGE_DIRTY_HW and _PAGE_BIT_DIRTY to >>> _PAGE_BIT_DIRTY_HW to make meanings more clear. There are no functional >>> changes from this patch. >> There's no guarantee for "next" or "this" patch when a patch gets >> applied so reword your commit message pls. >> >> Also, I fail to understand here what _PAGE_DIRTY_HW makes more clear? >> The page dirty bit is clear enough to me so why the churn? > > Once upon a time in this set, we had: > > _PAGE_DIRTY (the old hardware bit) > and > _PAGE_DIRTY_SW (the new shadow stack necessitated bit) > > In *that* case, it made sense to change the name of the hardware one to > help differentiate them. But, over time, we changed _PAGE_DIRTY_SW to > _PAGE_COW. > > I think you're right. The renaming is just churn now with the current > naming. > Ok, I will drop this patch.