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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, 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 C575BC4332D for ; Fri, 20 Mar 2020 19:50:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9745320739 for ; Fri, 20 Mar 2020 19:50:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="Tel2JQH6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726997AbgCTTuF (ORCPT ); Fri, 20 Mar 2020 15:50:05 -0400 Received: from hqnvemgate24.nvidia.com ([216.228.121.143]:14131 "EHLO hqnvemgate24.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726843AbgCTTuF (ORCPT ); Fri, 20 Mar 2020 15:50:05 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate24.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Fri, 20 Mar 2020 12:48:25 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Fri, 20 Mar 2020 12:50:04 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Fri, 20 Mar 2020 12:50:04 -0700 Received: from [10.2.57.131] (172.20.13.39) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Fri, 20 Mar 2020 19:50:04 +0000 Subject: Re: [PATCH] x86/mm: Make pud_present() check _PAGE_PROTNONE and _PAGE_PSE as well To: Anshuman Khandual , "Kirill A. Shutemov" CC: , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Dave Hansen , Andrew Morton , , , Dan Williams References: <1584507679-11976-1-git-send-email-anshuman.khandual@arm.com> <20200320114741.c62iolt2yzltnscf@box> <2e7a04cf-80cb-58c1-7344-2f8422ed7d31@arm.com> From: John Hubbard X-Nvconfidentiality: public Message-ID: <082aae4a-b190-7b54-eda9-0bbc28c8a6b3@nvidia.com> Date: Fri, 20 Mar 2020 12:50:03 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <2e7a04cf-80cb-58c1-7344-2f8422ed7d31@arm.com> X-Originating-IP: [172.20.13.39] X-ClientProxiedBy: HQMAIL107.nvidia.com (172.20.187.13) To HQMAIL107.nvidia.com (172.20.187.13) Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1584733705; bh=eMx7zJHblAy5+YXR6qnBGnBggweRnlFVeODh2DtisrU=; h=X-PGP-Universal:Subject:To:CC:References:From:X-Nvconfidentiality: Message-ID:Date:User-Agent:MIME-Version:In-Reply-To: X-Originating-IP:X-ClientProxiedBy:Content-Type:Content-Language: Content-Transfer-Encoding; b=Tel2JQH66ScF35HhrWYTgNQPP1AMRuVM4bvqwSSCBmgG15W1HzJ865N1Qi6NhkqsQ woGCQZujdfF6ZIip99vvJBaU5dDWbVtk8VH6TrI7rQ9NbZef+wNBXpkIRTVF22NV5O DdiyvOMXxmjF10pBRS25AJ0le5iUdr8U4HqAZQ1+mEp9OAH/lpnYZm8jqp0jtIKX8y 31/DhZyGPocZEe/XRi/zCkNQvP208imeKhlFzHwR1bTNk6xXX8xx/6zjJgtBRpjYV3 +um0XPIw+9MhAznV0GwYZZG9146hF/ek7V/WsEFcK+FNqBWLrJ3hk7tFHVapD37Wd0 NJivdmuFNik6Q== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/20/20 6:22 AM, Anshuman Khandual wrote: ... >>> +Cc: Kirill A. Shutemov >>> +Cc: Dan Williams >> >> Or we can just drop the pud_mknotpresent(). There's no users AFAICS and >> only x86 provides it. +1 > > Yes that will be an option but IMHO fixing pud_present() here might be > a better choice because, > > (1) pud_mknotpresent() with fixed pud_present() might be required later It might. Or it might not. Let's wait until it's actually used, and see. Dead code is an avoidable expense (adds size, space on the screen, email traffic and other wasted time), so let's avoid it here. > (2) PMD & PUD will be exact same (THP is supported on either level) > > Nonetheless, I am happy to go either way. > thanks, -- John Hubbard NVIDIA