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=-1.0 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 52A70C43381 for ; Mon, 4 Mar 2019 12:01:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 17C6C20645 for ; Mon, 4 Mar 2019 12:01:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726100AbfCDMBo (ORCPT ); Mon, 4 Mar 2019 07:01:44 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:60774 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725974AbfCDMBo (ORCPT ); Mon, 4 Mar 2019 07:01:44 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 73ED6A78; Mon, 4 Mar 2019 04:01:43 -0800 (PST) Received: from [10.1.196.69] (e112269-lin.cambridge.arm.com [10.1.196.69]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A32AD3F703; Mon, 4 Mar 2019 04:01:39 -0800 (PST) Subject: Re: [PATCH v3 05/34] c6x: mm: Add p?d_large() definitions To: "Kirill A. Shutemov" Cc: Mark Rutland , Peter Zijlstra , Catalin Marinas , Dave Hansen , Will Deacon , linux-mm@kvack.org, "H. Peter Anvin" , "Liang, Kan" , linux-c6x-dev@linux-c6x.org, x86@kernel.org, Ingo Molnar , Mark Salter , Arnd Bergmann , Aurelien Jacquiot , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Borislav Petkov , Andy Lutomirski , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Ard Biesheuvel , linux-kernel@vger.kernel.org, James Morse References: <20190227170608.27963-1-steven.price@arm.com> <20190227170608.27963-6-steven.price@arm.com> <20190301214851.ucems2icwt64iabx@kshutemo-mobl1> From: Steven Price Message-ID: Date: Mon, 4 Mar 2019 12:01:37 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.0 MIME-Version: 1.0 In-Reply-To: <20190301214851.ucems2icwt64iabx@kshutemo-mobl1> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/03/2019 21:48, Kirill A. Shutemov wrote: > On Wed, Feb 27, 2019 at 05:05:39PM +0000, Steven Price wrote: >> walk_page_range() is going to be allowed to walk page tables other than >> those of user space. For this it needs to know when it has reached a >> 'leaf' entry in the page tables. This information is provided by the >> p?d_large() functions/macros. >> >> For c6x there's no MMU so there's never a large page, so just add stubs. > > Other option would be to provide the stubs via generic headers form !MMU. > I agree that could be done, but equally the definitions of p?d_present/p?d_none/p?d_bad etc could be provided by a generic header for !MMU but currently are not. It makes sense to keep the p?d_large definitions next to the others. I'd prefer to stick with a (relatively) small change here - it's already quite a long series! But this is certainly something that could be tidied up for !MMU archs. Steve