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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03268C433F5 for ; Thu, 28 Apr 2022 15:48:15 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 728E08D0001; Thu, 28 Apr 2022 11:48:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6D99F6B00AF; Thu, 28 Apr 2022 11:48:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 59F768D0001; Thu, 28 Apr 2022 11:48:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.25]) by kanga.kvack.org (Postfix) with ESMTP id 47A566B00AE for ; Thu, 28 Apr 2022 11:48:15 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay13.hostedemail.com (Postfix) with ESMTP id 1C2EF62287 for ; Thu, 28 Apr 2022 15:48:15 +0000 (UTC) X-FDA: 79406719350.15.A5D4092 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf08.hostedemail.com (Postfix) with ESMTP id 148F6160055 for ; Thu, 28 Apr 2022 15:48:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=XOgwq5eoTTCPAfsOlyGMB7z+MPxPVXV6EHeT3BNE4Zg=; b=13L3/8xfYd5r7ei2jQ2e3XNKaR 93LNWcgplTRQRfntmFheSDUHevjhCvG2wQLWO4Vf0fMQcZYYfXs6abIgZi+e+zXCpOFfRck1Lyjky F3XQANxUWkD4ipLofM72Oi2X4hmlt3cQ+8BleKnToAJ9HMW0/6srAQLIihIBG3bxwcTgpdF3IBls7 b36uluoLcRXe0IqTMR6N62BxTqX4LASnHi2rMTL/ILd5+kTqno5L67DwRWsbNG6LGmQNEchUmAijY yQnB7Wc4pfk+PWSjoNYbBhCQjxzxg5/x+7T1WJdc8OHAAcG6730cW927P6E41k+RdYPKlBg1wT0BC HxI+VbhQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nk6NF-007j0b-4F; Thu, 28 Apr 2022 15:48:09 +0000 Date: Thu, 28 Apr 2022 08:48:09 -0700 From: Christoph Hellwig To: Will Deacon Cc: Kefeng Wang , Catalin Marinas , Andrew Morton , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 0/4] arm64: Cleanup ioremap() and support ioremap_prot() Message-ID: References: <20220427121413.168468-1-wangkefeng.wang@huawei.com> <20220428104612.GA14515@willie-the-truck> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220428104612.GA14515@willie-the-truck> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b="13L3/8xf"; dmarc=none; spf=none (imf08.hostedemail.com: domain of BATV+662a636c1b7b18200861+6822+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+662a636c1b7b18200861+6822+infradead.org+hch@bombadil.srs.infradead.org X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 148F6160055 X-Rspam-User: X-Stat-Signature: jxwsm734sfecsi5id618qetc8qkb3gqb X-HE-Tag: 1651160887-144489 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Apr 28, 2022 at 11:46:12AM +0100, Will Deacon wrote: > That's not a massively compelling diffstat for a cleanup, in all honesty. > I looked at generic_access_phys() to try to figure out why we would want > that on arm64, but it seems like it's related to mmap() of devices in > userspace. Bearing in mind that CONFIG_STRICT_DEVMEM=y by default, please > can you justify why this is something worth doing? While I don't care much about ioremap_prot I'd really love to eventually convert everyone to the common ioremap code as there really is no point in duplicating it in the architectures.