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=-2.3 required=3.0 tests=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 5AA3BC432C0 for ; Tue, 26 Nov 2019 21:48:38 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 09AF02064B for ; Tue, 26 Nov 2019 21:48:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 09AF02064B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 47MyFv75X7zDqnv for ; Wed, 27 Nov 2019 08:48:35 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=arm.com (client-ip=217.140.110.172; helo=foss.arm.com; envelope-from=robin.murphy@arm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lists.ozlabs.org (Postfix) with ESMTP id 47MyBR6m1GzDqmh for ; Wed, 27 Nov 2019 08:45:33 +1100 (AEDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 59F5431B; Tue, 26 Nov 2019 13:45:31 -0800 (PST) Received: from [192.168.1.124] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 37D3B3F52E; Tue, 26 Nov 2019 13:45:26 -0800 (PST) Subject: Re: [PATCH v2] dma-mapping: treat dev->bus_dma_mask as a DMA limit To: Nicolas Saenz Julienne , Christoph Hellwig , Nathan Chancellor References: <20191121092646.8449-1-nsaenzjulienne@suse.de> <20191123165108.GA15306@ubuntu-x2-xlarge-x86> <20191125074412.GA30595@lst.de> <0b851d0e-37c7-062e-c287-05f8c8a54c16@arm.com> <45feed391bbd95c46f64b31cf8817d4f773c8da1.camel@suse.de> From: Robin Murphy Message-ID: <935d65b4-a28e-d7b9-7392-42fec71b5150@arm.com> Date: Tue, 26 Nov 2019 21:45:19 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:68.0) Gecko/20100101 Thunderbird/68.2.1 MIME-Version: 1.0 In-Reply-To: <45feed391bbd95c46f64b31cf8817d4f773c8da1.camel@suse.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Zijlstra , Dave Hansen , linux-mips@vger.kernel.org, linux-ide@vger.kernel.org, Paul Mackerras , "H. Peter Anvin" , Frank Rowand , Marek Szyprowski , Lorenzo Pieralisi , Paul Burton , Joerg Roedel , x86@kernel.org, linux-acpi@vger.kernel.org, Ingo Molnar , linux-pci@vger.kernel.org, James Hogan , Len Brown , devicetree@vger.kernel.org, Rob Herring , Borislav Petkov , Andy Lutomirski , Bjorn Helgaas , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Jens Axboe , "Rafael J. Wysocki" , Hanjun Guo , linux-kernel@vger.kernel.org, Ralf Baechle , iommu@lists.linux-foundation.org, Sudeep Holla , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 2019-11-26 6:51 pm, Nicolas Saenz Julienne wrote: > On Mon, 2019-11-25 at 16:33 +0000, Robin Murphy wrote: >> On 25/11/2019 7:44 am, Christoph Hellwig wrote: >>> On Sat, Nov 23, 2019 at 09:51:08AM -0700, Nathan Chancellor wrote: >>>> Just as an FYI, this introduces a warning on arm32 allyesconfig for me: >>> >>> I think the dma_limit argument to iommu_dma_alloc_iova should be a u64 >>> and/or we need to use min_t and open code the zero exception. >>> >>> Robin, Nicolas - any opinions? >> >> Yeah, given that it's always held a mask I'm not entirely sure why it >> was ever a dma_addr_t rather than a u64. Unless anyone else is desperate >> to do it I'll get a cleanup patch ready for rc1. > > Sounds good to me too > > Robin, since I started the mess, I'll be happy to do it if it helps offloading > some work from you. No worries - your change only exposed my original weird decision ;) On second look the patch was literally a trivial one-liner, so I've written it up already. Cheers, Robin.