From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262412AbVAKDse (ORCPT ); Mon, 10 Jan 2005 22:48:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262426AbVAKDrq (ORCPT ); Mon, 10 Jan 2005 22:47:46 -0500 Received: from fw.osdl.org ([65.172.181.6]:56222 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S262412AbVAKDpq (ORCPT ); Mon, 10 Jan 2005 22:45:46 -0500 Message-ID: <41E34A51.3080005@osdl.org> Date: Mon, 10 Jan 2005 19:38:57 -0800 From: "Randy.Dunlap" User-Agent: Mozilla Thunderbird 0.9 (X11/20041103) X-Accept-Language: en-us, en MIME-Version: 1.0 To: William Lee Irwin III CC: Linus Torvalds , Dave , linux-kernel@vger.kernel.org, smaurer@teja.com, linux@arm.linux.org.uk, dsaxena@plexity.net, drew.moseley@intel.com Subject: Re: clean way to support >32bit addr on 32bit CPU References: <8746466a050110153479954fd2@mail.gmail.com> <41E31D95.50205@osdl.org> <20050111020550.GE2696@holomorphy.com> In-Reply-To: <20050111020550.GE2696@holomorphy.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org William Lee Irwin III wrote: > On Mon, Jan 10, 2005 at 05:30:25PM -0800, Linus Torvalds wrote: > >>I don't think ioaddr_t needs to match resources. None of the IO accessor >>functions take "u64"s anyway - and aren't likely to do so in the future >>either - so "unsigned long" should be good enough. >>Having u64 for resource handling is mainly an issue for RAM and >>memory-mapped IO (right now the 32-bit limit means that we throw away >>information about stuff above the 4GB mark from the e820 interfaces on >>x86, for example - that _happens_ to work because we never see anything >>but RAM there anyway, but it means that /proc/iomem doesn't show all of >>the system RAM, and it does mean that our resource management doesn't >>actually handle 64-bit addresses correctly. >>See drivers/pci/probe.c for the result: >> "PCI: Unable to handle 64-bit address for device xxxx" >>(and I do not actually think this has _ever_ happened in real life, which >>makes me suspect that Windows doesn't handle them either - but it >>inevitably will happen some day). > > > I have a vague recollection of seeing a report of an ia32 device and/or > machine with this property from John Fusco but am having a tough time > searching the archives properly for it. I do recall it being around the > time the remap_pfn_range() work was started, and I also claimed it as > one of the motivators of it in one of my posts. I'm unaware of whether > there are more general resources in John Fusco's situation. > > My follow-ups began with: > Message-ID: <20040924021735.GL9106@holomorphy.com> > References: <41535AAE.6090700@yahoo.com> http://marc.theaimsgroup.com/?l=linux-mm&m=109598180125156&w=2 -- ~Randy