Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756059Ab2EYV7L (ORCPT ); Fri, 25 May 2012 17:59:11 -0400 Received: from terminus.zytor.com ([198.137.202.10]:44157 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753656Ab2EYV7J (ORCPT ); Fri, 25 May 2012 17:59:09 -0400 Message-ID: <4FC0009C.5000704@zytor.com> Date: Fri, 25 May 2012 14:58:52 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: Bjorn Helgaas CC: Yinghai Lu , Linus Torvalds , Steven Newbury , Andrew Morton , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 02/11] PCI: Try to allocate mem64 above 4G at first References: <1337754877-19759-1-git-send-email-yinghai@kernel.org> <1337754877-19759-3-git-send-email-yinghai@kernel.org> <20120525043651.GA1391@google.com> <20120525193716.GA8817@google.com> In-Reply-To: X-Enigmail-Version: 1.4.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1197 Lines: 30 On 05/25/2012 02:55 PM, Bjorn Helgaas wrote: > > I think we actually have a separate bug here. On 64-bit non-x86 > architectures, PCIBIOS_MAX_MEM_32 is a 64-bit -1, so the following > attempt to avoid putting a 32-bit BAR above 4G only works on x86, > where PCIBIOS_MAX_MEM_32 is 0xffffffff. > > /* don't allocate too high if the pref mem doesn't support 64bit*/ > if (!(res->flags & IORESOURCE_MEM_64)) > max = PCIBIOS_MAX_MEM_32; > > I think we should fix this with a separate patch that removes > PCIBIOS_MAX_MEM_32 altogether, replacing this use with an explicit > 0xffffffff (or some other "max 32-bit value" symbol). I don't think > there's anything arch-specific about this. > > So I'd like to see two patches here: > 1) Avoid allocating 64-bit regions for 32-bit BARs > 2) Try to allocate regions above 4GB for 64-bit BARs > Do we also need to track the maximum address available to the CPU? -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/