Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754807AbZDRJPg (ORCPT ); Sat, 18 Apr 2009 05:15:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752682AbZDRJP1 (ORCPT ); Sat, 18 Apr 2009 05:15:27 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:52069 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752621AbZDRJP0 (ORCPT ); Sat, 18 Apr 2009 05:15:26 -0400 Date: Sat, 18 Apr 2009 11:15:09 +0200 From: Ingo Molnar To: Yinghai Lu Cc: Jesse Barnes , Matthew Wilcox , linux-pci@vger.kernel.org, "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 2/3] pci: don't assume pref memio are 64bit -v2 Message-ID: <20090418091509.GM7678@elte.hu> References: <49E992C2.4010707@kernel.org> <49E99303.50004@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <49E99303.50004@kernel.org> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2748 Lines: 53 * Yinghai Lu wrote: > one system with 4g installed ( there is 1g hole) > > when 4G installed. > BIOS put ACPI etc need the hole > [ 0.000000] BIOS-provided physical RAM map: > [ 0.000000] BIOS-e820: 0000000000000000 - 000000000009bc00 (usable) > [ 0.000000] BIOS-e820: 000000000009bc00 - 00000000000a0000 (reserved) > [ 0.000000] BIOS-e820: 00000000000e3000 - 0000000000100000 (reserved) > [ 0.000000] BIOS-e820: 0000000000100000 - 00000000bffa0000 (usable) > [ 0.000000] BIOS-e820: 00000000bffa0000 - 00000000bffae000 (ACPI data) > [ 0.000000] BIOS-e820: 00000000bffae000 - 00000000bfff0000 (ACPI NVS) > [ 0.000000] BIOS-e820: 00000000bfff0000 - 00000000c0000000 (reserved) > [ 0.000000] BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved) > [ 0.000000] BIOS-e820: 00000000ffb00000 - 0000000100000000 (reserved) > [ 0.000000] BIOS-e820: 0000000100000000 - 0000000140000000 (usable) > so in kernel resource will be reserved for 0xbffa0000 - 0xbfff0000 for ACPI > 0x100000 - 0xbffa0000 for RAM... btw., sidenote, it would be nice to enhance the e820 table printout with size and hole info as well. I did this manually yesterday in another mail: BIOS-provided physical RAM map: BIOS-e820: 0000000000000000 - 000000000009fc00 (usable) 0.639 MB RAM BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved) 0.001 MB [ hole ] 0.250 MB BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) 0.125 MB BIOS-e820: 0000000000100000 - 000000003ed94000 (usable) 1004.5 MB RAM BIOS-e820: 000000003ed94000 - 000000003ee4e000 (ACPI NVS) 0.7 MB BIOS-e820: 000000003ee4e000 - 000000003fea2000 (usable) 16.3 MB RAM BIOS-e820: 000000003fea2000 - 000000003fee9000 (ACPI NVS) 0.3 MB BIOS-e820: 000000003fee9000 - 000000003feed000 (usable) 0.15 MB RAM BIOS-e820: 000000003feed000 - 000000003feff000 (ACPI data 0.07 MB BIOS-e820: 000000003feff000 - 000000003ff00000 (usable) 0.004 MB RAM [ hole ] 1.0 MB [ hole ] 3072.0 MB it would be extremely useful to have that in the printout, to see the physical address space layout at a glance. Small holes are easy to miss, and e820 entry sizes are hard to judge at a glance. To make this fit well, i'd suggest to drop the 'BIOS-e820: ' prefix - it's redundant. Ingo -- 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/