Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 20 Jul 2001 03:02:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 20 Jul 2001 03:02:17 -0400 Received: from [210.77.38.126] ([210.77.38.126]:16651 "EHLO ns.turbolinux.com.cn") by vger.kernel.org with ESMTP id ; Fri, 20 Jul 2001 03:02:06 -0400 Date: Wed, 4 Jul 2001 15:02:04 +0800 From: michaelc X-Mailer: The Bat! (v1.49) UNREG / CD5BF9353B3B7091 Reply-To: michaelc X-Priority: 3 (Normal) Message-ID: <1457128843.20010704150204@turbolinux.com.cn> To: "D. Stimits" CC: linux-kernel@vger.kernel.org Subject: Re: page reserved twice In-Reply-To: <3B42610F.29D004FF@idcomm.com> In-Reply-To: <3B42610F.29D004FF@idcomm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Original-Recipient: rfc822;linux-kernel-outgoing Hello D., Wednesday, July 04, 2001, 8:19:27 AM, you wrote: Wednesday, July 04, 2001, 8:19:27 AM, you wrote: DS> I'm curious if there is any significance to this, which occurs at each DS> reboot on an SMP system running noapic (sometimes Netscape manages to DS> produce a hard lockup on the system, sometimes a core dump indicates NS DS> had signal 7, bus error, in cases where it doesn't lock the system), DS> 2.4.6-pre1 with XFS patches: DS> kernel: BIOS-provided physical RAM map: DS> kernel: BIOS-e820: 0000000000000000 - 000000000009fc00 (usable) DS> kernel: BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved) DS> kernel: BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) DS> kernel: BIOS-e820: 0000000000100000 - 000000000ffe0000 (usable) DS> kernel: BIOS-e820: 000000000ffe0000 - 000000000fff8000 (ACPI data) DS> kernel: BIOS-e820: 000000000fff8000 - 0000000010000000 (ACPI NVS) DS> kernel: Scan SMP from c0000000 for 1024 bytes. DS> kernel: Scan SMP from c009fc00 for 1024 bytes. DS> kernel: Scan SMP from c00f0000 for 65536 bytes. DS> kernel: found SMP MP-table at 000faf50 DS> kernel: hm, page 000fa000 reserved twice. DS> kernel: hm, page 000fb000 reserved twice. DS> kernel: hm, page 000f4000 reserved twice. DS> thanteros kernel: hm, page 000f5000 reserved twice. DS> thanteros kernel: On node 0 totalpages: 65504 DS> thanteros kernel: zone(0): 4096 pages. DS> kernel: zone(1): 61408 pages. DS> kernel: zone(2): 0 pages. DS> kernel: Intel MultiProcessor Specification v1.1 DS> kernel: Virtual Wire compatibility mode. DS> kernel: OEM ID: _AMI_ Product ID: 840_CARMEL__ APIC at: 0xFEE00000 DS> Very similar messages seem to occur on a different machine with RH's DS> 2.4.2 kernel, BX chipset, and IO-APIC enabled. The machine this is from DS> has had this message on earlier kernels as well, none of which had XFS DS> patches. What is the significance (or consequence) of pages reserved DS> twice? I think that the message above doesn't matter with your nescape crash, When linux kernel boot, it reserve all usable low memory,for example kernel: BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved) kernel: BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) then kernel call find_smp_config to get MP configuration table if your machine is SMP, and the function will reserve the MP-table at 0xfa000,0xfb000, 0xf4000, and because these regions were reserved by kernel, so kernel would print the message, so it doesn't cause any problem on your machine. -- Best regards, michael chen mailto:michaelc@turbolinux.com.cn - 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/