Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964978AbXHOXft (ORCPT ); Wed, 15 Aug 2007 19:35:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760701AbXHOXfi (ORCPT ); Wed, 15 Aug 2007 19:35:38 -0400 Received: from shawidc-mo1.cg.shawcable.net ([24.71.223.10]:38574 "EHLO pd2mo3so.prod.shaw.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761783AbXHOXfh (ORCPT ); Wed, 15 Aug 2007 19:35:37 -0400 Date: Wed, 15 Aug 2007 17:35:14 -0600 From: Robert Hancock Subject: Re: dual Xeon hyperthread system only showing up as 2 cpus In-reply-to: To: Chris Friesen Cc: linux-kernel@vger.kernel.org Message-id: <46C38DB2.9040400@shaw.ca> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit References: User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1675 Lines: 53 Chris Friesen wrote: > > Hi all, > > I've got a system that has two hyperthread-capable Xeons. If I boot it > with 2.6.10 it shows up as 4 cpus, but with 2.6.14 it only shows 2 cpus. > > The relevent boot logs are: > > 2.6.10: > > DMI 2.3 present. > ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled) > Processor #0 15:2 APIC version 20 > ACPI: LAPIC (acpi_id[0x02] lapic_id[0x06] enabled) > Processor #6 15:2 APIC version 20 > ACPI: LAPIC (acpi_id[0x03] lapic_id[0x01] enabled) > Processor #1 15:2 APIC version 20 > ACPI: LAPIC (acpi_id[0x04] lapic_id[0x07] enabled) > Processor #7 15:2 APIC version 20 > Using ACPI for processor (LAPIC) configuration information > Intel MultiProcessor Specification v1.4 > Virtual Wire compatibility mode. > > Processors: 4 > > > 2.6.14: > > DMI 2.3 present. > Intel MultiProcessor Specification v1.4 > Virtual Wire compatibility mode. > OEM ID: INTEL Product ID: KingsCanyonC APIC at: 0xFEE00000 > Processor #0 15:2 APIC version 20 > Processor #6 15:2 APIC version 20 > > Processors: 2 You snipped the important part of the log. It's not using ACPI in 2.6.14 for some reason, which you need for HT to be detected. Either you didn't configure it in or it's failed to enable somehow. Please post the entire dmesg. -- Robert Hancock Saskatoon, SK, Canada To email, remove "nospam" from hancockr@nospamshaw.ca Home Page: http://www.roberthancock.com/ - 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/