From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763988AbXHPSm6 (ORCPT ); Thu, 16 Aug 2007 14:42:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755423AbXHPSms (ORCPT ); Thu, 16 Aug 2007 14:42:48 -0400 Received: from mail.suse.de ([195.135.220.2]:35854 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755898AbXHPSmr (ORCPT ); Thu, 16 Aug 2007 14:42:47 -0400 Date: Thu, 16 Aug 2007 21:36:49 +0200 From: Andi Kleen To: Len Brown Cc: Andi Kleen , linux-acpi@vger.kernel.org, Linux Kernel Mailing List Subject: Re: [PATCH] ACPI: boot correctly with "nosmp" or "maxcpus=0" Message-ID: <20070816193649.GA16680@bingen.suse.de> References: <200708160332.30732.lenb@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200708160332.30732.lenb@kernel.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > @@ -157,10 +162,13 @@ early_param("nosmp", nosmp); > static int __init maxcpus(char *str) > { > get_option(&str, &max_cpus); > - return 1; > + if (max_cpus == 0) > + disable_ioapic_setup(); I must say I never liked that maxcpus=0 ... does disable the APIC too. There can be situations where you want only a single CPU, but still full APICs because modern systems don't boot without. It's the old traditional documented semantics though, but on the other hand if it never worked with ACPI i guess people are not relying on it. So perhaps it would be better to change that? Or add a new option to limit CPUs without disabling ACPIC? -Andi