Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932159AbWBXBlV (ORCPT ); Thu, 23 Feb 2006 20:41:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932318AbWBXBlV (ORCPT ); Thu, 23 Feb 2006 20:41:21 -0500 Received: from mx1.redhat.com ([66.187.233.31]:9431 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S932159AbWBXBlU (ORCPT ); Thu, 23 Feb 2006 20:41:20 -0500 Date: Thu, 23 Feb 2006 20:41:12 -0500 From: Dave Jones To: ak@suse.de Cc: Linux Kernel Subject: Make SMP x86-64 kernels boot on more UP systems. Message-ID: <20060224014112.GA16089@redhat.com> Mail-Followup-To: Dave Jones , ak@suse.de, Linux Kernel Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1031 Lines: 28 Should someone boot an SMP kernel on UP hardware on some systems, strange things happen, such as.. SMP: Allowing 0 CPUs. We blow up shortly afterwards. Signed-off-by: Dave Jones --- linux-2.6.15.noarch/arch/x86_64/kernel/smpboot.c~ 2006-02-20 21:59:56.000000000 -0500 +++ linux-2.6.15.noarch/arch/x86_64/kernel/smpboot.c 2006-02-20 22:01:57.000000000 -0500 @@ -975,6 +975,11 @@ __init void prefill_possible_map(void) if (possible > NR_CPUS) possible = NR_CPUS; + if (possible == 0) { /* Could be SMP kernel on UP hw with broken BIOS */ + possible = 1; + printk (KERN_DEBUG "BIOS never enumerated boot CPU, fixing.\n"); + } + printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n", possible, max_t(int, possible - num_processors, 0)); - 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/