From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760455Ab2EKOdY (ORCPT ); Fri, 11 May 2012 10:33:24 -0400 Received: from merlin.infradead.org ([205.233.59.134]:41616 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753549Ab2EKOdW convert rfc822-to-8bit (ORCPT ); Fri, 11 May 2012 10:33:22 -0400 Message-ID: <1336746790.1017.17.camel@twins> Subject: Re: Commit cb83b62 fails to boot with a divide by zero error. From: Peter Zijlstra To: Robin Holt Cc: Ingo Molnar , linux-kernel@vger.kernel.org Date: Fri, 11 May 2012 16:33:10 +0200 In-Reply-To: <20120511133938.GG3751@sgi.com> References: <20120511133938.GG3751@sgi.com> Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Mailer: Evolution 3.2.2- Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2012-05-11 at 08:39 -0500, Robin Holt wrote: > We found that reverting the commit: > cb83b62 (x86/sched/core) sched/numa: Rewrite the CONFIG_NUMA sched domain support > > also got things working. there's a particularly stupid bug in that code --- Subject: sched, numa: Fix the new NUMA topology bits From: Peter Zijlstra Date: Fri May 11 00:56:20 CEST 2012 There's no need to convert a node number to a node number by pretending its a cpu number.. Reported-by: Yinghai Lu Reported-and-Tested-by: Greg Pearson Signed-off-by: Peter Zijlstra --- kernel/sched/core.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6378,8 +6378,7 @@ static void sched_init_numa(void) sched_domains_numa_masks[i][j] = mask; for (k = 0; k < nr_node_ids; k++) { - if (node_distance(cpu_to_node(j), k) > - sched_domains_numa_distance[i]) + if (node_distance(j, k) > sched_domains_numa_distance[i]) continue; cpumask_or(mask, mask, cpumask_of_node(k));