From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759585Ab1CDObu (ORCPT ); Fri, 4 Mar 2011 09:31:50 -0500 Received: from hera.kernel.org ([140.211.167.34]:49762 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753267Ab1CDObt (ORCPT ); Fri, 4 Mar 2011 09:31:49 -0500 Date: Fri, 4 Mar 2011 14:31:15 GMT From: tip-bot for Yinghai Lu Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, yinghai@kernel.org, tj@kernel.org, tglx@linutronix.de, rientjes@google.com, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, yinghai@kernel.org, tj@kernel.org, tglx@linutronix.de, rientjes@google.com, mingo@elte.hu In-Reply-To: <4D6ECF72.5010308@kernel.org> References: <4D6ECF72.5010308@kernel.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] x86, numa: Fix numa_emulation code with memory-less node0 Message-ID: Git-Commit-ID: 3b28cf32cc32594710590685ee478f697ed4f328 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Fri, 04 Mar 2011 14:31:16 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 3b28cf32cc32594710590685ee478f697ed4f328 Gitweb: http://git.kernel.org/tip/3b28cf32cc32594710590685ee478f697ed4f328 Author: Yinghai Lu AuthorDate: Wed, 2 Mar 2011 15:14:58 -0800 Committer: Ingo Molnar CommitDate: Fri, 4 Mar 2011 15:20:19 +0100 x86, numa: Fix numa_emulation code with memory-less node0 This crash happens on a system that does not have RAM on node0. When numa_emulation is compiled in, and: 1. we boot the system without numa=fake... 2. or we boot the system with numa=fake=128 to make emulation fail we will get: [ 0.076025] ------------[ cut here ]------------ [ 0.080004] kernel BUG at arch/x86/mm/numa_64.c:788! [ 0.080004] invalid opcode: 0000 [#1] SMP [...] need to use early_cpu_to_node() directly, because cpu_to_apicid and apicid_to_node will return node0 that is not onlined. Signed-off-by: Yinghai Lu Acked-by: Tejun Heo Cc: David Rientjes LKML-Reference: <4D6ECF72.5010308@kernel.org> Signed-off-by: Ingo Molnar --- arch/x86/mm/numa_64.c | 6 +----- 1 files changed, 1 insertions(+), 5 deletions(-) diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c index 95ea155..1337c51 100644 --- a/arch/x86/mm/numa_64.c +++ b/arch/x86/mm/numa_64.c @@ -780,11 +780,7 @@ void __cpuinit numa_add_cpu(int cpu) int physnid; int nid = NUMA_NO_NODE; - apicid = early_per_cpu(x86_cpu_to_apicid, cpu); - if (apicid != BAD_APICID) - nid = apicid_to_node[apicid]; - if (nid == NUMA_NO_NODE) - nid = early_cpu_to_node(cpu); + nid = early_cpu_to_node(cpu); BUG_ON(nid == NUMA_NO_NODE || !node_online(nid)); /*