Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752310Ab0AIKKs (ORCPT ); Sat, 9 Jan 2010 05:10:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751580Ab0AIKKr (ORCPT ); Sat, 9 Jan 2010 05:10:47 -0500 Received: from e38.co.us.ibm.com ([32.97.110.159]:44575 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750786Ab0AIKKq (ORCPT ); Sat, 9 Jan 2010 05:10:46 -0500 Date: Sat, 9 Jan 2010 15:40:38 +0530 From: Ananth N Mavinakayanahalli To: suresh.b.siddha@intel.com, Linus Torvalds Cc: yinghai@kernel.org, Ingo Molnar , lkml , stable@kernel.org Subject: [PATCH] Make Intel 8-way Xeons boot again Message-ID: <20100109101038.GA17555@in.ibm.com> Reply-To: ananth@in.ibm.com MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1321 Lines: 35 On an 8-way system with Intel Xeon X7350 CPUs, booting 2.6.32 or newer kernels fails at: ... CPU0: Intel(R) Xeon(R) CPU X7350 @ 2.93GHz stepping 0b Booting Node 0, Processors #1 #2 #3 #4 #5 #6 #7 Ok. Brought up 8 CPUs Total of 8 processors activated (46906.05 BogoMIPS). Git bisect showed 2fbd07a5f as the offending commit. With the patch below, I am able to boot the latest Linus' git tree on the machine. If this patch is correct, it needs to get into the stable tree too. Signed-off-by: Ananth N Mavinakayanahalli --- Index: linux-2.6/arch/x86/kernel/apic/probe_64.c =================================================================== --- linux-2.6.orig/arch/x86/kernel/apic/probe_64.c 2010-01-09 14:54:29.000000000 +0530 +++ linux-2.6/arch/x86/kernel/apic/probe_64.c 2010-01-09 14:57:53.000000000 +0530 @@ -70,7 +70,7 @@ if (apic == &apic_flat) { switch (boot_cpu_data.x86_vendor) { case X86_VENDOR_INTEL: - if (num_processors > 8) + if (num_processors >= 8) apic = &apic_physflat; break; case X86_VENDOR_AMD: -- 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/