Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763776AbYHFDPl (ORCPT ); Tue, 5 Aug 2008 23:15:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751186AbYHFDPc (ORCPT ); Tue, 5 Aug 2008 23:15:32 -0400 Received: from rv-out-0506.google.com ([209.85.198.233]:47334 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751054AbYHFDPb (ORCPT ); Tue, 5 Aug 2008 23:15:31 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:mime-version:content-type :content-transfer-encoding:content-disposition; b=kqXInbz5uQLW0KZgz30CG+oZtUGVVDLgrIfnzFX1jGF12+l/lllc39s/lcodasgN/P 5lAxcob6/G5ZqRa5l/cLNxNAGjgZrdcFU7IZsptQOk8GikDfzRGtxLMCeXl8c6wV6Tfi X0ExpueuYMCAoRD6oB/eq6mOHb5+bEncvHlWA= Message-ID: Date: Wed, 6 Aug 2008 11:15:30 +0800 From: "Jeff Chua" To: lkml Subject: 2.6.27rc1 cannot boot more than 8CPUs MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1835 Lines: 51 I've a Dell R900 with 4 quad-core Xeon processors (total 16CPUs), but can only managed to boot up with CONFIG_NR_CPUS=8. Setting CONFIG_NR_CPUS=16 causes the kernel to hang while booting. Here's the dmesg with CONFIG_NR_CPUS=8 ... CPU6: Intel(R) Xeon(R) CPU L7345 @ 1.86GHz stepping 0b checking TSC synchronization [CPU#0 -> CPU#6]: passed. CPU 7 irqstacks, hard=c0526000 soft=c051e000 Booting processor 7/26 ip 6000 Initializing CPU#7 Calibrating delay using timer specific routine.. 3723.85 BogoMIPS (lpj=7447700) CPU: L1 I cache: 32K, L1 D cache: 32K CPU: L2 cache: 4096K CPU: Physical Processor ID: 6 CPU: Processor Core ID: 2 x86 PAT enabled: cpu 7, old 0x7040600070406, new 0x7010600070106 CPU7: Intel(R) Xeon(R) CPU L7345 @ 1.86GHz stepping 0b checking TSC synchronization [CPU#0 -> CPU#7]: passed. Brought up 8 CPUs Total of 8 processors activated (29790.71 BogoMIPS). net_namespace: 596 bytes Booting paravirtualized kernel on bare hardware NET: Registered protocol family 16 Here's the dmesg with CONFIG_NR_CPUS=16 ... Booting processor 8/1 ip 6000 Initializing CPU#8 Calibrating delay using timer specific routine.. 3723.85 BogoMIPS (lpj=7447793) CPU: L1 I cache: 32K, L1 D cache: 32K CPU: L2 cache: 4096K CPU: Physical Processor ID: 0 CPU: Processor Core ID: 1 x86 PAT enabled: cpu 7, old 0x7040600070406, new 0x7010600070106 CPU8: Intel(R) Xeon(R) CPU L7345 @ 1.86GHz stepping 0b checking TSC synchronization [CPU#0 -> CPU#8]: passed. *** Hangs here *** How can I debug this further? I'm using the latest linux git pull. Thanks, Jeff. -- 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/