From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750749AbWGaLzr (ORCPT ); Mon, 31 Jul 2006 07:55:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750856AbWGaLzr (ORCPT ); Mon, 31 Jul 2006 07:55:47 -0400 Received: from pc1.pod.cz ([213.155.227.146]:22953 "EHLO pc11.op.pod.cz") by vger.kernel.org with ESMTP id S1750749AbWGaLzq (ORCPT ); Mon, 31 Jul 2006 07:55:46 -0400 Date: Mon, 31 Jul 2006 13:55:45 +0200 From: Vitezslav Samel To: linux-kernel@vger.kernel.org Subject: too low MAX_MP_BUSSES Message-ID: <20060731115545.GA3292@pc11.op.pod.cz> Mail-Followup-To: linux-kernel@vger.kernel.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! I tried upgrading our server (i386 arch) from 2.6.16 to 2.6.17 but there were some odd messages in dmesg: MP table busid value (32) for bustype ISA is too large, max. supported is 31 and (repeated 315 times): unknown bus type 32 I found out that 50% of the processor time was spent in softirq and the timers ran too fast. I didn't look for what else was wrong. Tracked down to this change in 2.6.17-rc2: diff -urN linux-2.6.17-rc1/arch/i386/kernel/mpparse.c linux-2.6.17-rc2/arch/i386/kernel/mpparse.c + if (m->mpc_busid >= MAX_MP_BUSSES) { + printk(KERN_WARNING "MP table busid value (%d) for bustype %s " + " is too large, max. supported is %d\n", + m->mpc_busid, str, MAX_MP_BUSSES - 1); + return; + } Uping the MAX_MP_BUSSES value in include/asm-i386/mach-default/mach_mpspec.h to 64 makes the machine work O.K. The system is HP DL380 g4 with 1 Xeon CPU, kernel compiled non-SMP. Here is excerpt from mptable output: --- Bus: Bus ID Type 0 PCI 1 PCI 2 PCI 3 PCI 4 PCI 5 PCI 6 PCI 10 PCI 32 ISA --- The last item is the offending one. Please, can you consider up the default value of MAX_MP_BUSSES? P.S.: also tested 2.6.18-rc3, the same - bad - result Cheers, Vita