From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755400Ab0HCI1b (ORCPT ); Tue, 3 Aug 2010 04:27:31 -0400 Received: from out01.mta.xmission.com ([166.70.13.231]:44616 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755125Ab0HCI12 (ORCPT ); Tue, 3 Aug 2010 04:27:28 -0400 To: Yinghai Lu Cc: Dave Airlie , LKML , Ingo Molnar Subject: Re: oops in ioapic_write_entry References: <4C577197.9020003@kernel.org> <4C57723C.1060400@kernel.org> <4C57C319.8070800@kernel.org> <4C57CCBB.1010608@kernel.org> From: ebiederm@xmission.com (Eric W. Biederman) Date: Tue, 03 Aug 2010 01:27:23 -0700 In-Reply-To: <4C57CCBB.1010608@kernel.org> (Yinghai Lu's message of "Tue\, 03 Aug 2010 01\:00\:59 -0700") Message-ID: User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-XM-SPF: eid=;;;mid=;;;hst=in01.mta.xmission.com;;;ip=67.188.4.80;;;frm=ebiederm@xmission.com;;;spf=neutral X-SA-Exim-Connect-IP: 67.188.4.80 X-SA-Exim-Mail-From: ebiederm@xmission.com X-SA-Exim-Scanned: No (on in01.mta.xmission.com); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Yinghai Lu writes: > On 08/03/2010 12:19 AM, Yinghai Lu wrote: >> On 08/02/2010 08:13 PM, Eric W. Biederman wrote: >>> Yinghai Lu writes: >>>> Index: linux-2.6/arch/x86/kernel/apic/io_apic.c >>>> =================================================================== >>>> --- linux-2.6.orig/arch/x86/kernel/apic/io_apic.c >>>> +++ linux-2.6/arch/x86/kernel/apic/io_apic.c >>>> @@ -1029,10 +1029,7 @@ static int pin_2_irq(int idx, int apic, >>>> } else { >>>> u32 gsi = mp_gsi_routing[apic].gsi_base + pin; >>>> >>>> - if (gsi >= NR_IRQS_LEGACY) >>>> - irq = gsi; >>>> - else >>>> - irq = gsi_top + gsi; >>>> + irq = gsi_to_irq(gsi); >>>> } >>>> >>>> #ifdef CONFIG_X86_32 >> >> what is the point for making irq = gsi_top + gsi when mptable is used instead of acpi? >> > > just tried those blind shifting gsi cause kernel with acpi crash in virtual box. What configuration did you try and had problems with? > [ 5.536000] querying PCI -> IRQ mapping bus:0, slot:11, pin:0. > [ 5.540000] ehci_hcd 0000:00:0b.0: can't find IRQ for PCI INT A; probably buggy MP table > [ I don't have a clue what the mpptable looks like in virtual box. My guess is that it is buggy and untested like so many mptables these days. > and on kvm it got: > [ 4.352280] e1000: Intel(R) PRO/1000 Network Driver - version 7.3.21-k6-NAPI > [ 4.356012] e1000: Copyright (c) 1999-2006 Intel Corporation. > [ 4.360120] querying PCI -> IRQ mapping bus:0, slot:3, pin:0. > [ 4.364006] PCI BIOS passed nonexistent PCI bus 0! > [ 4.368007] e1000 0000:00:03.0: can't find IRQ for PCI INT A; probably buggy MP table > [ 4.372049] e1000 0000:00:03.0: setting latency timer to 64 This example failed because mpparse said bus 0 was ISA. Which is a pretty bizarre thing to do, especially when bus 0 is pretty clearly PCI. That does sound like a buggy MP table. Eric