From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756107AbYKDShB (ORCPT ); Tue, 4 Nov 2008 13:37:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752528AbYKDSgx (ORCPT ); Tue, 4 Nov 2008 13:36:53 -0500 Received: from smarthost02.mail.zen.net.uk ([212.23.3.141]:38521 "EHLO smarthost02.mail.zen.net.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752123AbYKDSgw (ORCPT ); Tue, 4 Nov 2008 13:36:52 -0500 Subject: Re: [PATCH] x86: Don't allow nr_irqs > NR_IRQS From: Ben Hutchings To: Cyrill Gorcunov Cc: Thomas Gleixner , linux-kernel@vger.kernel.org, Yinghai Lu In-Reply-To: <20081104180012.GG21470@localhost> References: <1225819102.3074.15.camel@achroite> <20081104180012.GG21470@localhost> Content-Type: text/plain; charset=utf-8 Organization: Solarflare Communications Date: Tue, 04 Nov 2008 18:36:47 +0000 Message-Id: <1225823807.3074.24.camel@achroite> Mime-Version: 1.0 X-Mailer: Evolution 2.22.1 (2.22.1-2.fc9) Content-Transfer-Encoding: 8bit X-Originating-Smarthost02-IP: [82.69.137.158] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2008-11-04 at 21:00 +0300, Cyrill Gorcunov wrote: [...] > | I hit this when running net-next-2.6 (close to 2.6.28-rc3) on a > | Supermicro dual Xeon system. NR_IRQS is 224 but probe_nr_irqs() detects > | 5 IOAPICs (!) and returns 240. Here are the log messages: > | > | Tue Nov 4 16:53:47 2008 ACPI: IOAPIC (id[0x01] address[0xfec00000] gsi_base[0]) > | Tue Nov 4 16:53:47 2008 IOAPIC[0]: apic_id 1, version 32, address 0xfec00000, GSI 0-23 > | Tue Nov 4 16:53:47 2008 ACPI: IOAPIC (id[0x02] address[0xfec81000] gsi_base[24]) > | Tue Nov 4 16:53:47 2008 IOAPIC[1]: apic_id 2, version 32, address 0xfec81000, GSI 24-47 > | Tue Nov 4 16:53:47 2008 ACPI: IOAPIC (id[0x03] address[0xfec81400] gsi_base[48]) > | Tue Nov 4 16:53:47 2008 IOAPIC[2]: apic_id 3, version 32, address 0xfec81400, GSI 48-71 > | Tue Nov 4 16:53:47 2008 ACPI: IOAPIC (id[0x04] address[0xfec82000] gsi_base[72]) > | Tue Nov 4 16:53:47 2008 IOAPIC[3]: apic_id 4, version 32, address 0xfec82000, GSI 72-95 > | Tue Nov 4 16:53:47 2008 ACPI: IOAPIC (id[0x05] address[0xfec82400] gsi_base[96]) > | Tue Nov 4 16:53:47 2008 IOAPIC[4]: apic_id 5, version 32, address 0xfec82400, GSI 96-119 > | Tue Nov 4 16:53:47 2008 ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 high edge) > | Tue Nov 4 16:53:47 2008 ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level) > | Tue Nov 4 16:53:47 2008 Enabling APIC mode: Flat. Using 5 I/O APICs > | > | I think this has become possible since: > | > | commit d6c88a507ef0b6afdb013cba4e7804ba7324d99a > | Author: Thomas Gleixner > | Date: Wed Oct 15 15:27:23 2008 +0200 > | > | genirq: revert dynarray > | > | Revert the dynarray changes. They need more thought and polishing. > | > | Signed-off-by: Thomas Gleixner [...] > Hi Ben, > > I don't think that is because of Thomas' commit. If we've got > number of pins larger then we expect it means something wrong > with our NR_IRQS. Is it possible to get your .config? Well there must have been an earlier change that resulted in detecting 5 IOAPICs instead of just 1, but that presumably would work as long as the irq_desc array was dynamically allocated. This reversion breaks that. You don't really need to see the config; NR_IRQS is *always* 224 on normal x86-32 systems. Ben. -- Ben Hutchings, Senior Software Engineer, Solarflare Communications Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.