Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965273AbXBBEcv (ORCPT ); Thu, 1 Feb 2007 23:32:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965127AbXBBEcv (ORCPT ); Thu, 1 Feb 2007 23:32:51 -0500 Received: from smtp.osdl.org ([65.172.181.24]:60294 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965038AbXBBEcu (ORCPT ); Thu, 1 Feb 2007 23:32:50 -0500 Date: Thu, 1 Feb 2007 20:32:46 -0800 From: Andrew Morton To: "Lapo TIN" Cc: , Subject: Re: smp and irq conflict Message-Id: <20070201203246.ece495f0.akpm@linux-foundation.org> In-Reply-To: <45BE4003005C2845@vsmtp2.tin.it> References: <45BE4003005C2845@vsmtp2.tin.it> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2542 Lines: 54 On Thu, 1 Feb 2007 18:46:00 +0100 "Lapo TIN" wrote: > Dear all, > I have a problem with IRQs. > > My pc has a CPU PentiumD945 (dual core) and a 2.6.19smp kernel. > I have two video acquisition board (four bt8t8 each) in the only two pci > slots of my motherboard. Thus I have a total of 8 bttv modules that are > working together, and the /proc/interrupts is as follows: > # cat /proc/interrupts > CPU0 CPU1 > 0: 13575 0 IO-APIC-edge timer > 1: 2 0 IO-APIC-edge i8042 > 4: 11 0 IO-APIC-edge serial > 8: 1 0 IO-APIC-edge rtc > 9: 0 0 IO-APIC-fasteoi acpi > 12: 4 0 IO-APIC-edge i8042 > 14: 22286 0 IO-APIC-edge ide0 > 17: 7073 2097 IO-APIC-fasteoi uhci_hcd:usb5, eth0 > 18: 2525 0 IO-APIC-fasteoi bttv0, bttv7 > 19: 2829 0 IO-APIC-fasteoi bttv1, bttv4 > 20: 2526 0 IO-APIC-fasteoi bttv2, bttv5 > 21: 2226 0 IO-APIC-fasteoi bttv3, bttv6 > 22: 2 0 IO-APIC-fasteoi ehci_hcd:usb1, uhci_hcd:usb4 > 23: 86 0 IO-APIC-fasteoi uhci_hcd:usb2 > 24: 0 0 IO-APIC-fasteoi uhci_hcd:usb3 > NMI: 0 0 > LOC: 13484 13502 > ERR: 0 > MIS: 0 > You can see that IRQ18 is shared between bttv0 and bttv7, IRQ19 between > bttv1 and bttv4 and so on. > > Sometimes it crashes. It seems a matter of conflict in IRQ. > With only one video board everything is ok, but with two, they shared irq > and something goes wrong... > How can I tell to the kernel to not to share the IRQ for these boards ? > I think (I don't know if I'm right) that this could be the problem. > > I even tried with another motherboard, and doing cat /proc/interrupts the > situation was the same, except for 'eth0' that was together with bttv0 and > bttv7... so it was even worst ! it crashes after few minutes. > > I tried to read IO-APIC.txt in Documentation/i386/ folder, but I didn't > understand how to avoid the coupling of IRQ. > Thanks Should be OK. Can you provide us with any kernel output from these crashes? - 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/