From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266898AbUH1GUf (ORCPT ); Sat, 28 Aug 2004 02:20:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267197AbUH1GUN (ORCPT ); Sat, 28 Aug 2004 02:20:13 -0400 Received: from jade.spiritone.com ([216.99.193.136]:49852 "EHLO jade.spiritone.com") by vger.kernel.org with ESMTP id S266898AbUH1GR7 (ORCPT ); Sat, 28 Aug 2004 02:17:59 -0400 Date: Fri, 27 Aug 2004 23:17:47 -0700 From: "Martin J. Bligh" To: john stultz , lkml cc: William Lee Irwin III , James , keith maanthey , Chris McDermott Subject: Re: [RFC][PATCH] fix target_cpus() for summit subarch Message-ID: <79750000.1093673866@[10.10.2.4]> In-Reply-To: <1093652688.14662.16.camel@cog.beaverton.ibm.com> References: <1093652688.14662.16.camel@cog.beaverton.ibm.com> X-Mailer: Mulberry/2.2.1 (Linux/x86) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --john stultz wrote (on Friday, August 27, 2004 17:24:48 -0700): > I've been hunting down a bug affecting IBM x440/x445 systems where the > floppy driver would get spurious interrupts and would not initialize > properly. > > After digging James Cleverdon pointed out that target_cpus() is routing > the interrupts to the clustered apic broadcast mask. This was causing > multiple interrupts to show up, breaking the floppy init code. > > This one-liner fix simply routes interrupts to the first cpu to resolve > this issue. I'd say that means your hardware is horribly broken ... but I guess this might be a suitable workaround given we're going to reprogram them all later. So ... do all your interrupts end up on the first cpu now, or does irqbalance take care of it? M.