Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758836AbXEQV5I (ORCPT ); Thu, 17 May 2007 17:57:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756575AbXEQV45 (ORCPT ); Thu, 17 May 2007 17:56:57 -0400 Received: from ns2.suse.de ([195.135.220.15]:51734 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756450AbXEQV44 (ORCPT ); Thu, 17 May 2007 17:56:56 -0400 Date: Thu, 17 May 2007 23:56:54 +0200 From: Bernhard Walle To: Vivek Goyal Cc: Morton Andrew Morton , linux kernel mailing list Subject: Re: 2.6.21-rc7-mm2 "irqpoll" seems to be broken Message-ID: <20070517215654.GA31149@suse.de> Mail-Followup-To: Vivek Goyal , Morton Andrew Morton , linux kernel mailing list References: <20070426093620.GB2626@in.ibm.com> <20070426082405.67a0fdd2.akpm@linux-foundation.org> <20070430084833.GA16173@in.ibm.com> <20070502221932.GA488@suse.de> <20070508171841.GA29733@in.ibm.com> <20070514140513.GD29616@suse.de> <20070517130527.GF28280@in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070517130527.GF28280@in.ibm.com> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1609 Lines: 34 * Vivek Goyal [2007-05-17 15:05]: > On Mon, May 14, 2007 at 04:05:15PM +0200, Bernhard Walle wrote: > > * Vivek Goyal [2007-05-08 19:18]: > > > On Thu, May 03, 2007 at 12:19:32AM +0200, Bernhard Walle wrote: > > > > * Vivek Goyal [2007-04-30 10:48]: > > > > > > > > > > handle_edge_irq() already makes sure that desc->action is not null, still > > > > > note_interrupt() is receiving desc->action as null, that's strange. On my > > > > > system this is happening for irq 4 and /proc/interrupt shows that it is > > > > > coming from "serial". > > > > > > > > Unfortunately, I couldn't reproduce this here. Vivek, do you have time > > > > to take a look at this at your site? For the meanwhile, should I > > > > create a patch that checks for desc->action in note_interrupt(), too? > > > > > > I can reproduce this problem only on one machine. I think there is some > > > race condition and your code somehow just exposes it. > > > > thanks for finding that out. Could you try/review out the patch below? > > As the lock is only aquired when irqfixup == 2 it shouldn't impact > > performance of a 'normal' system. > > It does fix up my problem. I have modified your patch a bit. I think > new version is little more clear. What do you think? Aggreed. Thanks for spotting that problem out! Bernhard - 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/