From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755618AbbGPP3H (ORCPT ); Thu, 16 Jul 2015 11:29:07 -0400 Received: from down.free-electrons.com ([37.187.137.238]:52953 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751000AbbGPP3E (ORCPT ); Thu, 16 Jul 2015 11:29:04 -0400 Date: Thu, 16 Jul 2015 17:29:02 +0200 From: Alexandre Belloni To: Thomas Gleixner Cc: David Dueck , linux-kernel@vger.kernel.org, bigeasy@linutronix.de, nicolas.ferre@atmel.com, ludovic.desroches@atmel.com, boris.brezillon@free-electrons.com, maxime.ripard@free-electrons.com, wsteinwender@pcs.com, antoine.tenart@free-electrons.com, mail@jann.io, c.emde@osadl.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 2/2] at91: use request_irq/free_irq instead of setup_irq/remove_irq Message-ID: <20150716152902.GN20482@piout.net> References: <1435937609-18623-1-git-send-email-davidcdueck@googlemail.com> <1435937609-18623-2-git-send-email-davidcdueck@googlemail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 05/07/2015 at 23:48:26 +0200, Thomas Gleixner wrote : > On Fri, 3 Jul 2015, David Dueck wrote: > > > This fixes a warning when using RT-Preempt. > > That's not a proper explanation for the patch and by all means it > cannot fix anything because free_irq() is just a different wrapper > around __free_irq() than remove_irq(). So how on earth fixes that the > problem at hand? > Hum, that is quite simple, the following patch http://git.kernel.org/cgit/linux/kernel/git/rt/linux-rt-devel.git/commit/?id=227cd21851456fb08e87f5a35e0e51280a9fd439 bitrotted and should be rewritten completely or at least dropped. For drivers/clocksource/timer-atmel-st.c, the patch is broken since at least 3.18 as NR_IRQS_LEGACY + AT91_ID_SYS is 17 and the actual irq allocated by irq_of_parse_and_map is 16. Since 4.1, AT91_ID_SYS doesn't exist anymore and this is not compiling at all. For drivers/clocksource/timer-atmel-pit.c, struct irqaction at91sam926x_pit_irq is never initialized but then it is used in setup_irq()/remove_irq(). This basically ends up registering a null handler for IRQ 0. I'm preparing a replacement patch. I'd even say that this is probably something we would want to mainline. Meanwhile, can you drop the mentioned patch? -- Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com