From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756058AbZHPVBY (ORCPT ); Sun, 16 Aug 2009 17:01:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754753AbZHPVBY (ORCPT ); Sun, 16 Aug 2009 17:01:24 -0400 Received: from bu3sch.de ([62.75.166.246]:59967 "EHLO vs166246.vserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753948AbZHPVBX (ORCPT ); Sun, 16 Aug 2009 17:01:23 -0400 From: Michael Buesch To: Thomas Gleixner Subject: Re: Threaded interrupt handlers broken? Date: Sun, 16 Aug 2009 23:01:21 +0200 User-Agent: KMail/1.9.9 Cc: linux-kernel@vger.kernel.org References: <200908161153.14081.mb@bu3sch.de> <200908161951.13988.mb@bu3sch.de> In-Reply-To: X-Move-Along: Nothing to see here. No, really... Nothing. MIME-Version: 1.0 Content-Disposition: inline Message-Id: <200908162301.21775.mb@bu3sch.de> Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sunday 16 August 2009 22:05:59 Thomas Gleixner wrote: > On Sun, 16 Aug 2009, Michael Buesch wrote: > > On Sunday 16 August 2009 16:25:13 Thomas Gleixner wrote: > > > On Sun, 16 Aug 2009, Michael Buesch wrote: > > > > On Sunday 16 August 2009 15:22:29 Thomas Gleixner wrote: > > > > > > > > > > + if (0&&unlikely(desc->status & IRQ_DISABLED)) { > > > > > > > > > > So the interrupt is marked disabled. How do you setup the handler > > > > > ? And what does the primary handler do ? Can you post your driver > > > > > code please? > > > > > > > > This patch converts the b43 driver to threaded interrupts: > > > > http://bu3sch.de/patches/wireless-testing/20090816-1535/patches/002-b43-threaded-irq-handler.patch > > > > > > On the first glance this looks not too bad. the unlocked access to the > > > irq status registers looks a bit scary, but that is not relevant for > > > the problem at hand. > > > > Yeah it does ;) > > > > > > It kind of works with this hack applied to kernel/irq/manage.c > > > > > > Hmm. Is the interrupt of the device shared ? > > > > It's registered as shared, but on my machine it is not shared with anything else. > > > > > If yes, what's the other > > > device on that interrupt line ? what puzzles me is the fact that the > > > IRQ_DISABLED flag is set. Is there anything unusual in dmesg ? > > > > Here's my current kernel log with the two patches applied: > > http://bu3sch.de/misc/dmesg > > Hmm. Nothing interesting AFAICT, but it would be really interesting to > find out why the IRQ_DISABLED flag is set. > > Can you add some debug into disable_irq() e.g. WARN_ON(irq == > BC43_IRQ_NR); so we can see what disables that interrupt. I do not see a warning, if I put this into __disable_irq(): WARN_ON(irq == 52); /proc/interrupts shows 52 as IRQ number for b43. And dmesg shows "... irq 52 on host ... mapped to virtual irq 52". So I guess the test is OK and the flag is added by some other means. Maybe by some weird powerpc architecture code? It seems a little bit weird, however, that the WARN_ON does not even trigger on module unload, which as far as I can tell should disable the IRQ line in the free_irq() call (no other shared devices on this IRQ). -- Greetings, Michael.