From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756936Ab1K3Jmz (ORCPT ); Wed, 30 Nov 2011 04:42:55 -0500 Received: from www.linutronix.de ([62.245.132.108]:36980 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752816Ab1K3Jmx (ORCPT ); Wed, 30 Nov 2011 04:42:53 -0500 Date: Wed, 30 Nov 2011 10:42:46 +0100 (CET) From: Thomas Gleixner To: Linus Torvalds cc: Ingo Molnar , Dave Airlie , linux-kernel@vger.kernel.org, drivers_pci@kernel-bugs.osdl.org, =?ISO-8859-15?Q?Rog=E9rio_Brito?= Subject: Re: [Bug 41132] [BISECTED][REGRESSION] Regression with the IRQ subsystem introduced in 2.6.39 (and present in the 3.x version) In-Reply-To: Message-ID: References: <201108160554.p7G5soeq002083@demeter2.kernel.org> User-Agent: Alpine 2.02 (LFD 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 27 Nov 2011, Linus Torvalds wrote: > Thomas, Ingo? > > I haven't seen any response to this one, and while clearly commit > fa27271bc8d2 ("genirq: Fixup poll handling") was *supposed* to be a > no-op, it isn't. > > The commit message says "Shorter version with the same > functionality.", but since it causes a regression, it clearly is not > with the same functionality at all. And I assume that Thomas doesn't > have a machine that actually ever triggers the spurious irq issue to > begin with, so it probably was never tested. > > In short, it really sounds like this should just be reverted, since > the code clearly doesn't do what the commit message claims it does. > > Comments? Yes, Edward tracked it down already. One part of the fix is already in your tree commit 52553ddffad. The second half is in my queue. See below. Thanks, tglx ------> >>From edward.donovan@numble.net Sun Nov 20 02:57:17 2011 Date: Sat, 19 Nov 2011 20:54:23 -0500 From: Edward Donovan To: tglx@linutronix.de Cc: linux-kernel@vger.kernel.org, maciej.rutecki@gmail.com Subject: [PATCH] genirq: fix second 2.6.39 regression in irqfixup, irqpoll commit fa2727("genirq: Fixup poll handling") introduced a regression that broke irqfixup/irqpoll for some hardware configurations. That patch removed a test that checked for 'action->handler' returning IRQ_HANDLED, before acting on the IRQ. Putting this test back restores the functionality lost since 2.6.39. In the current set of tests after 'action' is set, it must precede '!action->next' to take effect. With this and the previous patch to spurious.c, c75d720fca8a, all IRQ regressions that I have encountered are fixed. Signed-off-by: Edward Donovan --- kernel/irq/spurious.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c index b5f4742..dc813a9 100644 --- a/kernel/irq/spurious.c +++ b/kernel/irq/spurious.c @@ -84,7 +84,9 @@ static int try_one_irq(int irq, struct irq_desc *desc, bool force) */ action = desc->action; if (!action || !(action->flags & IRQF_SHARED) || - (action->flags & __IRQF_TIMER) || !action->next) + (action->flags & __IRQF_TIMER) || + (action->handler(irq, action->dev_id) == IRQ_HANDLED) || + !action->next) goto out; /* Already running on another processor */ -- 1.7.5.4