From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932130Ab2ARIA4 (ORCPT ); Wed, 18 Jan 2012 03:00:56 -0500 Received: from mail.de.keymile.com ([195.8.104.1]:52055 "HELO mail.de.keymile.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S932089Ab2ARIAy (ORCPT ); Wed, 18 Jan 2012 03:00:54 -0500 From: Gerlando Falauto To: linux-kernel@vger.kernel.org Cc: Gerlando Falauto , Thomas Gleixner , Ingo Molnar , Holger Brunck Subject: [PATCH 1/1] genirq: drop synchronize_irq() unless CONFIG_SMP Date: Wed, 18 Jan 2012 08:59:57 +0100 Message-Id: <1326873597-19188-2-git-send-email-gerlando.falauto@keymile.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1326873597-19188-1-git-send-email-gerlando.falauto@keymile.com> References: <1326873597-19188-1-git-send-email-gerlando.falauto@keymile.com> X-ESAFE-STATUS: [srvhellgate.de.keymile.net] Mail clean Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since synchronize_irq() only makes sense under SMP, restore the behavior prior to: :commit 3aa551c9b4c40018f0e261a178e3d25478dc04a9 :Author: Thomas Gleixner :Date: Mon Mar 23 18:28:15 2009 +0100 : : genirq: add threaded interrupt handler support so that it is declared and defined only when CONFIG_SMP=y. Note that kernel/irq/manage.c only gets compiled when CONFIG_GENERIC_HARDIRQS=y -- if this is not the case, you should implement your own. This fixes startup deadlocks in SMP-unaware drivers which call disable_irq() within its own handler, and used to work (by chance), up until 2.6.29. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Holger Brunck Signed-off-by: Gerlando Falauto --- include/linux/hardirq.h | 2 +- kernel/irq/manage.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h index ba36217..82b2e75 100644 --- a/include/linux/hardirq.h +++ b/include/linux/hardirq.h @@ -123,7 +123,7 @@ # define IRQ_EXIT_OFFSET HARDIRQ_OFFSET #endif -#if defined(CONFIG_SMP) || defined(CONFIG_GENERIC_HARDIRQS) +#if defined(CONFIG_SMP) extern void synchronize_irq(unsigned int irq); #else # define synchronize_irq(irq) barrier() diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 0a7840a..410da46 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -28,6 +28,7 @@ static int __init setup_forced_irqthreads(char *arg) early_param("threadirqs", setup_forced_irqthreads); #endif +#if defined(CONFIG_SMP) /** * synchronize_irq - wait for pending IRQ handlers (on other CPUs) * @irq: interrupt number to wait for @@ -72,7 +73,6 @@ void synchronize_irq(unsigned int irq) } EXPORT_SYMBOL(synchronize_irq); -#ifdef CONFIG_SMP cpumask_var_t irq_default_affinity; /** -- 1.7.1