From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756553Ab3BURqv (ORCPT ); Thu, 21 Feb 2013 12:46:51 -0500 Received: from terminus.zytor.com ([198.137.202.10]:42915 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754397Ab3BURqu (ORCPT ); Thu, 21 Feb 2013 12:46:50 -0500 Date: Thu, 21 Feb 2013 09:45:03 -0800 From: tip-bot for Thomas Gleixner Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, torvalds@linuxfoundation.org, peterz@infradead.org, paulmck@linux.vnet.ibm.com, fweisbec@gmail.com, tglx@linutronix.de Reply-To: paulmck@linux.vnet.ibm.com, mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, fweisbec@gmail.com, torvalds@linuxfoundation.org, peterz@infradead.org, tglx@linutronix.de In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:irq/urgent] irq: Ensure irq_exit() code runs with interrupts disabled Git-Commit-ID: 630e7580f681475d92d87e78373e4136096e12f2 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (terminus.zytor.com [127.0.0.1]); Thu, 21 Feb 2013 09:45:10 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 630e7580f681475d92d87e78373e4136096e12f2 Gitweb: http://git.kernel.org/tip/630e7580f681475d92d87e78373e4136096e12f2 Author: Thomas Gleixner AuthorDate: Wed, 20 Feb 2013 22:00:48 +0100 Committer: Thomas Gleixner CommitDate: Thu, 21 Feb 2013 18:32:44 +0100 irq: Ensure irq_exit() code runs with interrupts disabled We had already a few problems with code called from irq_exit() when interrupted from a nesting interrupt. This can happen on architectures which do not define __ARCH_IRQ_EXIT_IRQS_DISABLED. __ARCH_IRQ_EXIT_IRQS_DISABLED should go away and we want to make it mandatory to call irq_exit() with interrupts disabled. As a temporary protection disable interrupts for those architectures which do not define __ARCH_IRQ_EXIT_IRQS_DISABLED and add a WARN_ONCE when an architecture which defines __ARCH_IRQ_EXIT_IRQS_DISABLED calls irq_exit() with interrupts enabled. Signed-off-by: Thomas Gleixner Cc: Frederic Weisbecker Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Paul E. McKenney Cc: Linus Torvalds Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1302202155320.22263@ionos --- kernel/softirq.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/kernel/softirq.c b/kernel/softirq.c index f5cc25f..d1f7943 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -341,6 +341,14 @@ static inline void invoke_softirq(void) */ void irq_exit(void) { +#ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED + unsigned long flags; + + local_irq_save(flags); +#else + WARN_ON_ONCE(!irqs_disabled(); +#endif + account_irq_exit_time(current); trace_hardirq_exit(); sub_preempt_count(IRQ_EXIT_OFFSET); @@ -354,6 +362,9 @@ void irq_exit(void) #endif rcu_irq_exit(); sched_preempt_enable_no_resched(); +#ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED + local_irq_restore(flags); +#endif } /*