From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932288Ab3GBGT6 (ORCPT ); Tue, 2 Jul 2013 02:19:58 -0400 Received: from e28smtp02.in.ibm.com ([122.248.162.2]:50451 "EHLO e28smtp02.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932116Ab3GBGT5 (ORCPT ); Tue, 2 Jul 2013 02:19:57 -0400 Message-ID: <51D27044.6050604@linux.vnet.ibm.com> Date: Tue, 02 Jul 2013 11:46:36 +0530 From: "Srivatsa S. Bhat" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120828 Thunderbird/15.0 MIME-Version: 1.0 To: James Hogan CC: linux-kernel@vger.kernel.org, Thomas Gleixner Subject: Re: [PATCH 5/5] metag: cpu hotplug: route_irq: preserve irq mask References: <1372694659-30176-1-git-send-email-james.hogan@imgtec.com> <1372694659-30176-6-git-send-email-james.hogan@imgtec.com> In-Reply-To: <1372694659-30176-6-git-send-email-james.hogan@imgtec.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13070206-5816-0000-0000-000008B8C67D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/01/2013 09:34 PM, James Hogan wrote: > The route_irq() function needs to preserve the irq mask by using the > _irqsave/irqrestore variants of raw spin lock functions instead of the > _irq variants. This is because it is called from __cpu_disable() (via > migrate_irqs()), which is called with IRQs disabled, so using the _irq > variants re-enables IRQs. > > This appears to have been causing occasional hits of the > BUG_ON(!irqs_disabled()) in __irq_work_run() during CPU hotplug soak > testing: > BUG: failure at kernel/irq_work.c:122/__irq_work_run()! > > Signed-off-by: James Hogan > --- Reviewed-by: Srivatsa S. Bhat Regards, Srivatsa S. Bhat > arch/metag/kernel/irq.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/metag/kernel/irq.c b/arch/metag/kernel/irq.c > index d91b1e9..2a2c9d5 100644 > --- a/arch/metag/kernel/irq.c > +++ b/arch/metag/kernel/irq.c > @@ -279,11 +279,12 @@ static void route_irq(struct irq_data *data, unsigned int irq, unsigned int cpu) > { > struct irq_desc *desc = irq_to_desc(irq); > struct irq_chip *chip = irq_data_get_irq_chip(data); > + unsigned long flags; > > - raw_spin_lock_irq(&desc->lock); > + raw_spin_lock_irqsave(&desc->lock, flags); > if (chip->irq_set_affinity) > chip->irq_set_affinity(data, cpumask_of(cpu), false); > - raw_spin_unlock_irq(&desc->lock); > + raw_spin_unlock_irqrestore(&desc->lock, flags); > } > > /* >