From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754301AbdDON4G (ORCPT ); Sat, 15 Apr 2017 09:56:06 -0400 Received: from terminus.zytor.com ([65.50.211.136]:45425 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753901AbdDON4D (ORCPT ); Sat, 15 Apr 2017 09:56:03 -0400 Date: Sat, 15 Apr 2017 06:54:51 -0700 From: tip-bot for Hans de Goede Message-ID: Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, hdegoede@redhat.com, tglx@linutronix.de, marc.zyngier@arm.com, hpa@zytor.com Reply-To: hpa@zytor.com, marc.zyngier@arm.com, tglx@linutronix.de, hdegoede@redhat.com, mingo@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20170415100831.17073-1-hdegoede@redhat.com> References: <20170415100831.17073-1-hdegoede@redhat.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:irq/core] genirq: Use irqd_get_trigger_type to compare the trigger type for shared IRQs Git-Commit-ID: 382bd4de61827dbaaf5fb4fb7b1f4be4a86505e7 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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 382bd4de61827dbaaf5fb4fb7b1f4be4a86505e7 Gitweb: http://git.kernel.org/tip/382bd4de61827dbaaf5fb4fb7b1f4be4a86505e7 Author: Hans de Goede AuthorDate: Sat, 15 Apr 2017 12:08:31 +0200 Committer: Thomas Gleixner CommitDate: Sat, 15 Apr 2017 15:42:43 +0200 genirq: Use irqd_get_trigger_type to compare the trigger type for shared IRQs When requesting a shared irq with IRQF_TRIGGER_NONE then the irqaction flags get filled with the trigger type from the irq_data: if (!(new->flags & IRQF_TRIGGER_MASK)) new->flags |= irqd_get_trigger_type(&desc->irq_data); On the first setup_irq() the trigger type in irq_data is NONE when the above code executes, then the irq is started up for the first time and then the actual trigger type gets established, but that's too late to fix up new->flags. When then a second user of the irq requests the irq with IRQF_TRIGGER_NONE its irqaction's triggertype gets set to the actual trigger type and the following check fails: if (!((old->flags ^ new->flags) & IRQF_TRIGGER_MASK)) Resulting in the request_irq failing with -EBUSY even though both users requested the irq with IRQF_SHARED | IRQF_TRIGGER_NONE Fix this by comparing the new irqaction's trigger type to the trigger type stored in the irq_data which correctly reflects the actual trigger type being used for the irq. Suggested-by: Thomas Gleixner Signed-off-by: Hans de Goede Acked-by: Marc Zyngier Link: http://lkml.kernel.org/r/20170415100831.17073-1-hdegoede@redhat.com Signed-off-by: Thomas Gleixner --- kernel/irq/manage.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 155e3c3..ae1c90f 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1212,8 +1212,10 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) * set the trigger type must match. Also all must * agree on ONESHOT. */ + unsigned int oldtype = irqd_get_trigger_type(&desc->irq_data); + if (!((old->flags & new->flags) & IRQF_SHARED) || - ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK) || + (oldtype != (new->flags & IRQF_TRIGGER_MASK)) || ((old->flags ^ new->flags) & IRQF_ONESHOT)) goto mismatch;