From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757581Ab3LBUY0 (ORCPT ); Mon, 2 Dec 2013 15:24:26 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:39018 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752576Ab3LBTRE (ORCPT ); Mon, 2 Dec 2013 14:17:04 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Pfaff , Ivo Sieben , Sebastian Andrzej Siewior , Thomas Gleixner Subject: [PATCH 3.12 026/212] genirq: Set the irq thread policy without checking CAP_SYS_NICE Date: Mon, 2 Dec 2013 11:13:37 -0800 Message-Id: <20131202191251.547725120@linuxfoundation.org> X-Mailer: git-send-email 1.8.4.3.gca3854a In-Reply-To: <20131202191248.517975703@linuxfoundation.org> References: <20131202191248.517975703@linuxfoundation.org> User-Agent: quilt/0.60-8.1.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Pfaff commit bbfe65c219c638e19f1da5adab1005b2d68ca810 upstream. In commit ee23871389 ("genirq: Set irq thread to RT priority on creation") we moved the assigment of the thread's priority from the thread's function into __setup_irq(). That function may run in user context for instance if the user opens an UART node and then driver calls requests in the ->open() callback. That user may not have CAP_SYS_NICE and so the irq thread won't run with the SCHED_OTHER policy. This patch uses sched_setscheduler_nocheck() so we omit the CAP_SYS_NICE check which is otherwise required for the SCHED_OTHER policy. [bigeasy: Rewrite the changelog] Signed-off-by: Thomas Pfaff Cc: Ivo Sieben Link: http://lkml.kernel.org/r/1381489240-29626-1-git-send-email-bigeasy@linutronix.de Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- kernel/irq/manage.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -956,7 +956,7 @@ __setup_irq(unsigned int irq, struct irq goto out_mput; } - sched_setscheduler(t, SCHED_FIFO, ¶m); + sched_setscheduler_nocheck(t, SCHED_FIFO, ¶m); /* * We keep the reference to the task struct even if