From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753999AbaC3XdS (ORCPT ); Sun, 30 Mar 2014 19:33:18 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36521 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753136AbaC3XZE (ORCPT ); Sun, 30 Mar 2014 19:25:04 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Jan Beulich" , "Rafael J. Wysocki" , "Konrad Rzeszutek Wilk" Date: Mon, 31 Mar 2014 00:23:35 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 200/200] intel_idle: Check cpu_idle_get_driver() for NULL before dereferencing it. In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.56-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Konrad Rzeszutek Wilk commit 3735d524da64b70b41c764359da36f88aded3610 upstream. If the machine is booted without any cpu_idle driver set (b/c disable_cpuidle() has been called) we should follow other users of cpu_idle API and check the return value for NULL before using it. Reported-and-tested-by: Mark van Dijk Suggested-by: Jan Beulich Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Rafael J. Wysocki Signed-off-by: Ben Hutchings --- drivers/idle/intel_idle.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -584,8 +584,9 @@ static int __init intel_idle_init(void) intel_idle_cpuidle_driver_init(); retval = cpuidle_register_driver(&intel_idle_driver); if (retval) { + struct cpuidle_driver *drv = cpuidle_get_driver(); printk(KERN_DEBUG PREFIX "intel_idle yielding to %s", - cpuidle_get_driver()->name); + drv ? drv->name : "none"); return retval; }