From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932112AbWGXLXf (ORCPT ); Mon, 24 Jul 2006 07:23:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932117AbWGXLXf (ORCPT ); Mon, 24 Jul 2006 07:23:35 -0400 Received: from mtagate2.uk.ibm.com ([195.212.29.135]:42720 "EHLO mtagate2.uk.ibm.com") by vger.kernel.org with ESMTP id S932112AbWGXLXf (ORCPT ); Mon, 24 Jul 2006 07:23:35 -0400 Date: Mon, 24 Jul 2006 13:21:12 +0200 From: Heiko Carstens To: Andrew Morton Cc: Arjan van de Ven , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org Subject: [patch] pi-futex: missing pi_waiters plist initialization Message-ID: <20060724112112.GA16537@osiris.boeblingen.de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: mutt-ng/devel-r804 (Linux) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Heiko Carstens Initialize init task's pi_waiters plist. Otherwise cpu hotplug of cpu 0 might crash, since rt_mutex_getprio() accesses an uninitialized list head. call chain which led to crash: take_cpu_down sched_idle_next __setscheduler rt_mutex_getprio Using PLIST_HEAD_INIT in the INIT_TASK macro doesn't work unfortunately, since the pi_waiters member is only conditionally present. Cc: Arjan van de Ven Cc: Thomas Gleixner Cc: Ingo Molnar Signed-off-by: Heiko Carstens --- kernel/sched.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/sched.c b/kernel/sched.c index b44b9a4..db1014d 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -6761,6 +6761,11 @@ #endif } set_load_weight(&init_task); + +#ifdef CONFIG_RT_MUTEXES + plist_head_init(&init_task.pi_waiters, &init_task.pi_lock); +#endif + /* * The boot idle thread does lazy MMU switching as well: */