From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752402Ab2G0QUt (ORCPT ); Fri, 27 Jul 2012 12:20:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:29290 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751929Ab2G0QUs (ORCPT ); Fri, 27 Jul 2012 12:20:48 -0400 Date: Fri, 27 Jul 2012 12:20:38 -0400 From: Dave Jones To: Linux Kernel , Thomas Gleixner Subject: Re: lockdep trace from posix timers Message-ID: <20120727162038.GD12244@redhat.com> Mail-Followup-To: Dave Jones , Linux Kernel , Thomas Gleixner References: <20120724203613.GA9637@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120724203613.GA9637@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 24, 2012 at 04:36:13PM -0400, Dave Jones wrote: > Linus tree as of 5fecc9d8f59e765c2a48379dd7c6f5cf88c7d75a > > Dave > > ====================================================== > [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ] > 3.5.0+ #122 Not tainted > ------------------------------------------------------ > trinity-child2/5327 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: > blocked: (tasklist_lock){.+.+..}, instance: ffffffff81c05098, at: [] posix_cpu_timer_del+0x2b/0xe0 > > and this task is already holding: > blocked: (&(&new_timer->it_lock)->rlock){-.-...}, instance: ffff880143bce170, at: [] __lock_timer+0x89/0x1f0 > which would create a new lock dependency: > (&(&new_timer->it_lock)->rlock){-.-...} -> (tasklist_lock){.+.+..} > > but this new dependency connects a HARDIRQ-irq-safe lock: > (&(&new_timer->it_lock)->rlock){-.-...} > ... which became HARDIRQ-irq-safe at: Shall I start bisecting this ? I can trigger it very easily, but if you can give me a set of commits to narrow down, it'll speed up the bisection. Dave