From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752883Ab1HDQhz (ORCPT ); Thu, 4 Aug 2011 12:37:55 -0400 Received: from casper.infradead.org ([85.118.1.10]:43105 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751758Ab1HDQht convert rfc822-to-8bit (ORCPT ); Thu, 4 Aug 2011 12:37:49 -0400 Subject: Re: [ANNOUNCE] 3.0-rt6 : BUG at kernel/trmutex.c:724! From: Peter Zijlstra To: Tim Sander Cc: Thomas Gleixner , LKML , linux-rt-users , "Paul E. McKenney" In-Reply-To: <201108041834.20575.tim.sander@hbm.com> References: <201108041834.20575.tim.sander@hbm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Thu, 04 Aug 2011 18:37:09 +0200 Message-ID: <1312475829.16729.45.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2011-08-04 at 18:34 +0200, Tim Sander wrote: > I was really happy to find 6 preempt rt releases for the 3.0 kernel after holliday :-). > > So i went for a testdrive and found an error: The error occurs in a non released non > mainline kernel and is available from me upon request. It has been working on > (2.6.39,3.0) but is not working on 3.0-rt6. It fails in an interrupt which calls: > > wake_up_interruptible(&hbm_device.wait); > > The waitque has been initialized with: > init_waitqueue_head(&hbm_device.wait); > before interrupts where enabled. So i don't think its a race. looks like it tries to use waitqueues from hardirq context, that's a no-no for -rt. That interrupt should be a threaded interrupt.