Return-Path: <linux-kernel-owner+willy=40w.ods.org-S1030205AbVLSBDN@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1030205AbVLSBDN (ORCPT <rfc822;willy@w.ods.org>);
	Sun, 18 Dec 2005 20:03:13 -0500
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030206AbVLSBDN
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Sun, 18 Dec 2005 20:03:13 -0500
Received: from mtai02.charter.net ([209.225.8.182]:31645 "EHLO
	mtai02.charter.net") by vger.kernel.org with ESMTP id S1030205AbVLSBDM
	(ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Sun, 18 Dec 2005 20:03:12 -0500
X-BrightmailFiltered: true
X-Brightmail-Tracker: AAAAAQAAA+k=
Message-ID: <43A60630.4070304@cybsft.com>
Date: Sun, 18 Dec 2005 19:00:32 -0600
From: "K.R. Foley" <kr@cybsft.com>
Organization: Cybersoft Solutions, Inc.
User-Agent: Thunderbird 1.5 (X11/20051025)
MIME-Version: 1.0
To: Steven Rostedt <rostedt@goodmis.org>
CC: Ingo Molnar <mingo@elte.hu>, linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: 2.6.15-rc5-rt2 won't boot on dual 933
References: <43A5DAE4.8090908@cybsft.com> <1134953473.13138.217.camel@localhost.localdomain>
In-Reply-To: <1134953473.13138.217.camel@localhost.localdomain>
X-Enigmail-Version: 0.93.0.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 1466
Lines: 55

Steven Rostedt wrote:
> On Sun, 2005-12-18 at 15:55 -0600, K.R. Foley wrote:
>> dump_stack+0x1e/0x20 (20)
>>  [<c011c9df>] preempt_enable_no_resched+0x5f/0x70 (20)
>>  [<c0100ff2>] cpu_idle+0xb2/0x100 (40)
>>  [<c0111446>] start_secondary+0x296/0x340<6> 
> 
> Ingo,
> 
> What's the reason for this printing out in cpu_idle?
> 
> #ifdef CONFIG_DEBUG_PREEMPT
> void notrace preempt_enable_no_resched(void)
> {
> 	static int once = 1;
> 
> 	barrier();
> 	dec_preempt_count();
> 
> 	if (once && !preempt_count()) {
> 		once = 0;
> 		printk(KERN_ERR "BUG: %s:%d task might have lost a preemption check!
> \n",
> 			current->comm, current->pid);
> 		dump_stack();
> 	}
> }
> 
> EXPORT_SYMBOL(preempt_enable_no_resched);
> #endif
> 
> I can understand the above when using preempt_enable_no_resched, when
> you know that you still have preemption on, but sometimes (as in
> cpu_idle) it is used just before calling schedule.  So this check is
> pretty much meaningless.
> 
> ---
> 
> KR, 
> 
> Does your kernel boot without CONFIG_DEBUG_PREEMPT?
> 
> -- Steve

No. Already tried and got a different dump. Not sure if it was just a
dump or a dump initiated by an oops. In an hour or so I will go down and
capture that.

-- 
   kr
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/