Return-Path: <linux-kernel-owner+willy=40w.ods.org-S268700AbUJUJ0j@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S268700AbUJUJ0j (ORCPT <rfc822;willy@w.ods.org>);
	Thu, 21 Oct 2004 05:26:39 -0400
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S269056AbUJUJ0Z
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Thu, 21 Oct 2004 05:26:25 -0400
Received: from 213-239-205-147.clients.your-server.de ([213.239.205.147]:7331
	"EHLO debian.tglx.de") by vger.kernel.org with ESMTP
	id S268700AbUJUJYc (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Thu, 21 Oct 2004 05:24:32 -0400
Subject: Re: [patch] Real-Time Preemption, -RT-2.6.9-rc4-mm1-U8
From: Thomas Gleixner <tglx@linutronix.de>
Reply-To: tglx@linutronix.de
To: Rui Nuno Capela <rncbc@rncbc.org>
Cc: Ingo Molnar <mingo@elte.hu>, LKML <linux-kernel@vger.kernel.org>,
       Lee Revell <rlrevell@joe-job.com>, mark_h_johnson@raytheon.com,
       "K.R. Foley" <kr@cybsft.com>, Bill Huey <bhuey@lnxw.com>,
       Adam Heath <doogie@debian.org>, Florian Schmidt <mista.tapas@gmx.net>,
       Michal Schmidt <xschmi00@stud.feec.vutbr.cz>,
       Fernando Pablo Lopez-Lezcano <nando@ccrma.stanford.edu>
In-Reply-To: <30690.195.245.190.93.1098349976.squirrel@195.245.190.93>
References: <20041012195424.GA3961@elte.hu> <20041013061518.GA1083@elte.hu>
	 <20041014002433.GA19399@elte.hu> <20041014143131.GA20258@elte.hu>
	 <20041014234202.GA26207@elte.hu> <20041015102633.GA20132@elte.hu>
	 <20041016153344.GA16766@elte.hu> <20041018145008.GA25707@elte.hu>
	 <20041019124605.GA28896@elte.hu> <20041019180059.GA23113@elte.hu>
	 <20041020094508.GA29080@elte.hu>
	 <30690.195.245.190.93.1098349976.squirrel@195.245.190.93>
Content-Type: text/plain
Organization: linutronix
Message-Id: <1098350190.26758.24.camel@thomas>
Mime-Version: 1.0
X-Mailer: Ximian Evolution 1.4.6 
Date: Thu, 21 Oct 2004 11:16:30 +0200
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 623
Lines: 18

On Thu, 2004-10-21 at 11:12, Rui Nuno Capela wrote:
>  [<e018e139>] queuecommand+0x70/0x7c [usb_storage] (24)

As I already pointed out, this is a problem due to up(sema) in
queuecommand. That's one of the semaphore abuse points, which needs to
be fixed. 

The problem is that semaphores are hold by Process A and released by
Process B, which makes Ingo's checks trigger

tglx


-
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/