From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758939AbYDJUMX (ORCPT ); Thu, 10 Apr 2008 16:12:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757444AbYDJUMI (ORCPT ); Thu, 10 Apr 2008 16:12:08 -0400 Received: from mail29.messagelabs.com ([216.82.249.147]:14984 "HELO mail29.messagelabs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1757388AbYDJUMF (ORCPT ); Thu, 10 Apr 2008 16:12:05 -0400 X-VirusChecked: Checked X-Env-Sender: Uwe.Kleine-Koenig@digi.com X-Msg-Ref: server-14.tower-29.messagelabs.com!1207858325!10563985!1 X-StarScan-Version: 5.5.12.14.2; banners=-,-,- X-Originating-IP: [66.77.174.21] Date: Thu, 10 Apr 2008 22:11:03 +0200 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= To: "Hans J. Koch" , Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/4] UIO: hold a reference to the device's owner while the device is open Message-ID: <20080410201103.GB16292@digi.com> References: <1207831023-8583-1-git-send-email-Uwe.Kleine-Koenig@digi.com> <1207831023-8583-2-git-send-email-Uwe.Kleine-Koenig@digi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1207831023-8583-2-git-send-email-Uwe.Kleine-Koenig@digi.com> User-Agent: Mutt/1.5.13 (2006-08-11) X-OriginalArrivalTime: 10 Apr 2008 20:11:03.0511 (UTC) FILETIME=[00999E70:01C89B47] X-TM-AS-Product-Ver: SMEX-8.0.0.1181-5.000.1023-15842.001 X-TM-AS-Result: No--8.293000-8.000000-2 X-TM-AS-User-Approved-Sender: No X-TM-AS-User-Blocked-Sender: No Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Uwe Kleine-König wrote: > Otherwise the device might just disappear while /dev/uioX is being used > which results in an Oops. To help your understanding, without this patch I can trigger the Oops by starting an app that does opening and mmapping /dev/uio0 while(1); and then in another shell do rmmod uio_pdrv Best regards Uwe -- Uwe Kleine-König, Software Engineer Digi International GmbH Branch Breisach, Küferstrasse 8, 79206 Breisach, Germany Tax: 315/5781/0242 / VAT: DE153662976 / Reg. Amtsgericht Dortmund HRB 13962