From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261605AbUEJU6w (ORCPT ); Mon, 10 May 2004 16:58:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261611AbUEJU6w (ORCPT ); Mon, 10 May 2004 16:58:52 -0400 Received: from coyote.holtmann.net ([217.160.111.169]:57802 "EHLO mail.holtmann.net") by vger.kernel.org with ESMTP id S261605AbUEJU6u (ORCPT ); Mon, 10 May 2004 16:58:50 -0400 Subject: Re: [PATCH] hci-usb bugfix From: Marcel Holtmann To: Oliver Neukum Cc: Alan Stern , Sebastian Schmidt , Linux Kernel Mailing List In-Reply-To: <200405102238.11876.oliver@neukum.org> References: <200405102115.26504.oliver@neukum.org> <1084217971.9639.55.camel@pegasus> <200405102238.11876.oliver@neukum.org> Content-Type: text/plain Message-Id: <1084222715.9639.105.camel@pegasus> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Mon, 10 May 2004 22:58:35 +0200 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi Oliver, > > which results in the same as if we set NULL for the private pointer when > > we claim the second interface. If this really happens then we have more > > problems in the driver itself, because this case won't be handled in > > either way. However I don't think that this will happen, because for > > You can trigger it in software through usbfs. I've never done this before. Can you show me how? > > Bluetooth devices interface 0 and 1 can be seen as a unit. The only > > reason that this was split over two interfaces, was that you don't have > > to stop the bulk transfers when you change the altsetting on the second > > interface. > > Yes, but you should really stop using the second interface _before_ > returning returning from disconnect() for _that_ interface. You will > operate correctly if the primary interface is disconnected first, > but you cannot depend on that. If the secondary interface is > disconnected first, you have a window where you illegally use an > interface you no longer own. You are absolutely right and this needs to be fixed, but this problem is a different one than that my patch fixes. However this problem is now on my todo list. Thanks for making me aware of. Regards Marcel