From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938946AbXHIHyi (ORCPT ); Thu, 9 Aug 2007 03:54:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S938007AbXHIHyX (ORCPT ); Thu, 9 Aug 2007 03:54:23 -0400 Received: from ns1.suse.de ([195.135.220.2]:52150 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936872AbXHIHyR (ORCPT ); Thu, 9 Aug 2007 03:54:17 -0400 Date: Thu, 9 Aug 2007 00:19:32 -0700 From: Greg KH To: Jesper Juhl Cc: "Valdis.Kletnieks@vt.edu" , linux-kernel@vger.kernel.org, "Hans J. Koch" Subject: Re: [PATCH 2/3] UIO: Documentation Message-ID: <20070809071932.GA22318@suse.de> References: <20070718232332.GA4620@kroah.com> <11848012053678-git-send-email-gregkh@suse.de> <11848012122374-git-send-email-gregkh@suse.de> <9a8748490708081436g23c8f01cga585d6612b380f16@mail.gmail.com> <14166.1186611154@turing-police.cc.vt.edu> <9a8748490708081603k65746311sad595947fd5ab971@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9a8748490708081603k65746311sad595947fd5ab971@mail.gmail.com> User-Agent: Mutt/1.5.15 (2007-04-06) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 09, 2007 at 01:03:39AM +0200, Jesper Juhl wrote: > > > I think the only way to avoid it is to not provide something like UIO. Problem is, things like UIO provide a real solution for a wide range of different types of devices. Like the one provided in the kernel right now, and a bunch of others that I am currently discussing with different manufacturers (think high-speed DSPs that just want to give userspace direct access to the card and have the kernel get the hell out of the way so data can be read and processed as fast as possible.) And also realize that some types of systems have been doing this very same kind of kernel/userspace interface for many years, namely X :) As for the legalities of using closed source userspace code with the UIO interface, consult a lawyer if you have questions, and be sure to bring up Alan's comments about derivative works :) thanks, greg k-h