Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262243AbVCJWlQ (ORCPT ); Thu, 10 Mar 2005 17:41:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262370AbVCJWkV (ORCPT ); Thu, 10 Mar 2005 17:40:21 -0500 Received: from sccrmhc13.comcast.net ([204.127.202.64]:18651 "EHLO sccrmhc13.comcast.net") by vger.kernel.org with ESMTP id S263309AbVCJWc1 (ORCPT ); Thu, 10 Mar 2005 17:32:27 -0500 Message-ID: <4230CB07.3020904@comcast.net> Date: Thu, 10 Mar 2005 17:32:39 -0500 From: John Richard Moser User-Agent: Mozilla Thunderbird 1.0 (X11/20050111) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Peter Chubb CC: linux-kernel@vger.kernel.org Subject: Re: binary drivers and development References: <423075B7.5080004@comcast.net> <423082BF.6060007@comcast.net> <16944.49977.715895.8761@wombat.chubb.wattle.id.au> In-Reply-To: <16944.49977.715895.8761@wombat.chubb.wattle.id.au> X-Enigmail-Version: 0.90.0.0 X-Enigmail-Supports: pgp-inline, pgp-mime 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: 2037 Lines: 57 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Peter Chubb wrote: >>>>>>"John" == John Richard Moser writes: > > > > John> I've done more thought, here's a small list of advantages on > John> using binary drivers, specifically considering UDI. You can > John> consider a different implementation for binary drivers as well, > John> with most of the same advantages. > > Almost all these advantages are also present for user-mode drivers... > and getting drivers out of the kernel, where possible, is a much > better approach IMHO than trying to maintain a leaky in-kernel > interface. The problem with in-kernel interfaces, even if set in > concrete, is that any binary driver can go outside the interface --- > there's no encapsulation --- and so break when the kernel changes. > CPL=3 scares me; context switches are expensive. can they have direct hardware access? I'm sure a security model to isolate user mode drivers could be in place. . . . . . huh. Xen seems to run Linux at CPL=3 and give direct hardware access, so I guess user mode drivers are possible *shrug*. Linux isn't a microkernel though. > Peter C > > > - -- All content of all messages exchanged herein are left in the Public Domain, unless otherwise explicitly stated. Creative brains are a valuable, limited resource. They shouldn't be wasted on re-inventing the wheel when there are so many fascinating new problems waiting out there. -- Eric Steven Raymond -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.5 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD4DBQFCMMsGhDd4aOud5P8RAjoOAJ9Owgnd5QOp9MfrQ8PzOLAt/A7k+wCYmxLc wvXLkQX84Z2PF2J4oEIbVA== =wi8f -----END PGP SIGNATURE----- - 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/