From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264830AbTLQXi2 (ORCPT ); Wed, 17 Dec 2003 18:38:28 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264855AbTLQXi2 (ORCPT ); Wed, 17 Dec 2003 18:38:28 -0500 Received: from mx1.redhat.com ([66.187.233.31]:32734 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S264830AbTLQXi1 (ORCPT ); Wed, 17 Dec 2003 18:38:27 -0500 Date: Wed, 17 Dec 2003 18:38:25 -0500 From: Alan Cox To: Andi Kleen Cc: Alan Cox , linux-kernel@vger.kernel.org Subject: Re: PCI Express support for 2.4 kernel Message-ID: <20031217233825.GK10132@devserv.devel.redhat.com> References: <131Ac-5Qy-3@gated-at.bofh.it> <137cD-8eg-9@gated-at.bofh.it> <13kD2-1kF-11@gated-at.bofh.it> <13qIi-31G-1@gated-at.bofh.it> <13DvZ-2RY-9@gated-at.bofh.it> <13DFw-3a8-9@gated-at.bofh.it> <13DPq-3s4-7@gated-at.bofh.it> <13Fem-6iy-7@gated-at.bofh.it> <13SY1-35z-19@gated-at.bofh.it> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 18, 2003 at 12:22:02AM +0100, Andi Kleen wrote: > Alan Cox writes: > > > > And X11 will want to access it via /proc interfaces. And someone will eventually > > go and design a different way to access PCI-EX for their hardware 8) > > It would be nice if it did. Just currently it uses racy port accesses > from user space :-( Depends what patches you applied and how you built it 8) However XFree meets hotplug is so unfunny its not good to consider before dinner, nor XFree meets irqs or XFree meets SAK and high security models. Linus had a nice comment that the basic DRI/fb modules should be dealing with the PCI layer and perhaps exposing the DMA engine for newer cards (to trusted parties). For older cards there are all sorts of reasons you don't want to do this on the performance side but even then a driver which refused to free up the PCI map space until X noticed the file handle was returning errors and selected EOF would make a lot of the stuff sort out. Maybe in part the GGI folks were right all those years ago. We had two extreme views and the middle may be closer Alan