From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 25 Jan 2002 13:18:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 25 Jan 2002 13:17:51 -0500 Received: from mailhost.nmt.edu ([129.138.4.52]:29969 "EHLO mailhost.nmt.edu") by vger.kernel.org with ESMTP id ; Fri, 25 Jan 2002 13:17:41 -0500 Date: Fri, 25 Jan 2002 11:17:31 -0700 From: Val Henson To: "Albert D. Cahalan" Cc: linux-kernel@vger.kernel.org Subject: Re: Athlon/AGP issue update Message-ID: <20020125111731.B26874@boardwalk> In-Reply-To: <20020123171419.29358@mailhost.mipsys.com> <200201232314.g0NNEXe457847@saturn.cs.uml.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <200201232314.g0NNEXe457847@saturn.cs.uml.edu>; from acahalan@cs.uml.edu on Wed, Jan 23, 2002 at 06:14:33PM -0500 Favorite-Color: Polka dot Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 23, 2002 at 06:14:33PM -0500, Albert D. Cahalan wrote: > > It's a waste to use BAT mappings for the kernel anyway, because > we try to keep the huge computations and graphics in userspace. > With page tables under BAT mappings, privileged user code could > be allowed to steal BAT registers for locked memory or IO memory. The rationale behind BAT mapping the kernel is that the kernel does not use any TLB entries, leaving them all for user processes. (As long as we have < 512MB RAM.) -VAL