From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267508AbUBTEDM (ORCPT ); Thu, 19 Feb 2004 23:03:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267502AbUBTEDM (ORCPT ); Thu, 19 Feb 2004 23:03:12 -0500 Received: from adsl-66-127-195-58.dsl.snfc21.pacbell.net ([66.127.195.58]:18048 "EHLO panda.mostang.com") by vger.kernel.org with ESMTP id S267508AbUBTEDL (ORCPT ); Thu, 19 Feb 2004 23:03:11 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <16437.34558.298388.89482@panda.mostang.com> Date: Thu, 19 Feb 2004 20:03:10 -0800 To: Bill Davidsen Cc: David Mosberger-Tang , Linux Kernel Mailing List Subject: Re: [PATCH] Intel x86-64 support merge In-Reply-To: <40353382.8010505@tmr.com> References: <1qK5k-7g2-67@gated-at.bofh.it> <1qK5k-7g2-69@gated-at.bofh.it> <1qK5k-7g2-71@gated-at.bofh.it> <1qK5k-7g2-73@gated-at.bofh.it> <1qK5k-7g2-65@gated-at.bofh.it> <40353382.8010505@tmr.com> X-Mailer: VM 7.18 under Emacs 21.3.1 Reply-To: David.Mosberger@acm.org X-URL: http://www.mostang.com/~davidm/ From: davidm@mostang.com (David Mosberger-Tang) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >>>>> On Thu, 19 Feb 2004 17:06:58 -0500, Bill Davidsen said: Bill> David Mosberger-Tang wrote: >>>>>>> On Thu, 19 Feb 2004 00:40:24 +0100, Arjan van de Ven >>>>>>> said: >> Arjan> On Wed, 2004-02-18 at 23:57, H. Peter Anvin wrote: >> >> Because they were caught by surprise and just hacked the chips >> >> they had in the pipeline, presumably. Arjan> fair enough; I hope this means the next generation has this Arjan> wart fixed... >> I wouldn't hold my breath. My impression was that the Intel >> chipset folks don't want I/O MMU because (a) Windows doesn't need >> it and (b) real machines use (close-to-)64-bit-capable hardware. Bill> Doesn't need it? Does that mean the Win64 uses bounce buffers Bill> for everything? Or am I totally misreading this? Remember: I'm just the messenger here... I have no idea what Win64 does, but obviously bounce buffering is only an issue for devices that can't address all physical memory. These days, even relatively low-end machines have devices that can address "more than enough" physical memory (I'm not sure exactly what the DMA limit of, say, a Kenai32 e1000 card is, but it's a lot more than 4GB). --david