From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 22 May 2001 17:05:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 22 May 2001 17:05:27 -0400 Received: from cisco7500-mainGW.gts.cz ([194.213.32.131]:6148 "EHLO bug.ucw.cz") by vger.kernel.org with ESMTP id ; Tue, 22 May 2001 17:05:09 -0400 Message-ID: <20010522151143.A9541@bug.ucw.cz> Date: Tue, 22 May 2001 15:11:43 +0200 From: Pavel Machek To: "David S. Miller" , Andrea Arcangeli Cc: Andrew Morton , Ivan Kokshaysky , Richard Henderson , linux-kernel@vger.kernel.org Subject: Re: alpha iommu fixes In-Reply-To: <20010519231131.A2840@jurassic.park.msu.ru> <20010520044013.A18119@athlon.random> <3B07AF49.5A85205F@uow.edu.au> <20010520154958.E18119@athlon.random> <20010520181803.I18119@athlon.random> <3B07EEFE.43DDBA5C@uow.edu.au> <20010520184411.K18119@athlon.random> <3B07F6B8.4EAB0142@uow.edu.au> <20010520191206.A30738@athlon.random> <15112.27206.4123.40450@pizda.ninka.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.93i In-Reply-To: <15112.27206.4123.40450@pizda.ninka.net>; from David S. Miller on Sun, May 20, 2001 at 06:07:17PM -0700 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! > > > [..] Even sparc64's fancy > > > iommu-based pci_map_single() always succeeds. > > > > Whatever sparc64 does to hide the driver bugs you can break it if you > > pci_map 4G+1 bytes of phyical memory. > > Which is an utterly stupid thing to do. > > Please construct a plausable situation where this would occur legally > and not be a driver bug, given the maximum number of PCI busses and > slots found on sparc64 and the maximum _concurrent_ usage of PCI dma > space for any given driver (which isn't doing something stupid). What stops you from plugging PCI-to-PCI bridges in order to create some large number of slots, like 128? Pavel -- I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care." Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org