From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 20 May 2001 13:12:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 20 May 2001 13:12:43 -0400 Received: from penguin.e-mind.com ([195.223.140.120]:6424 "EHLO penguin.e-mind.com") by vger.kernel.org with ESMTP id ; Sun, 20 May 2001 13:12:31 -0400 Date: Sun, 20 May 2001 19:12:06 +0200 From: Andrea Arcangeli To: Andrew Morton Cc: Ivan Kokshaysky , Richard Henderson , linux-kernel@vger.kernel.org Subject: Re: alpha iommu fixes Message-ID: <20010520191206.A30738@athlon.random> In-Reply-To: <20010519231131.A2840@jurassic.park.msu.ru>; <20010520044013.A18119@athlon.random> <3B07AF49.5A85205F@uow.edu.au> <20010520154958.E18119@athlon.random>, <20010520154958.E18119@athlon.random>; <20010520181803.I18119@athlon.random> <3B07EEFE.43DDBA5C@uow.edu.au>, <3B07EEFE.43DDBA5C@uow.edu.au>; <20010520184411.K18119@athlon.random> <3B07F6B8.4EAB0142@uow.edu.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3B07F6B8.4EAB0142@uow.edu.au>; from andrewm@uow.edu.au on Mon, May 21, 2001 at 02:54:16AM +1000 X-GnuPG-Key-URL: http://e-mind.com/~andrea/aa.gnupg.asc X-PGP-Key-URL: http://e-mind.com/~andrea/aa.asc Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 21, 2001 at 02:54:16AM +1000, Andrew Morton wrote: > No. Most of the pci_map_single() implementations just > use virt_to_bus()/virt_to_phys(). [..] then you are saying that on the platforms without an iommu the pci_map_* cannot fail, of course, furthmore even a missing pci_unmap cannot trigger an iommu address space leak on those platforms. That has nothing to do with the fact pci_map_single can fail or not, the device drivers are not architectural specific. > [..] 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. Otherwise it means it's sleeping or looping inside the pci_map functions which would break things in another manner. Andrea