From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751016AbWDMP5j (ORCPT ); Thu, 13 Apr 2006 11:57:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751032AbWDMP5j (ORCPT ); Thu, 13 Apr 2006 11:57:39 -0400 Received: from lixom.net ([66.141.50.11]:63394 "EHLO mail.lixom.net") by vger.kernel.org with ESMTP id S1751016AbWDMP5i (ORCPT ); Thu, 13 Apr 2006 11:57:38 -0400 Date: Thu, 13 Apr 2006 10:57:17 -0500 To: Muli Ben-Yehuda Cc: Olof Johansson , linuxppc-dev@ozlabs.org, paulus@samba.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [2/2] POWERPC: Lower threshold for DART enablement to 1GB, V2 Message-ID: <20060413155717.GF24769@pb15.lixom.net> References: <20060413020559.GC24769@pb15.lixom.net> <20060413022809.GD24769@pb15.lixom.net> <20060413025233.GE24769@pb15.lixom.net> <20060413064027.GH10412@granada.merseine.nu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060413064027.GH10412@granada.merseine.nu> User-Agent: Mutt/1.5.11 From: Olof Johansson Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 13, 2006 at 09:40:27AM +0300, Muli Ben-Yehuda wrote: > On Wed, Apr 12, 2006 at 09:52:33PM -0500, Olof Johansson wrote: > > > iommu=off can still be used for those who don't want to deal with the > > overhead (and don't need it for any devices). > > I've been pondering walking the PCI bus before deciding to enable an > IOMMU and checking each device's DMA mask. Is this something that you > considered and rejected, or just something no one got around to doing? It's something I thought about, but right now we enable the IOMMU quite early during boot. It'd take a bit of surgery to shuffle things, and I decided that it's not worth the work (and risk of regressions) for 2.6.17. -Olof