From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965185AbZLHA0L (ORCPT ); Mon, 7 Dec 2009 19:26:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935725AbZLHA0L (ORCPT ); Mon, 7 Dec 2009 19:26:11 -0500 Received: from sh.osrg.net ([192.16.179.4]:41752 "EHLO sh.osrg.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935718AbZLHA0K (ORCPT ); Mon, 7 Dec 2009 19:26:10 -0500 Date: Tue, 8 Dec 2009 09:24:47 +0900 To: yinghai@kernel.org Cc: mingo@elte.hu, linux-kernel@vger.kernel.org Subject: Re: [PATCH -tip] x86: fix iommu=soft boot option From: FUJITA Tomonori In-Reply-To: <20091202170715K.fujita.tomonori@lab.ntt.co.jp> References: <20091202162510Q.fujita.tomonori@lab.ntt.co.jp> <4B161D70.3030301@kernel.org> <20091202170715K.fujita.tomonori@lab.ntt.co.jp> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-Id: <20091208092438Z.fujita.tomonori@lab.ntt.co.jp> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-3.0 (sh.osrg.net [192.16.179.4]); Tue, 08 Dec 2009 09:24:48 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2 Dec 2009 17:07:24 +0900 FUJITA Tomonori wrote: > On Tue, 01 Dec 2009 23:55:28 -0800 > Yinghai Lu wrote: > > > >>>> amd 64 systems that > > >>>> 1. do not have AGP > > >>>> 2. do not have IOMMU > > >>>> 3. mem > 4g > > >>>> 4. BIOS do not allocate correct gart in NB. > > >>>> will leave them to use SWIOTLB forcely. > > >>> As I asked earlier, can you tell me what dma ops such system is > > >>> supposed to use? > > >> gart_dma_ops > > > > > > How does gart_dma_ops work on systems without IOMMU? > > > > ? > > If a system doesn't have IOMMU, what does gart_dma_ops do? Ping? I don't understand the above but the patch is fine about fixing two things: - swiotlb wrongly steals the preallocate memory for broken gart. - a system without agp should disable gart on shutdown.