From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755361AbYISTwh (ORCPT ); Fri, 19 Sep 2008 15:52:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754025AbYISTw3 (ORCPT ); Fri, 19 Sep 2008 15:52:29 -0400 Received: from outbound-va3.frontbridge.com ([216.32.180.16]:45599 "EHLO VA3EHSOBE003.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753895AbYISTw2 (ORCPT ); Fri, 19 Sep 2008 15:52:28 -0400 X-BigFish: VPS-34(z1039oz146fK1418M1432R98dR1805M179dR936fQ873fnzz10d3izz2f39iz32i6bh43j61h) X-Spam-TCS-SCL: 0:0 X-FB-SS: 5, X-WSS-ID: 0K7GKIX-04-2GC-01 Date: Fri, 19 Sep 2008 21:52:16 +0200 From: Joerg Roedel To: FUJITA Tomonori CC: mingo@elte.hu, linux-kernel@vger.kernel.org Subject: Re: [PATCH] remove fullflush and nofullflush in IOMMU generic option Message-ID: <20080919195216.GB10692@amd.com> References: <20080919173004.GA9837@amd.com> <20080920024046W.fujita.tomonori@lab.ntt.co.jp> <20080919180118.GV24392@amd.com> <20080920034750X.fujita.tomonori@lab.ntt.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20080920034750X.fujita.tomonori@lab.ntt.co.jp> User-Agent: mutt-ng/devel-r804 (Linux) X-OriginalArrivalTime: 19 Sep 2008 19:52:16.0134 (UTC) FILETIME=[378D0A60:01C91A91] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Sep 20, 2008 at 03:48:11AM +0900, FUJITA Tomonori wrote: > On Fri, 19 Sep 2008 20:01:18 +0200 > Joerg Roedel wrote: > > > On Sat, Sep 20, 2008 at 02:40:35AM +0900, FUJITA Tomonori wrote: > > > On Fri, 19 Sep 2008 19:30:04 +0200 > > > Joerg Roedel wrote: > > > > > > > On Sat, Sep 20, 2008 at 02:09:21AM +0900, FUJITA Tomonori wrote: > > > > > > > > > > Please keep it for AMD option for now. Please send a patch to make it > > > > > generic to other IOMMU people and give them a chance to discuss on > > > > > it. > > > > > > > > > > > > > Btw, you already agreed with a generic iommu= parameter for lazy IO/TLB > > > > flushing" > > > > > > > > > > > > > True. We should merge common parameters across IOMMUs into the > > > > > iommu= parameter some time in the future, I think. It would also be the > > > > > place for the IOMMU size parameter. > > > > > > > > Hmm, now is better than the future? I think that now you can add > > > > something like 'disable_batching_flush' as a common parameter and > > > > change AMD IOMMU to use it. > > > > > > > > in http://lkml.org/lkml/2008/9/17/376 > > > > > > > > And since we already have a iommu=fullflush parameter it makes sense of > > > > make it generic. > > > > > > I'm not against fullflush but we need to discuss it with other people > > > before making the change. > > > > Weird. Just 2 hours ago you wrote: > > > > |http://lkml.org/lkml/2008/9/19/106 > > | > > |For me, adding these boot parameters doesn't make sense. > > See: > > http://lkml.org/lkml/2008/9/19/221 Removing nofullflush and moving fullflush to the generic code are two different questions. You talk about the first and I talk about the second here. We should make sure we talk about the same things when we flame each other ;) > > > Anyway, I wrote to the Intel and Calgary developers and asked them for > > their opinion. If they have real objections I am the last person NACKing > > your original patch in this thread again. > > I think that I already expressed a real objection for nofullflush > twice though I'm not the maintainer of any IOMMUs. And I agree with that. But AMD IOMMU updates are not the right place to remove it. > > The reason why I queued this patch in AMD IOMMU updates was that I > > didn't wanted to implement an option specificly for AMD IOMMU when there > > will be a generic one soon. This is double work I prefered to do it > > You were not sure that they will be generic before discussion. Since Intel has lazy flushing too it is generic enough. Its only the question if the Intel VT-d maintainer want to use it. Joerg -- | AMD Saxony Limited Liability Company & Co. KG Operating | Wilschdorfer Landstr. 101, 01109 Dresden, Germany System | Register Court Dresden: HRA 4896 Research | General Partner authorized to represent: Center | AMD Saxony LLC (Wilmington, Delaware, US) | General Manager of AMD Saxony LLC: Dr. Hans-R. Deppe, Thomas McCoy