From mboxrd@z Thu Jan 1 00:00:00 1970 From: Amit Shah Subject: Re: Status of pci passthrough work? Date: Fri, 3 Oct 2008 12:00:26 +0530 Message-ID: <200810031200.26214.amit.shah@redhat.com> References: <200809262020.16885.tfjellstrom@shaw.ca> <200809281240.32545.amit.shah@redhat.com> <200809281909.26934.tfjellstrom@shaw.ca> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org To: Thomas Fjellstrom Return-path: Received: from mx2.redhat.com ([66.187.237.31]:55948 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753125AbYJCGbp (ORCPT ); Fri, 3 Oct 2008 02:31:45 -0400 In-Reply-To: <200809281909.26934.tfjellstrom@shaw.ca> Content-Disposition: inline Sender: kvm-owner@vger.kernel.org List-ID: Please keep me in the CC to get faster replies. * On Monday 29 Sep 2008 06:39:26 Thomas Fjellstrom wrote: > > > > Yes, currently you need VT-d support in hardware to assign device. > > > > > > So I take it the PV-DMA (or pv-dma doesn't do what I think it does...) > > > or the other 1:1 device pass through work isn't working right now? > > > > pvdma does work, but the most recent patches aren't yet published (I > > should do that). It will work for simple devices. > > > > 1:1 will also work. > > Once the trees are updated? pvdma, yes. I don't have the 1:1 patches in my tree as of now. Andrea maintains those patches. > > > It's something I'd really like to use, but I don't have access to a > > > platform with a hardware iommu. Though I might be able to pick up a > > > replacement board for my new server with the SB750 southbridge which > > > supposedly has AMD's new iommu hardware in it, but I haven't seen any > > > evidence that kvm or linux supports it. > > > > Linux 2.6.27 onwards supports AMD IOMMU. kvm (and device assignment) > > support for AMD IOMMU doesn't exist yet, but work is planned to start > > soon. > > What does the kernel supporting it help a person wanting to use it to pass > through devices to guests if kvm doesn't support it? Also, what would the > kernel use it for in that case? That's right; that was just to give you an idea of how things are progressing. > Its rather hard to find the patches from before I joined the list, most > archives don't keep attachments. Sure; look for an update next week. > Thanks for the heads up, and all the work on this stuff :) You're welcome and it's always good to hear from users.