From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Fjellstrom Subject: Re: Status of pci passthrough work? Date: Sun, 28 Sep 2008 19:09:26 -0600 Message-ID: <200809281909.26934.tfjellstrom@shaw.ca> References: <200809262020.16885.tfjellstrom@shaw.ca> <200809270157.47022.tfjellstrom@shaw.ca> <200809281240.32545.amit.shah@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit To: kvm@vger.kernel.org Return-path: Received: from idcmail-mo1so.shaw.ca ([24.71.223.10]:64822 "EHLO idcmail-mo1so.shaw.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753042AbYI2BJa (ORCPT ); Sun, 28 Sep 2008 21:09:30 -0400 In-Reply-To: <200809281240.32545.amit.shah@redhat.com> Content-Disposition: inline Sender: kvm-owner@vger.kernel.org List-ID: On Sunday 28 September 2008, Amit Shah wrote: > * On Saturday 27 Sep 2008 13:27:46 Thomas Fjellstrom wrote: > > On Saturday 27 September 2008, Han, Weidong wrote: > > > Thomas Fjellstrom wrote: > > > > On Saturday 27 September 2008, Han, Weidong wrote: > > > >> Hi Thomas, > > > >> > > > >> the patches of passthrough/VT-d on kvm.git are already checked in. > > > >> With Amit's userspace patches, you can assign device to guest. You > > > >> can have a try. > > > > > > > > Does that mean I need VT-d support in hardware? All I have to test > > > > with right now is an AMD Phenom X4 with a 780g+sb700 system. Don't > > > > think it has an iommu, and I'd find it odd if the intel VT-d code > > > > "just worked" on amd's hardware. > > > > > > 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? > > 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? > > > >> Thomas Fjellstrom wrote: > > > >>> I'm very interested in being able to pass a few devices through to > > > >>> kvm guests. I'm wondering what exactly is working now, and how I > > > >>> can start testing it? > > > >>> > > > >>> the latest kvm release doesn't seem to include any support for it > > > >>> in userspace, so I can't test it with that... > > The userspace patch is undergoing pre-merge revisions. > > I'll send out an email once I get my git trees synced up to my working > revisions. > > In the meantime, you can use the patches from the list. Its rather hard to find the patches from before I joined the list, most archives don't keep attachments. > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Thanks for the heads up, and all the work on this stuff :) -- Thomas Fjellstrom tfjellstrom@shaw.ca