From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williamson Subject: Re: [Announcement] 2015-Q3 release of XenGT - a Mediated Graphics Passthrough Solution from Intel Date: Thu, 19 Nov 2015 08:52:46 -0700 Message-ID: <1447948366.4697.119.camel@redhat.com> References: <53D215D3.50608@intel.com> <547FCAAD.2060406@intel.com> <54AF967B.3060503@intel.com> <5527CEC4.9080700@intel.com> <559B3E38.1080707@intel.com> <562F4311.9@intel.com> <1447870341.4697.92.camel@redhat.com> <564D78D0.80904@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by gabe.freedesktop.org (Postfix) with ESMTPS id 99AE86E9BA for ; Thu, 19 Nov 2015 07:52:48 -0800 (PST) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Stefano Stabellini Cc: "igvt-g@ml01.01.org" , "Reddy, Raghuveer" , "White, Michael L" , "Cowperthwaite, David J" , "intel-gfx@lists.freedesktop.org" , "Li, Susie" , "Dong, Eddie" , "linux-kernel@vger.kernel.org" , qemu-devel , "Zhou, Chao" , Paolo Bonzini , "Zhu, Libo" , "xen-devel@lists.xen.org" , "Wang, Hongbo" List-Id: intel-gfx@lists.freedesktop.org T24gVGh1LCAyMDE1LTExLTE5IGF0IDE1OjMyICswMDAwLCBTdGVmYW5vIFN0YWJlbGxpbmkgd3Jv dGU6Cj4gT24gVGh1LCAxOSBOb3YgMjAxNSwgSmlrZSBTb25nIHdyb3RlOgo+ID4gSGkgQWxleCwg dGhhbmtzIGZvciB0aGUgZGlzY3Vzc2lvbi4KPiA+IAo+ID4gSW4gYWRkaXRpb24gdG8gS2V2aW4n cyByZXBsaWVzLCBJIGhhdmUgYSBoaWdoLWxldmVsIHF1ZXN0aW9uOiBjYW4gVkZJTwo+ID4gYmUg dXNlZCBieSBRRU1VIGZvciBib3RoIEtWTSBhbmQgWGVuPwo+IAo+IE5vLiBWRklPIGNhbm5vdCBi ZSB1c2VkIHdpdGggWGVuIHRvZGF5LiBXaGVuIHJ1bm5pbmcgb24gWGVuLCB0aGUgSU9NTVUKPiBp cyBvd25lZCBieSBYZW4uCgpSaWdodCwgYnV0IGluIHRoaXMgY2FzZSB3ZSdyZSB0YWxraW5nIGFi b3V0IGRldmljZSBNTVVzLCB3aGljaCBhcmUgb3duZWQKYnkgdGhlIGRldmljZSBkcml2ZXIgd2hp Y2ggSSB0aGluayBpcyBydW5uaW5nIGluIGRvbTAsIHJpZ2h0PyAgVGhpcwpwcm9wb3NhbCBkb2Vz bid0IHJlcXVpcmUgc3VwcG9ydCBvZiB0aGUgc3lzdGVtIElPTU1VLCB0aGUgZG9tMCBkcml2ZXIK bWFwcyBJT1ZBIHRyYW5zbGF0aW9ucyBqdXN0IGFzIGl0IHdvdWxkIGZvciBpdHNlbGYuICBXZSdy ZSBsYXJnZWx5CnByb3Bvc2luZyB1c2Ugb2YgdGhlIFZGSU8gQVBJIHRvIHByb3ZpZGUgYSBjb21t b24gaW50ZXJmYWNlIHRvIGV4cG9zZSBhClBDSShlKSBkZXZpY2UgdG8gUUVNVSwgYnV0IHdoYXQg aGFwcGVucyBpbiB0aGUgdkdQVSB2ZW5kb3IgZGV2aWNlIGFuZApJT01NVSBiYWNrZW5kcyBpcyBz cGVjaWZpYyB0byB0aGUgZGV2aWNlIGFuZCBwZXJoYXBzIGV2ZW4gc3BlY2lmaWMgdG8KdGhlIGh5 cGVydmlzb3IuICBUaGFua3MsCgpBbGV4CgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fXwpJbnRlbC1nZnggbWFpbGluZyBsaXN0CkludGVsLWdmeEBsaXN0cy5m cmVlZGVza3RvcC5vcmcKaHR0cDovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3Rp bmZvL2ludGVsLWdmeAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934378AbbKSPwt (ORCPT ); Thu, 19 Nov 2015 10:52:49 -0500 Received: from mx1.redhat.com ([209.132.183.28]:53943 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934179AbbKSPws (ORCPT ); Thu, 19 Nov 2015 10:52:48 -0500 Message-ID: <1447948366.4697.119.camel@redhat.com> Subject: Re: [Intel-gfx] [Announcement] 2015-Q3 release of XenGT - a Mediated Graphics Passthrough Solution from Intel From: Alex Williamson To: Stefano Stabellini Cc: Jike Song , "Tian, Kevin" , "xen-devel@lists.xen.org" , "igvt-g@ml01.01.org" , "intel-gfx@lists.freedesktop.org" , "linux-kernel@vger.kernel.org" , "White, Michael L" , "Dong, Eddie" , "Li, Susie" , "Cowperthwaite, David J" , "Reddy, Raghuveer" , "Zhu, Libo" , "Zhou, Chao" , "Wang, Hongbo" , "Lv, Zhiyuan" , qemu-devel , Paolo Bonzini , Gerd Hoffmann Date: Thu, 19 Nov 2015 08:52:46 -0700 In-Reply-To: References: <53D215D3.50608@intel.com> <547FCAAD.2060406@intel.com> <54AF967B.3060503@intel.com> <5527CEC4.9080700@intel.com> <559B3E38.1080707@intel.com> <562F4311.9@intel.com> <1447870341.4697.92.camel@redhat.com> <564D78D0.80904@intel.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2015-11-19 at 15:32 +0000, Stefano Stabellini wrote: > On Thu, 19 Nov 2015, Jike Song wrote: > > Hi Alex, thanks for the discussion. > > > > In addition to Kevin's replies, I have a high-level question: can VFIO > > be used by QEMU for both KVM and Xen? > > No. VFIO cannot be used with Xen today. When running on Xen, the IOMMU > is owned by Xen. Right, but in this case we're talking about device MMUs, which are owned by the device driver which I think is running in dom0, right? This proposal doesn't require support of the system IOMMU, the dom0 driver maps IOVA translations just as it would for itself. We're largely proposing use of the VFIO API to provide a common interface to expose a PCI(e) device to QEMU, but what happens in the vGPU vendor device and IOMMU backends is specific to the device and perhaps even specific to the hypervisor. Thanks, Alex From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42035) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZzRW1-0001Jm-Gd for qemu-devel@nongnu.org; Thu, 19 Nov 2015 10:52:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZzRVx-0001PY-Dq for qemu-devel@nongnu.org; Thu, 19 Nov 2015 10:52:53 -0500 Received: from mx1.redhat.com ([209.132.183.28]:59327) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZzRVx-0001PU-8K for qemu-devel@nongnu.org; Thu, 19 Nov 2015 10:52:49 -0500 Message-ID: <1447948366.4697.119.camel@redhat.com> From: Alex Williamson Date: Thu, 19 Nov 2015 08:52:46 -0700 In-Reply-To: References: <53D215D3.50608@intel.com> <547FCAAD.2060406@intel.com> <54AF967B.3060503@intel.com> <5527CEC4.9080700@intel.com> <559B3E38.1080707@intel.com> <562F4311.9@intel.com> <1447870341.4697.92.camel@redhat.com> <564D78D0.80904@intel.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [Intel-gfx] [Announcement] 2015-Q3 release of XenGT - a Mediated Graphics Passthrough Solution from Intel List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefano Stabellini Cc: "igvt-g@ml01.01.org" , Jike Song , "Reddy, Raghuveer" , qemu-devel , "White, Michael L" , "Cowperthwaite, David J" , "intel-gfx@lists.freedesktop.org" , "Li, Susie" , "Dong, Eddie" , "Tian, Kevin" , "linux-kernel@vger.kernel.org" , Gerd Hoffmann , "Zhou, Chao" , Paolo Bonzini , "Zhu, Libo" , "xen-devel@lists.xen.org" , "Wang, Hongbo" , "Lv, Zhiyuan" On Thu, 2015-11-19 at 15:32 +0000, Stefano Stabellini wrote: > On Thu, 19 Nov 2015, Jike Song wrote: > > Hi Alex, thanks for the discussion. > > > > In addition to Kevin's replies, I have a high-level question: can VFIO > > be used by QEMU for both KVM and Xen? > > No. VFIO cannot be used with Xen today. When running on Xen, the IOMMU > is owned by Xen. Right, but in this case we're talking about device MMUs, which are owned by the device driver which I think is running in dom0, right? This proposal doesn't require support of the system IOMMU, the dom0 driver maps IOVA translations just as it would for itself. We're largely proposing use of the VFIO API to provide a common interface to expose a PCI(e) device to QEMU, but what happens in the vGPU vendor device and IOMMU backends is specific to the device and perhaps even specific to the hypervisor. Thanks, Alex