From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by dpdk.space (Postfix) with ESMTP id 505A7A0679 for ; Tue, 2 Apr 2019 15:38:53 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 476742E81; Tue, 2 Apr 2019 15:38:52 +0200 (CEST) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by dpdk.org (Postfix) with ESMTP id 844602C36 for ; Tue, 2 Apr 2019 15:38:51 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Apr 2019 06:38:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,300,1549958400"; d="scan'208";a="333016893" Received: from aburakov-mobl1.ger.corp.intel.com (HELO [10.237.220.103]) ([10.237.220.103]) by fmsmga006.fm.intel.com with ESMTP; 02 Apr 2019 06:38:48 -0700 To: John Sucaet , dev@dpdk.org, Maxime Coquelin References: <20190312093826.GA914268@bricha3-MOBL.ger.corp.intel.com> <20190312102009.GA932176@bricha3-MOBL.ger.corp.intel.com> <38327cd0-7fa2-9172-5343-0cded8e51594@intel.com> <38a5d7ab-7449-fabb-46f7-6acf9d99680f@oneaccess-net.com> From: "Burakov, Anatoly" Message-ID: Date: Tue, 2 Apr 2019 14:38:47 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.6.0 MIME-Version: 1.0 In-Reply-To: <38a5d7ab-7449-fabb-46f7-6acf9d99680f@oneaccess-net.com> Content-Type: text/plain; charset="UTF-8"; format="flowed" Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] Query : Does Binding with vfio-pci is supported inside qemu-kvm guest/vm instance.? X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Message-ID: <20190402133847.f_JhfOfbk6eMx4cXXpT8P9g33Qh_KT96GsHoYk8cwK0@z> On 02-Apr-19 11:38 AM, John Sucaet wrote: > Hi Anatoly, > > As you said: There's no reason to use igb_uio, ever! That was partly tongue in cheek, but point taken :) > I would like to ask whether vfio-pci with or without vIOMMU should/could > work for virtio-pci net devices in the case of a 32-bit dpdk > application, on a 64-bit kernel (4.9) inside a guest VM > (qemu-2.10.2-1.fc27)? > > I tried both a 64-bit and a 32-bit version of the same application, but > only in the case of the 64-bit application, the port was found by eal. > The 32-bit application gave errors like: > > EAL: pci_map_resource(): cannot mmap(16, 0xf4a01000, 0x4000, 0x0): > Invalid argument (0xffffffff) > EAL: Failed to map pci BAR4 > EAL:   0000:00:02.0 mapping BAR4 failed: Invalid argument > EAL: Can't write to PCI bar (0) : offset (12) > EAL: Can't read from PCI bar (0) : offset (12) > EAL: Can't read from PCI bar (0) : offset (12) > EAL: Can't write to PCI bar (0) : offset (12) > EAL: Can't read from PCI bar (0) : offset (12) > EAL: Can't write to PCI bar (0) : offset (12) > EAL: Can't read from PCI bar (0) : offset (0) > EAL: Can't write to PCI bar (0) : offset (4) > EAL: Can't write to PCI bar (0) : offset (14) > EAL: Can't read from PCI bar (0) : offset (14) > EAL: Can't read from PCI bar (0) : offset (1a) > EAL: Can't read from PCI bar (0) : offset (1c) > EAL: Can't write to PCI bar (0) : offset (e) > EAL: Can't read from PCI bar (0) : offset (c) > virtio_init_queue(): virtqueue size is not powerof 2 > EAL: Requested device 0000:00:02.0 cannot be used > > Maybe you have an idea what went wrong here? > > By preference, I would like to continue to use the 32-bit application > which worked fine with the igb_uio driver. Unfortunately, i am not very familiar with virtio and wouldn't know whether it's supposed to work under these conditions. Perhaps Maxime would be of more help here (CC'd). > > > Thanks > > John > > > On 03/12/2019 11:57 AM, Burakov, Anatoly wrote: >> On 12-Mar-19 10:20 AM, Bruce Richardson wrote: >>> On Tue, Mar 12, 2019 at 05:54:39PM +0800, Jason Wang wrote: >>>> >>>> On 2019/3/12 下午5:42, Thanneeru Srinivasulu wrote: >>>>> Thanks Bruce.. >>>>> >>>>> On Tue, Mar 12, 2019 at 3:08 PM Bruce Richardson >>>>> wrote: >>>>>> On Tue, Mar 12, 2019 at 10:57:55AM +0530, Thanneeru Srinivasulu >>>>>> wrote: >>>>>>> Hi Everyone. >>>>>>> >>>>>>> I did attached pice  to Guest VM using vfio-pci with qemu >>>>>>> command, and then >>>>>>> tried binding the pcie bdf with vfio-pci, observing binding >>>>>>> failure with >>>>>>> vfio-pci. >>>>>>> >>>>>>> Where as when tryied with igb_uio, everything works fine. >>>>>>> >>>>>>> Does Binding with vfio-pci is supported inside VM/guest? >>>>>>> >>>>>> vfio support requires the presence of an IOMMU, and you generally >>>>>> don't >>>>>> have an IOMMU available in a VM. >>>>>> >>>>>> /Bruce >>>> >>>> >>>> Actually, Qemu support vIOMMU + VFIO in guest[1], all you need is to >>>> add a >>>> intel IOMMU and enabling caching mode. >>>> >>>> Thanks >>>> >>>> >>>> [1] >>>> >>>> https://www.lfasiallc.com/wp-content/uploads/2017/11/Device-Assignment-with-Nested-Guests-and-DPDK_Peter-Xu.pdf >>>> >>>> >>> Thanks for the info. >>> >>> /Bruce >>> >> >> One more thing: even without vIOMMU, VFIO has no-IOMMU mode which can >> be enabled (for a recent-enough kernel). This will make VFIO work even >> in cases where the guest doesn't have IOMMU emulation. See? There's no >> reason to use igb_uio, ever! :D >> > > -- Thanks, Anatoly