From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it1-f174.google.com (mail-it1-f174.google.com [209.85.166.174]) by dpdk.org (Postfix) with ESMTP id A8E9C7D05 for ; Mon, 4 Feb 2019 11:22:41 +0100 (CET) Received: by mail-it1-f174.google.com with SMTP id p197so19852417itp.0 for ; Mon, 04 Feb 2019 02:22:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netronome-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=kqr9kNB9ofW8ik8BrxS/YGFTWaUXdscwKfUJu5OaGG8=; b=BzZNJTvHyUTttTmZyjm4s8IjVIq7+MmFrWVew7nlbjBZ6jjQPJ9vNWXl/cL8Z/qAoX FhQcw8+QZmowkQF8Du7UmmdY7IsBavKgUEYThUdTqySA1xYK7NkwnmxFKani/Y0oEBEg kDzcYoGHPKNzjQHcuvqgYEB7USRogRcSY5rRs05ZfONECbAnbP945JkSo6TWuEeUaacY EbGgKWhAONMczUlizi9r5TcpFfv6C2/KGZI5AT4GAcc4hz/3p8w0xch2CupfQjCgViO3 Y2EFKuIVB90g3dN0myZnGf86IiZ+WZuon4zhG1UuuaMvxbgJBclYdR9O8o/0qFvQkxr7 95Pw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=kqr9kNB9ofW8ik8BrxS/YGFTWaUXdscwKfUJu5OaGG8=; b=eMLraRFaKuH0SLabHCKiVvMQHUIRi3aJPNbM1rtpakYCbvw22sbiYMZo4XMdnfByod roXjBIk7I0f+ckOpwqsZovndbvSu/wN9Jw0MfqUMlLMBh24yOW7mVNw317K2EyvSjn3u BHAKJzZ5gMHZkxmpNGajTnuujSnwSn0q3eE6TI5UzK/2NkKsJ/E96xXDhJ1ZFKYsXaLO mcFlmj0O8AH2o+aI5QHoJRqSWZdC8tT7aVZHlAfpTL0yiVY1dJewCx6RCbxGBkUGJYU2 sEmO9oRMZ/VuYSculJvRuhqZbpXp07PtVcWeWz+XY5oqzmCQagrX/eHrQxBkvWCSBkAh tpCw== X-Gm-Message-State: AHQUAubn7F+KDmB/AthSpcj7k0dfELa4YZWTKz+RbtbJ+ewI2zoLyGxR CE9qDSvS8pSJG75fhzy2mWs1sxBT/ByPkhuTx2xAcw== X-Google-Smtp-Source: AHgI3IYzJ0D1F3kHiboTG7ZJW4Gu3iZ3K7acxsJ4culIDgGTMr3T3zikMw6LXDfcaAzCU0ToYXj7C279qR6QjosgeVE= X-Received: by 2002:a6b:c9d4:: with SMTP id z203mr5801829iof.218.1549275760962; Mon, 04 Feb 2019 02:22:40 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Alejandro Lucero Date: Mon, 4 Feb 2019 10:22:30 +0000 Message-ID: To: Rami Rosen Cc: dev Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: Re: [dpdk-dev] A Question about the necessity of DPDK VF for Ethernet PMDs 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: , X-List-Received-Date: Mon, 04 Feb 2019 10:22:41 -0000 Hi Rami, Your concern is related to this thread: http://mails.dpdk.org/archives/dev/2019-January/123466.html I'm working on solving the problem when PF needs to be bound to VFIO. My proposal is to use mediated devices. Although it is not strictly necessary to rely on current kernel WiP about VFIO med-devices IOMMU aware https://lwn.net/Articles/763793/ using that patch makes the implementation easier. Indeed, this solution implies changes to current kernel netdev drivers, and the previous commented kernel patch will likely be accepted upstream before our push. DPDK changes for supporting mdev bus will happen soon (I hope). Intel guys are working on this for the I/O scale case Intel is interested in, with Netronome's case, and the one you point out, being a specific case which can be implemented with those DPDK and kernel changes. On Mon, Feb 4, 2019 at 7:43 AM Rami Rosen wrote: > Hello all, > > > > Now that DPDK 19.02 was released three days ago (on time!!), hopefully > there will be time > > for people to answer the following question: > > > > According to the "DPDK Getting Started Guide", > > > > "If UEFI secure boot is enabled, the Linux kernel may disallow the use of > UIO on the system. > > Therefore, devices for use by DPDK should be bound to the vfio-pci kernel > module > > rather than igb_uio or uio_pci_generic. For more details see Binding and > > Unbinding Network Ports to/from the Kernel Modules." > > See: > > > http://doc.dpdk.org/guides/linux_gsg/sys_reqs.html#bios-setting-prerequisite-on-x86 > > > > Now, when you bind a PCI device with vfio-pci, then the "max_vfs" entry is > *not* created under > > /sys/bus/pci/devices// (as opposed to the case when you bind with > igb_uio). > > This means that you cannot create DPDK VFS in this case (as you cannot > write num_vfs to the > > non existing max_vfs entry). You can however create Kernel VFs (by echoing > into the sriov_num_vfs > > sysfs entry). > > > > So I assume there are deployments of DPDK (with secure boot) when the PMDs > are being binded not by > > igb_uio but by vfio_pci. > > > > So the question is: > > As explained above, t probably there are setups when you cannot generated > PMD VFs. > > Most PMD Ethernet Vendors *do* provide VF PMDs in the DPDK official repo; > > but what are the benefits of providing DPDK VFs PMD? is it mandatory in > some use cases ? > > Is there any advantage for using a DPDK PF/DPDK VF > > combination over using Kernel VF? > > > > Regards, > > Rami Rosen >