From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ob0-f173.google.com (mail-ob0-f173.google.com [209.85.214.173]) by dpdk.org (Postfix) with ESMTP id DAB41370 for ; Tue, 15 Dec 2015 12:20:47 +0100 (CET) Received: by mail-ob0-f173.google.com with SMTP id sd4so3998344obb.0 for ; Tue, 15 Dec 2015 03:20:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netronome-com.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=747TfoVM6tVy7Yl3YgPWJkZnW2/exLAz7WKg5NIBOaM=; b=w9zLLEsFaLbpFjbQoaGzzAwN6fO6lOkcDtEHpPwUVFvgQAlxm4gylqzgmm1hFgyqBZ 77YI+qd4hCncf2Yl1gTVOjXVJuxxMgT+zi9avMeca3WhYRKJUv7kze7EFvbFTKPs32a6 MLPo3o9glPTjeFyebiDuFQ+KNCUG9vSU8ZBdSjKEynrQcq6Q2qonLGSlzrIWY40twhgL s5KHLHoXXBZR3wSGr62bHuNfEnum3kCQozDssI53E80G2gz1iamf1OXoBkWW4C6fB1py fU/ht7GHsME4jamRSXEQbf8R0qHqp3YXd3SADBUTC+xpGKj/sOnnOIGWSuA4Dmm8Uwt+ IOdw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=747TfoVM6tVy7Yl3YgPWJkZnW2/exLAz7WKg5NIBOaM=; b=HyaC5MjApfXk13rBDbVC/CI5rSE0eh5FLyoz0VB7jmTaImfWwFOT737M0q/YxIeSl8 3jr5s5fztsrBt8abT4r+OGxwxWQ8iKQ5Z2+8NE79GwWMyolUpupmWAHqr5+Q2GkO3Igy LlHIgM2C91Ey4V9cliXb9J8OZe9S7Vtux+VP2I/Rpq6yB4xUghUXkKojpxtjrYAU3yja vqLZs6vxkjx5+h2h+7jht5tlWCEYOGtFu0eUfU3Ifa5DmruUezfRF1GEK18kEq1pwYlS Zhl7LQREK8rYYyg771zA1wQypefPpHufnzlCWcxDJb4/jKl5pdWYot50LJ3BdHdsbfuv I4gw== X-Gm-Message-State: ALoCoQkcQ4o7bX/gekMbINQr42asD6s1HU8jZcLu5gqy/n2WNQImuhV+zwOBWiMf7cywSNuGGRVoAUpL6mYwW1CQQGqfojm0e4slGStOLBU0NfrWxvd9Gt4= MIME-Version: 1.0 X-Received: by 10.60.95.67 with SMTP id di3mr29061921oeb.5.1450178447184; Tue, 15 Dec 2015 03:20:47 -0800 (PST) Received: by 10.76.150.99 with HTTP; Tue, 15 Dec 2015 03:20:47 -0800 (PST) In-Reply-To: <20151212002051.68708a38@jvn> References: <60420822.AbcfvjLZCk@xps13> <20151212002051.68708a38@jvn> Date: Tue, 15 Dec 2015 11:20:47 +0000 Message-ID: From: Alejandro Lucero To: Jan Viktorin Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Cc: dev , Alex Williamson Subject: Re: [dpdk-dev] VFIO no-iommu X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Dec 2015 11:20:48 -0000 Hi, I know a bit about VFIO implementation, have been debugging IOMMU (intel) problems, know how QEMU/KVM work about using legacy or vfio attached devices, and I'm the maintainer of a DPDK PMD recently accepted upstream which requires our particular UIO driver (not maintained upstream). So I guess I could help with this effort and testing the code with our card. Of course, I can not be full time on this but I will be happy to contribute. On Fri, Dec 11, 2015 at 11:20 PM, Jan Viktorin wrote: > Hello, > > I am not involved in the vfio very much, however, I was watching some > vfio-related code in last few weeks. It looks promising to me and > IMHO it seems to the best way to bring a support of integrated Ethernet > MACs into DPDK (related to many SoCs). Unfortunately, the ARMv7 SoCs (I > know) lacks of an IOMMU... The only protection there is the TrustZone > technology but I have no idea of its support in the kernel. It's also > far from being a replacement of an IOMMU. When using FPGAs, it is > possible to put an IOMMU engine there (I've got such a prototype > somewhere in my VHDL library) but nobody will probably do use because > of saving on-chip resources. > > The X-Gene SoC (ARM 64) contains 2x 10 Gbps EMACs on the chip. I have no > idea about IOMMUs there. Thus, this platform can probably benefit of > such driver as well. The question is whether there is some interest to > have this kind of support in DPDK. > > Thus, I'd like to have the vfio/no-iommu to support the ARMv7 (otherwise > it would be effectively dead in DPDK). Unfortunately, it's not my > primary job at the moment. > > Regards > Jan > > Note: as far as I know, it is discouraged to refer to lkml.org as > it is often very slow - my case today :). > > On Fri, 11 Dec 2015 17:28:43 +0100 > Thomas Monjalon wrote: > > > Recently there were some discussions to have an upstream replacement > > for our igb_uio module. > > Several solutions were discussed (new uio driver, uio_pci_generic, vfio): > > https://lkml.org/lkml/2015/10/16/700 > > > > Alex Williamson (maintainer of VFIO driver), submitted a solution > > and was waiting some feedback. Unfortunately, nobody caught it and > > he has reverted his work: > > > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ae5515d > > > > It is an important challenge to remove our out-of-tree modules and > > especially igb_uio. It is a long way to have a standard solution > integrated > > in every distributions. > > The current cooking Linux kernel is 4.4 and will have a long term > maintenance: > > https://kernel.org/releases.html > > So it is a pity to miss this opportunity. > > > > Stephen has fixed a bug to use the IOMMU group zero: > > http://dpdk.org/browse/dpdk/commit/?id=22215f141b1 > > > > Is there someone interested to work on VFIO no-iommu and provide > > some feedbacks? > > We also need to prepare a documentation patch to explain its usage > > compared to the standard VFIO mode. > > > > Thanks > >