From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <vincent.jardin@6wind.com> Received: from mail-wm0-f45.google.com (mail-wm0-f45.google.com [74.125.82.45]) by dpdk.org (Postfix) with ESMTP id 480008E7B for <dev@dpdk.org>; Fri, 11 Dec 2015 23:12:34 +0100 (CET) Received: by mail-wm0-f45.google.com with SMTP id c201so91090777wme.0 for <dev@dpdk.org>; Fri, 11 Dec 2015 14:12:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=6wind-com.20150623.gappssmtp.com; s=20150623; h=message-id:date:from:organization:user-agent:mime-version:to:cc :subject:references:in-reply-to:content-type :content-transfer-encoding; bh=3XFxDzFWl9AM1UscYD+infAZ8UfB962e+y5+gOzT5eY=; b=zZkNk7XqE0zFJX+NxJ3am++HJpS8kKus+ab84+vG43Z7+FKXfl8Jv2QoLsKdDgKPVg BsFSoYF3k/CyMDbVB8awNpel2BzNHqxM7povNxgATp1SgnpFqJv5yf1W+pMpzPbbkRZH NyRxtzFaDbXnAk693ZRjTiljTspMeI1PgYpp8V5yzoBokHrInh24wDz9s18bgkjhSXmV 5FAqEd9dPiJslwlH2nqXe0ARdiKpKxayCYbnbF09MS8wKVqFLLb2O1Y68d7bLlW0ph/F tBXBVHyPWctOnerwUPbQYVJpUrq4/Y62jOqv6iJYais+l/H6CDRIvovLY6rfzdlJvqLa 5OCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:message-id:date:from:organization:user-agent :mime-version:to:cc:subject:references:in-reply-to:content-type :content-transfer-encoding; bh=3XFxDzFWl9AM1UscYD+infAZ8UfB962e+y5+gOzT5eY=; b=NHs/HQzhZ4Vxk+rkGiMaw5x3CuROJJI5+9N6bpibjKvDsDLpShFErwlGpHnMVGR806 fK+iaKcj/gSNn3/rU6No1iCFrJBiLC1F3GfqHHG7DzIhlmhBTowvfBBMwps1bj5cLC/Y NN/KkYROCQ5lJk6f6QO01yChJ0mfnqB6J7sclFvdHEyPuAWx+ENtI63tR3isE+cc1AcL obq2dhkrex9ksVd2Bg+63qbfE+stNSzSsqrG2ub0x0y4Y2Zhdfkm/rwC5nQVkUoB/QyW stPZA1kpCPvSDGqHmoq75bOzfdll9nP0Pnxvl1ggnaskebXYJqLxd2+qXByJtdSiu4M3 ICoA== X-Gm-Message-State: ALoCoQkw9nJb6W211eXvMuwaB7Wjk5g+DEMSX7LKzGBzx+FAsKLU2pj3w1DfTnL/n9vYB9zIY4YPctgIi95ZQzMVrtPnSMvJAA== X-Received: by 10.194.204.232 with SMTP id lb8mr26611334wjc.112.1449871954137; Fri, 11 Dec 2015 14:12:34 -0800 (PST) Received: from saturne.dev.6wind.com ([2a01:e35:8a8e:1b70:226:b9ff:fec7:e133]) by smtp.gmail.com with ESMTPSA id l184sm1021734wmf.6.2015.12.11.14.12.33 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 11 Dec 2015 14:12:33 -0800 (PST) Message-ID: <566B4A50.9090607@6wind.com> Date: Fri, 11 Dec 2015 23:12:32 +0100 From: Vincent JARDIN <vincent.jardin@6wind.com> Organization: www.6wind.com User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: dev@dpdk.org, Alex Williamson <alex.williamson@redhat.com> References: <60420822.AbcfvjLZCk@xps13> In-Reply-To: <60420822.AbcfvjLZCk@xps13> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit 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 <dev.dpdk.org> List-Unsubscribe: <http://dpdk.org/ml/options/dev>, <mailto:dev-request@dpdk.org?subject=unsubscribe> List-Archive: <http://dpdk.org/ml/archives/dev/> List-Post: <mailto:dev@dpdk.org> List-Help: <mailto:dev-request@dpdk.org?subject=help> List-Subscribe: <http://dpdk.org/ml/listinfo/dev>, <mailto:dev-request@dpdk.org?subject=subscribe> X-List-Received-Date: Fri, 11 Dec 2015 22:12:34 -0000 Thanks Thomas for putting back this topic. Alex, I'd like to hear more about the impacts of "unsupported": https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=033291eccbdb1b70ffc02641edae19ac825dc75d Use of this mode, specifically binding a device without a native IOMMU group to a VFIO bus driver will taint the kernel and should therefore not be considered supported. It means that we get ride of uio; so it is a nice code cleanup: but why would VFIO/NO IOMMU be better if the bottomline is "unsupported"? Thank you, Vincent On 11/12/2015 17:28, 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 >