From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id 764742BA3 for ; Fri, 21 Sep 2018 13:20:36 +0200 (CEST) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Sep 2018 04:20:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,284,1534834800"; d="scan'208";a="74853620" Received: from bricha3-mobl.ger.corp.intel.com ([10.237.221.107]) by orsmga007.jf.intel.com with SMTP; 21 Sep 2018 04:20:27 -0700 Received: by (sSMTP sendmail emulation); Fri, 21 Sep 2018 12:20:24 +0100 Date: Fri, 21 Sep 2018 12:20:23 +0100 From: Bruce Richardson To: "tone.zhang" Cc: dev@dpdk.org, gavin.hu@arm.com, bluca@debian.org, roszenrami@gmail.com, Honnappa.Nagarahalli@arm.com, nd@arm.com Message-ID: <20180921112023.GA2668@bricha3-MOBL.ger.corp.intel.com> References: <1536124655-27163-1-git-send-email-tone.zhang@arm.com> <1537499262-22644-1-git-send-email-tone.zhang@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1537499262-22644-1-git-send-email-tone.zhang@arm.com> Organization: Intel Research and Development Ireland Ltd. User-Agent: Mutt/1.10.1 (2018-07-13) Subject: Re: [dpdk-dev] [PATCH v4] doc: Clarify IOMMU usage with "uio_pci_generic" kernel module 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: Fri, 21 Sep 2018 11:20:36 -0000 On Fri, Sep 21, 2018 at 11:07:42AM +0800, tone.zhang wrote: > If the devices used for DPDK are bound to the "uio_pci_generic" kernel > module, the IOMMU should be disabled in order not to break the IO > transmission because of the virtual / physical address mapping. > > The patch clarifies the IOMMU configurations on both x86_64 and arm64 > systems. > > Signed-off-by: tone.zhang > --- > doc/guides/linux_gsg/linux_drivers.rst | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/doc/guides/linux_gsg/linux_drivers.rst b/doc/guides/linux_gsg/linux_drivers.rst > index 371a817..3304800 100644 > --- a/doc/guides/linux_gsg/linux_drivers.rst > +++ b/doc/guides/linux_gsg/linux_drivers.rst > @@ -48,6 +48,13 @@ be loaded as shown below: > ``vfio-pci`` kernel module rather than ``igb_uio`` or ``uio_pci_generic``. > For more details see :ref:`linux_gsg_binding_kernel` below. > > +.. note:: > + > + If the devices used for DPDK are bound to the ``uio_pci_generic`` kernel module, > + please make sure that the IOMMU is disabledi or passthrough. One can add typo ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^ > + ``intel_iommu=off`` or ``amd_iommu=off`` or ``intel_iommu=on iommu=pt``in GRUB > + command line on x86_64 systems, or add ``iommu.passthrough=1`` on arm64 system. > + > Since DPDK release 1.7 onward provides VFIO support, use of UIO is optional > for platforms that support using VFIO. > Acked-by: Bruce Richardson