From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Burakov, Anatoly" Subject: Re: [PATCH] doc/guides/rel_notes: Add known issue for IOMMU attributes read Date: Mon, 14 May 2018 18:10:01 +0100 Message-ID: <6b9962cf-1b50-0cf7-83e6-d9fe696c62bf@intel.com> References: <1526294652-102665-1-git-send-email-rosen.xu@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: gaetan.rivet@6wind.com, john.mcnamara@intel.com, yulong.pei@intel.com, stable@dpdk.org To: Rosen Xu , dev@dpdk.org Return-path: In-Reply-To: <1526294652-102665-1-git-send-email-rosen.xu@intel.com> Content-Language: en-US List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 14-May-18 11:44 AM, Rosen Xu wrote: > Read IOMMU attributes from linux kernle 4.10.0 error. s/kernle/kernel :) > > Cc: stable@dpdk.org > > Signed-off-by: Rosen Xu > --- > doc/guides/rel_notes/known_issues.rst | 21 +++++++++++++++++++++ > 1 file changed, 21 insertions(+) > > diff --git a/doc/guides/rel_notes/known_issues.rst b/doc/guides/rel_notes/known_issues.rst > index afcc2c4..74876ff 100644 > --- a/doc/guides/rel_notes/known_issues.rst > +++ b/doc/guides/rel_notes/known_issues.rst > @@ -714,3 +714,24 @@ igb_uio can not be used when running l3fwd-power > > **Driver/Module**: > ``igb_uio`` module. > + > + > +linux kernel iommu attribute read error Should this be capitalized? > +--------------------------------------- > + > +**Description**: > + Read immu attributes from /sys/devices/virtual/iommu/dmarXXX/intel-iommu/cap in linux kernel > + 4.10.0 error. That because the link between the iommu sysfs-device and the struct intel_iommu > + is no longer stored as driver-data. s/immu/IOMMU/, and i think this needs to be rewritten to something like as follows: Reading IOMMU attributes from /sys/devices/virtual/iommu/dmarXXX/intel-iommu/cap in Linux kernel 4.10.0 results in an error. This is because the link between the IOMMU sysfs-device and struct intel_iommu is no longer stored as driver-data. (i have no idea what that last sentence means, maybe someone could help provide a better explanation?) > + > +**Implication**: > + When insmod ``vfio-pci`` and running testpmd APP, it doesn't initiate properly. Should probably be reworded as follows: When binding devices to VFIO and attempting to run testpmd application, testpmd (and other DPDK applications) will not initialize. > + > +**Resolution/Workaround**: > + Use other linux kernel version. It only happens in linux kernel 4.10.0. > + > +**Affected Environment/Platform**: > + ALL OS of linux kernel 4.10.0. > + > +**Driver/Module**: > + ``vfio-pci`` module. > -- Thanks, Anatoly