From patchwork Wed May 16 07:29:12 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Xu, Rosen" X-Patchwork-Id: 40088 X-Patchwork-Delegate: thomas@monjalon.net Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 065D91B3E5; Wed, 16 May 2018 09:28:33 +0200 (CEST) Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id 18B1E1B1D9; Wed, 16 May 2018 09:28:30 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 May 2018 00:28:29 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,404,1520924400"; d="scan'208";a="42193357" Received: from dpdkx8602.sh.intel.com ([10.67.110.200]) by orsmga006.jf.intel.com with ESMTP; 16 May 2018 00:28:27 -0700 From: Rosen Xu To: dev@dpdk.org Cc: anatoly.burakov@intel.com, gaetan.rivet@6wind.com, john.mcnamara@intel.com, rosen.xu@intel.com, yulong.pei@intel.com, stable@dpdk.org Date: Wed, 16 May 2018 15:29:12 +0800 Message-Id: <1526455752-147108-1-git-send-email-rosen.xu@intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1526294652-102665-1-git-send-email-rosen.xu@intel.com> References: <1526294652-102665-1-git-send-email-rosen.xu@intel.com> Subject: [dpdk-dev] [PATCH v2] doc/guides/rel_notes: Add known issue for IOMMU attributes read 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: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Linux kernel 4.10.0 iommu attribute read error Cc: stable@dpdk.org Signed-off-by: Rosen Xu v2 updates: Acked-by: John McNamara =========== - Fixed Anatoly comments --- doc/guides/rel_notes/known_issues.rst | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/doc/guides/rel_notes/known_issues.rst b/doc/guides/rel_notes/known_issues.rst index afcc2c4..716bd73 100644 --- a/doc/guides/rel_notes/known_issues.rst +++ b/doc/guides/rel_notes/known_issues.rst @@ -714,3 +714,28 @@ igb_uio can not be used when running l3fwd-power **Driver/Module**: ``igb_uio`` module. + + +Linux kernel 4.10.0 iommu attribute read error +---------------------------------------------- + +**Description**: + When VT-d is enabled (``iommu=pt intel_iommu=on``), reading IOMMU attributes from + /sys/devices/virtual/iommu/dmarXXX/intel-iommu/cap on Linux kernel 4.10.0 error. + This bug is fixed in `Linux commmit a7fdb6e648fb + `_, + This bug is introduced in `Linux commmit 39ab9555c241 + `_, + +**Implication**: + 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.