From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by dpdk.org (Postfix) with ESMTP id 2988A1B1B2 for ; Wed, 16 May 2018 09:04:20 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 May 2018 00:04:19 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,404,1520924400"; d="scan'208";a="51243893" Received: from dpdkx8602.sh.intel.com ([10.67.110.200]) by orsmga003.jf.intel.com with ESMTP; 16 May 2018 00:04:19 -0700 From: Rosen Xu To: rosen.xu@intel.com Cc: stable@dpdk.org Date: Wed, 16 May 2018 15:05:06 +0800 Message-Id: <1526454306-146699-1-git-send-email-rosen.xu@intel.com> X-Mailer: git-send-email 1.8.3.1 Subject: [dpdk-stable] [PATCH v2] doc/guides/rel_notes: Add known issue for IOMMU attributes read X-BeenThere: stable@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches for DPDK stable branches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 16 May 2018 07:04:21 -0000 Linux kernel 4.10.0 iommu attribute read error Cc: stable@dpdk.org Signed-off-by: Rosen Xu v2 updates: =========== - 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. -- 1.8.3.1