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 938BF2BA8 for ; Fri, 1 Jul 2016 12:23:26 +0200 (CEST) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga102.fm.intel.com with ESMTP; 01 Jul 2016 03:23:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,556,1459839600"; d="scan'208";a="727854261" Received: from irsmsx152.ger.corp.intel.com ([163.33.192.66]) by FMSMGA003.fm.intel.com with ESMTP; 01 Jul 2016 03:23:23 -0700 Received: from irsmsx103.ger.corp.intel.com ([169.254.3.240]) by IRSMSX152.ger.corp.intel.com ([169.254.6.247]) with mapi id 14.03.0248.002; Fri, 1 Jul 2016 11:21:36 +0100 From: "Mcnamara, John" To: "dev@dpdk.org" Thread-Topic: Issue with igb_uio in Fedora 24 Thread-Index: AdHTgeu4MrDIw6CuTEWVm8rIPsmOSw== Date: Fri, 1 Jul 2016 10:21:35 +0000 Message-ID: Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ctpclassification: CTP_IC x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiYjE5MDM1N2YtM2JmZS00ZDFiLTlhY2MtNGE5YzM1ODNkMWE0IiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE1LjkuNi42IiwiVHJ1c3RlZExhYmVsSGFzaCI6IjFGZzZNK1NvdlVCdjBXMDY3RVFcL0tsVEV1NXl3NmRBakdcL01La0JqcXREZz0ifQ== x-originating-ip: [163.33.239.180] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: [dpdk-dev] Issue with igb_uio in Fedora 24 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 01 Jul 2016 10:23:27 -0000 Hi, We have seen an issue when using the igb_uio module in Fedora 24. However, it relates to kernel 4.5+ so it could occur in other distros/oses. The issue occurs after binding a nic to igb_uio: # ./tools/dpdk_nic_bind.py -b igb_uio 0000:03:00.0 # ./x86_64-native-linuxapp-gcc/app/test EAL: Detected 8 lcore(s) EAL: Probing VFIO support... PMD: bnxt_rte_pmd_init() called for (null) EAL: PCI device 0000:03:00.0 on NUMA socket -1 EAL: probe driver: 8086:1533 rte_igb_pmd EAL: pci_map_resource(): cannot mmap(39, 0x7f1c51800000, 0x100000, 0x0): Invalid argument (0xffffffffffffffff) EAL: Error - exiting with code: 1 Cause: Requested device 0000:03:00.0 cannot be used =20 The issue is exposed when the kernel is compiled with option CONFIG_IO_STRICT_DEVMEM turned on. This option is new from kernel 4.5 and is on by default in Fedora 24: config IO_STRICT_DEVMEM bool "Filter I/O access to /dev/mem" depends on STRICT_DEVMEM ---help--- If this option is disabled, you allow userspace (root) access to all io-memory regardless of whether a driver is actively using that range. Accidental access to this is obviously disastrous, but specific access can be used by people debugging kernel drivers. If this option is switched on, the /dev/mem file only allows userspace access to *idle* io-memory ranges (see /proc/iomem) This may break traditional users of /dev/mem (dosemu, legacy X, etc...) if the driver using a given range cannot be disabled. If in doubt, say Y. This issue doesn't occur with uio_pci_generic. John