From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ferruh Yigit Subject: Re: [PATCH v2] igb_uio: fix possible mmap failure for Linux > v4.3 Date: Fri, 1 Jul 2016 16:54:48 +0100 Message-ID: <57769248.3010209@intel.com> References: <1467372912-31113-1-git-send-email-ferruh.yigit@intel.com> <1467385678-16205-1-git-send-email-ferruh.yigit@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: Stephen Hemminger To: "De Lara Guarch, Pablo" , "dev@dpdk.org" Return-path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id 9D0A319F5 for ; Fri, 1 Jul 2016 17:54:52 +0200 (CEST) In-Reply-To: List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 7/1/2016 4:52 PM, De Lara Guarch, Pablo wrote: > Hi Ferruh, > >> -----Original Message----- >> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Ferruh Yigit >> Sent: Friday, July 01, 2016 4:08 PM >> To: dev@dpdk.org >> Cc: Stephen Hemminger >> Subject: [dpdk-dev] [PATCH v2] igb_uio: fix possible mmap failure for Linux > >> v4.3 >> >> mmap the iomem range of the PCI device fails for kernels that >> enabled CONFIG_IO_STRICT_DEVMEM option: >> >> EAL: pci_map_resource(): >> cannot mmap(39, 0x7f1c51800000, 0x100000, 0x0): >> Invalid argument (0xffffffffffffffff) >> >> CONFIG_IO_STRICT_DEVMEM is introduced in Linux v4.4 and not enabled >> by default: > > This was introduced in kernel 4.5 (change the title as well ;)) "git describe" mislead me but you are right, I will update $ git describe 90a545e v4.4-rc5-2-g90a545e Thanks > >> Linux commit: 90a545e restrict /dev/mem to idle io memory ranges >> >> As a workaround igb_uio can stop reserving PCI memory resources, from >> kernel point of view iomem region looks like idle and mmap works >> again. This matches uio_pci_generic usage. >> >> With this update device iomem range is not protected against any >> other kernel drivers or userspace access. But this shouldn't >> be a problem for dpdk usage module since purpose of the igb_uio >> module is to provide userspace access. >> >> Fixes: af75078fece3 ("first public release") >> Signed-off-by: Ferruh Yigit >