From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ferruh Yigit Subject: Re: rte_kni.ko with lo_mode=lo_mode_ring Date: Fri, 2 Sep 2016 15:55:04 +0100 Message-ID: <80a235de-226a-bcac-89f8-74550c0273ce@intel.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: "dev@dpdk.org" To: "Wiles, Keith" , "Mussar, Gary" Return-path: Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by dpdk.org (Postfix) with ESMTP id 4F8614B79 for ; Fri, 2 Sep 2016 16:55:07 +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 9/2/2016 3:16 PM, Wiles, Keith wrote: > HI Gary, > > Regards, > Keith > >> On Sep 2, 2016, at 8:39 AM, Mussar, Gary wrote: >> >> The pktgen docs state that the rte_kni.ko should be loaded with lo_mode=lo_mode_ring however the source in dpdk master does not appear to understand this value. This wasn't an issue in the past since the kni code would simply disable lo_mode if you passed in an unknown value. >> >> The Ubuntu 4.4.0-36-generic kernel no longer loads the module if the passed value is not in the table of known values (the 4.4.0-34-generic kernel would still load the module). >> >> I have 2 questions: >> 1) >> Why does pktgen specify using a value for lo_mode that the source does not support? Is lo_mode_ring something that is coming but not yet submitted? > > The KNI support and kernel module is more of a DPDK issue then Pktgen, which is the application on top of DPDK. I do not know the reason lo_mode_ring is not working correctly. Look in the Maintainers file and see who maintains the KNI code. "lo_mode_ring" is not supported loopback mode, supported ones are: lo_mode_none lo_mode_fifo lo_mode_fifo_skb Please point the document with incorrect usage. > >> >> 2) >> Is the Ubuntu kernel being over aggressive in parameter checking or is this a "good" thing? If it is good, then should the pktgen docs be indicating that an unsupported value be used for lo_mode? > > I assume the Ubuntu Kernel is attempting to protect itself. Each time the kernel is updated it is a good think to recompile DPDK and the KNI kernel module or the module may not load because of a version mis-match. Yes this looks like the issue, instead of kernel version or parameter protection, kernel-module version mismatch. Please re-compile kni module. > >> >> Gary >