From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergio Gonzalez Monroy Subject: Re: ip_chksum not updated in ipsec-secgw application Date: Mon, 18 Jul 2016 15:25:47 +0100 Message-ID: <4f83b6a7-08ae-f1c1-9efc-e9798bba355e@intel.com> References: <82bd976f-7482-924f-a50a-649bd63d4d65@nxp.com> <4ff03933-ba75-87d4-84ec-320160c0a60f@intel.com> <11219047.piiXn93FtH@xps13> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: Akhil Goyal , dev@dpdk.org To: Thomas Monjalon Return-path: Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by dpdk.org (Postfix) with ESMTP id D00BC3237 for ; Mon, 18 Jul 2016 16:25:49 +0200 (CEST) In-Reply-To: <11219047.piiXn93FtH@xps13> 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 18/07/2016 15:09, Thomas Monjalon wrote: > 2016-07-18 14:57, Sergio Gonzalez Monroy: >> On 18/07/2016 14:53, Akhil Goyal wrote: >>> On 7/18/2016 6:50 PM, Thomas Monjalon wrote: >>>> 2016-07-18 13:57, Sergio Gonzalez Monroy: >>>>> On 18/07/2016 13:41, Akhil Goyal wrote: >>>>>> In Ipsec-secgw application, while adding the outer IP header, >>>>>> it seems that the application does not update the checksum value >>>>>> for outbound packets. This result in incorrect ip->checksum in >>>>>> the encrypted packet. >>>> [...] >>>>> It is intentional. The application is using IP checksum offload >>>> The correct behaviour is to have a software fallback (using rte_ip.h) >>>> for drivers which do not support checksum offload. >>>> But given it is just an example, it is normal to have this kind of >>>> constraint. However I think it should be explained in its doc. >>>> And a list of tested NICs would be nice to have. >>>> >>> Agreed. The driver that I was using did not enable checksum offload. >>> It is good to have a fallback option. >> That's a good point. >> So would it be enough to call out in the sample app guide that we use IP >> checksum offload and >> show a warning in case the Driver does not support such offload? > Yes > and a list of tested NICs would make it perfect :) There is no mention of specific tested hardware in the example guides, is there? I would prefer to just point to doc/guides/nics/overview.rst to check if the NIC supports IP checksum offload and in the application itself check for such capability and display a warning in case it is not supported. Sergio