From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: ip_chksum not updated in ipsec-secgw application Date: Mon, 18 Jul 2016 16:09:23 +0200 Message-ID: <11219047.piiXn93FtH@xps13> References: <82bd976f-7482-924f-a50a-649bd63d4d65@nxp.com> <4ff03933-ba75-87d4-84ec-320160c0a60f@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: Akhil Goyal , dev@dpdk.org To: Sergio Gonzalez Monroy Return-path: Received: from mail-wm0-f41.google.com (mail-wm0-f41.google.com [74.125.82.41]) by dpdk.org (Postfix) with ESMTP id 7DCCA2C6E for ; Mon, 18 Jul 2016 16:09:25 +0200 (CEST) Received: by mail-wm0-f41.google.com with SMTP id f126so105223451wma.1 for ; Mon, 18 Jul 2016 07:09:25 -0700 (PDT) In-Reply-To: <4ff03933-ba75-87d4-84ec-320160c0a60f@intel.com> 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" 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 :)