From mboxrd@z Thu Jan 1 00:00:00 1970 From: Edward Cree Subject: Re: Generic TSO (was Re: [net-next PATCH 0/2] GENEVE/VXLAN: Enable outer Tx checksum by default) Date: Fri, 11 Mar 2016 19:59:23 +0000 Message-ID: <56E3239B.7080009@solarflare.com> References: <20160219191806.15687.37621.stgit@localhost.localdomain> <56E31A89.9020602@solarflare.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Linux Kernel Network Developers To: Tom Herbert Return-path: Received: from nbfkord-smmo01.seg.att.com ([209.65.160.76]:8052 "EHLO nbfkord-smmo01.seg.att.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751564AbcCKUMF (ORCPT ); Fri, 11 Mar 2016 15:12:05 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 11/03/16 19:57, Tom Herbert wrote: > On Fri, Mar 11, 2016 at 11:20 AM, Edward Cree wrote: >> Tom, >> >> Are you planning to / working on implementing this? If not, I might have a >> crack at it; I've talked to our firmware guys and (provisionally) we think >> we can support it in current sfc hardware. >> Or were there any blocking problems raised in the thread? My understanding >> of the IP ID issue was that it only matters for the inner frame, because >> the rest aren't TCP (so hopefully no-one is doing SLHC on them). But I may >> have missed something. >> > Right, then the interface would need to just include the offset of the > IP ID. But doesn't this break using LCO with GSO though-- i.e. the > outer checksum and inner checksum still need to be updated per packet > so we need to tell device where outer checksum(s) is. No, outer checksum shouldn't change: IP ID is protected by inner IP header checksum, which device will edit. No? -Ed