From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next 1/1] net/smc: add SMC rendezvous protocol Date: Wed, 11 Oct 2017 14:06:52 -0700 (PDT) Message-ID: <20171011.140652.272274136617199385.davem@davemloft.net> References: <20171010141419.88190-1-ubraun@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-s390@vger.kernel.org, jwi@linux.vnet.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, raspl@linux.vnet.ibm.com, hwippel@linux.vnet.ibm.com To: ubraun@linux.vnet.ibm.com Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:36678 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752631AbdJKVGx (ORCPT ); Wed, 11 Oct 2017 17:06:53 -0400 In-Reply-To: <20171010141419.88190-1-ubraun@linux.vnet.ibm.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Ursula Braun Date: Tue, 10 Oct 2017 16:14:19 +0200 > The goal of this patch is to leave common TCP code unmodified. Thus, > it uses netfilter hooks to intercept TCP SYN and SYN/ACK > packets. For outgoing packets originating from SMC sockets, the > experimental option is added. For inbound packets destined for SMC > sockets, the experimental option is checked. I think this really isn't going to pass. It's a user experience nightmare when the kernel inserts and deletes filtering rules outside of what the user configures on their system. This approach was also considerd for ipv6 ILA, and the same pushback was given. Why not add support for these new options as a normal TCP socket option based feature? Then normal userspace as well as the SMC stack can make use of it.