From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ursula Braun Subject: Re: [PATCH net-next 1/1] net/smc: add SMC rendezvous protocol Date: Thu, 12 Oct 2017 12:48:04 +0200 Message-ID: References: <20171010141419.88190-1-ubraun@linux.vnet.ibm.com> <20171011.140652.272274136617199385.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 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: David Miller Return-path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:34760 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752620AbdJLKsL (ORCPT ); Thu, 12 Oct 2017 06:48:11 -0400 Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v9CAiDWL140448 for ; Thu, 12 Oct 2017 06:48:11 -0400 Received: from e06smtp10.uk.ibm.com (e06smtp10.uk.ibm.com [195.75.94.106]) by mx0a-001b2d01.pphosted.com with ESMTP id 2dj3byjgmy-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 12 Oct 2017 06:48:11 -0400 Received: from localhost by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 12 Oct 2017 11:48:08 +0100 In-Reply-To: <20171011.140652.272274136617199385.davem@davemloft.net> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 10/11/2017 11:06 PM, David Miller wrote: > 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. > Do you mean a solution like https://www.mail-archive.com/netdev@vger.kernel.org/msg71321.html https://www.mail-archive.com/netdev@vger.kernel.org/msg71324.html with a new smc_rendezvous TCP socket option as trigger?