From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH RFC 0/5] net: L2 only interfaces Date: Tue, 25 Aug 2015 16:24:36 -0700 Message-ID: <55DCF934.8000906@gmail.com> References: <1440543015-14693-1-git-send-email-f.fainelli@gmail.com> <20150825232021.GA8482@Alexeis-MacBook-Pro-2.local> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, davem@davemloft.net, andrew@lunn.ch, linux@roeck-us.net, jiri@resnulli.us, sfeldma@gmail.com To: Alexei Starovoitov Return-path: Received: from mail-pa0-f52.google.com ([209.85.220.52]:33053 "EHLO mail-pa0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755865AbbHYX1B (ORCPT ); Tue, 25 Aug 2015 19:27:01 -0400 Received: by pacti10 with SMTP id ti10so65909795pac.0 for ; Tue, 25 Aug 2015 16:27:01 -0700 (PDT) In-Reply-To: <20150825232021.GA8482@Alexeis-MacBook-Pro-2.local> Sender: netdev-owner@vger.kernel.org List-ID: On 25/08/15 16:20, Alexei Starovoitov wrote: > On Tue, Aug 25, 2015 at 03:50:10PM -0700, Florian Fainelli wrote: >> Hi all, >> >> This patch series implements a L2 only interface concept which basically denies >> any kind of IP address configuration on these interfaces, but still allows them >> to be used as configuration end-points to keep using ethtool and friends. >> >> A cleaner approach might be to finally come up with the concept of net_port >> which a net_device would be a superset of, but this still raises tons of >> questions as to whether we should be modifying userland tools to be able to >> configure/query these interfaces. During all the switch talks/discussions last >> year, it seemed to me like th L2-only interface is closest we have to a >> "network port". >> >> Comments, flames, flying tomatoes welcome! >> >> Florian Fainelli (5): >> net: add IFF_L2_ONLY flag >> net: ipv4: Skip in_dev initialization for IFF_L2_ONLY interfaces >> net: ipv6: Skip in6_dev initialization for IFF_L2_ONLY interfaces > > interesting idea! Do you know how kernel/iproute2 will react to lack of in_dev? Surprisingly pretty good so far, have not found a way to make the kernel crash ;) > No crashes I'm assuming, but what kind of errors are thrown? If you try to assign an IP address to such an interface, you get: # ifconfig gphy 192.168.1.1 ifconfig: SIOCSIFADDR: No buffer space available > imo great first step to have lightweight netdevs. +1 for 'net_port' in the future. Thanks! -- Florian