From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Lunn Subject: Re: [RFC v2, net-next, PATCH 0/4] Add switchdev on TI-CPSW Date: Mon, 18 Jun 2018 19:30:25 +0200 Message-ID: <20180618173025.GF5865@lunn.ch> References: <1528974690-31600-1-git-send-email-ilias.apalodimas@linaro.org> <20180618150424.GA5865@lunn.ch> <20180618160418.GA25068@apalos> <20180618162836.GD5865@lunn.ch> <20180618164602.GA26411@apalos> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, grygorii.strashko@ti.com, ivan.khoronzhuk@linaro.org, nsekhar@ti.com, jiri@resnulli.us, ivecera@redhat.com, f.fainelli@gmail.com, francois.ozog@linaro.org, yogeshs@ti.com, spatton@ti.com, Jose.Abreu@synopsys.com To: Ilias Apalodimas Return-path: Received: from vps0.lunn.ch ([185.16.172.187]:35603 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755035AbeFRRa3 (ORCPT ); Mon, 18 Jun 2018 13:30:29 -0400 Content-Disposition: inline In-Reply-To: <20180618164602.GA26411@apalos> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, Jun 18, 2018 at 07:46:02PM +0300, Ilias Apalodimas wrote: > On Mon, Jun 18, 2018 at 06:28:36PM +0200, Andrew Lunn wrote: > > > Yes, if the CPU port is added on the VLAN then unregistered multicast traffic > > > (and thus IGMP joins) will reach the CPU port and everything will work as > > > expected. I think we should not consider this as a "problem" as long as it's > > > descibed properly in Documentation. This switch is excected to support this. > > > > Back to the two e1000e. What would you expect to happen with them? > > Either IGMP snooping needs to work, or your don't do snooping at > > all. > That's a different use case I disagree. That is the exact same use case. I add ports to a bridge and i expect the bridge to either do IGMP snooping, or just forward all multicast. That is the users expectations. That is how the Linux network stack works. If the hardware has limitations you want to try to hide them from the user. > > So by default, it just needs to work. You can give the user the option > > to shoot themselves in the foot, but they need to actively pull the > > trigger to blow their own foot off. > Yes it does by default. I don't consider it "foot shooting" though. > If we stop thinking about switches connected to user environments I never think about switches. I think about a block of acceleration hardware, which i try to offload Linux networking to. And if the hardware cannot accelerate Linux network functions properly, i don't try to offload it. That way it always operates in the same way, and the user expectations are clear. Andrew