From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ivan Vecera Subject: Re: [RFC v2, net-next, PATCH 4/4] net/cpsw_switchdev: add switchdev mode of operation on cpsw driver Date: Thu, 21 Jun 2018 14:19:55 +0200 Message-ID: <033dd1bc-0401-a058-5283-4938ac39f701@redhat.com> References: <1528974690-31600-1-git-send-email-ilias.apalodimas@linaro.org> <1528974690-31600-5-git-send-email-ilias.apalodimas@linaro.org> <20180618161627.GC5865@lunn.ch> <20180618201940.GA5890@apalos> <671c83ea-6227-cc09-e604-14cfa6804726@redhat.com> <20180620175128.GA27235@apalos> <20180620180342.GA28303@apalos> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: Andrew Lunn , netdev@vger.kernel.org, grygorii.strashko@ti.com, ivan.khoronzhuk@linaro.org, nsekhar@ti.com, jiri@resnulli.us, francois.ozog@linaro.org, yogeshs@ti.com, spatton@ti.com, Jose.Abreu@synopsys.com To: Ilias Apalodimas , Florian Fainelli Return-path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:39050 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933149AbeFUMUA (ORCPT ); Thu, 21 Jun 2018 08:20:00 -0400 In-Reply-To: <20180620180342.GA28303@apalos> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 20.6.2018 20:03, Ilias Apalodimas wrote: > Hi Florian, > > On Wed, Jun 20, 2018 at 10:58:26AM -0700, Florian Fainelli wrote: >> On 06/20/2018 10:51 AM, Ilias Apalodimas wrote: >>> Hello Ivan, >>> On Wed, Jun 20, 2018 at 02:56:48PM +0200, Ivan Vecera wrote: >>>> On 18.6.2018 22:19, Ilias Apalodimas wrote: >>>>> Jiri proposed using devlink, which makes sense, but i am not sure it's >>>>> applicable on this patchset. This will change the driver completely and will >>>>> totally break backwards compatibility. >>>> >>>> Another good reason for a new driver. >>>> >>>> I. >>> This is actually conflicting at least to my understanding. Jiri proposed using >>> devlink was used as an alternative method to enable a new mode instead of >>> adding it on a .config option. A new driver wouldn't have a need for that right? >> >> Correct, with a new driver would likely behave correctly upon being >> probed such that you could have your switch ports act as normal network >> devices from which you could run IP-config and do NFS boot. > The current driver also does NFS properly and the 2 ethernet ports act as normal > network interfaces. The NFS section in the cover letter > is to cover the cases were users running on NFS need to change the running > switch configuration(starting from adding the 2 interfaces on a bridge). > Since iproute2 is located on the NFS filesystem the moment > network connectivity is lost, you loose the ability to perform further > configuration and in certian configuration scenarios render the device > unusable. Yes, with a new driver you can drop NFS-boot hack you mentioned in cover letter. All configuration is done during driver probe and thus prior NFS mount. Only thing you loose with a new driver is backward compatibility but the question is: DO you really need it? Ivan