From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 1/3] ifb: make device count build-time configurable Date: Tue, 12 Jan 2016 15:54:40 -0500 (EST) Message-ID: <20160112.155440.538873882796833417.davem@davemloft.net> References: <1452599804-27284-1-git-send-email-lkundrak@v3.sk> <5694F7BA.3040402@mojatatu.com> <20160112104437.0e1a841b@xeon-e3> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: jhs@mojatatu.com, lkundrak@v3.sk, netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: stephen@networkplumber.org Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:53965 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754102AbcALUym (ORCPT ); Tue, 12 Jan 2016 15:54:42 -0500 In-Reply-To: <20160112104437.0e1a841b@xeon-e3> Sender: netdev-owner@vger.kernel.org List-ID: From: Stephen Hemminger Date: Tue, 12 Jan 2016 10:44:37 -0800 > On Tue, 12 Jan 2016 07:55:22 -0500 > Jamal Hadi Salim wrote: > >> On 16-01-12 06:56 AM, Lubomir Rintel wrote: >> > The devices can be created at run-time for quite some time already and the >> > load-time device creation collides with attempts to create the device of >> > the same name: >> > >> > # rmmod ifb >> > # ip link add ifb0 type ifb >> > RTNETLINK answers: File exists >> > >> > This is pretty much the same situation as was with the block loop devices >> > which was solved by adding a build-time configuration that the >> > distributions could use as they deem fit while keeping the default for >> > compatibility. >> > >> > Let's do that here as well. >> > >> > Signed-off-by: Lubomir Rintel >> >> I guess module options are frowned upon. so: > > I would prefer that this were done with a module parameter, the same as dummy. > Only developers build their own configured kernels. Having the value set later > at module load time is preferable. I like this even less, it means tools behave significantly differently based upon what module options were passed to the kernel. Module options really should not change kernel behavior like this..