From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: Re: [PATCH 1/3] ifb: make device count build-time configurable Date: Tue, 12 Jan 2016 16:19:58 +0100 Message-ID: <5695199E.2040303@iogearbox.net> References: <1452599804-27284-1-git-send-email-lkundrak@v3.sk> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "David S. Miller" , Jamal Hadi Salim To: Lubomir Rintel Return-path: Received: from www62.your-server.de ([213.133.104.62]:36855 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965048AbcALPUB (ORCPT ); Tue, 12 Jan 2016 10:20:01 -0500 In-Reply-To: <1452599804-27284-1-git-send-email-lkundrak@v3.sk> Sender: netdev-owner@vger.kernel.org List-ID: On 01/12/2016 12:56 PM, 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. Thanks for the set in general, good to see it fixed! > Signed-off-by: Lubomir Rintel > --- [...] > +config IFB_COUNT > + int "Number of ifb devices to pre-create at init time" > + depends on IFB > + default 3 Should that not be 2? > + help > + Static number of ifb devices to be unconditionally pre-created > + at init time. > + > + This default value can be overwritten on the kernel command > + line or with module-parameter ifb.numifbs. > + > + The historic default is 3. If a mid-2007 version of iproute2 > + is used (v2.6.23 or later), it can be set to 0, since needed > + ifb devices can be dynamically allocated via rtnetlink. [...] > -static int numifbs = 2; ^^^^^^^^^^^^ > +static int numifbs = CONFIG_IFB_COUNT; > module_param(numifbs, int, 0); > MODULE_PARM_DESC(numifbs, "Number of ifb devices");