From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 7A830727 for ; Mon, 26 Jun 2017 05:54:56 +0000 (UTC) Received: from smtp.nue.novell.com (smtp.nue.novell.com [195.135.221.5]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 727CB180 for ; Mon, 26 Jun 2017 05:54:55 +0000 (UTC) To: Matthew Wilcox References: From: Hannes Reinecke Message-ID: <85e0d92f-628b-8c10-30c3-d8b28b8a1dcf@suse.com> Date: Mon, 26 Jun 2017 07:54:52 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Cc: ksummit-discuss@lists.linuxfoundation.org Subject: Re: [Ksummit-discuss] [TECH TOPIC] (PCI) driver rebinding List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 06/25/2017 11:38 PM, Matthew Wilcox wrote: > Is udev the solution here? > (Top posting; tsk. Probably the new job environment :-) > Have ->probe do common initialisation and return success. Then udev says > something to the driver to make it choose one or the other modes. > Which would be option 2 from my proposal. (And, incidentally, is what zSeries does.) Plus you essentially spanning off your own bus from the PCI device, which would solve the PCI binding problem. But you just delegated the problem one level higher, as you then have to configure your private bus. So I don't think it solves the underlying problem, namely how to get the configuration to the driver. Another problem here is that you rely on udev to do the binding, ie you have to configure the device first before it can used. Which requires the use of an initrd, and I'm not sure if everyone can agree to that. Or come up with a commandline parameter instructing the driver on which devices to bind. So it's far from being clear-cut; hence this proposal. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@suse.com +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)