From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7E419C2D0F2 for ; Tue, 31 Mar 2020 17:10:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E22720848 for ; Tue, 31 Mar 2020 17:10:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ejCKGv9e" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731238AbgCaRKy (ORCPT ); Tue, 31 Mar 2020 13:10:54 -0400 Received: from mail-ot1-f66.google.com ([209.85.210.66]:44050 "EHLO mail-ot1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726194AbgCaRKx (ORCPT ); Tue, 31 Mar 2020 13:10:53 -0400 Received: by mail-ot1-f66.google.com with SMTP id a49so22764732otc.11 for ; Tue, 31 Mar 2020 10:10:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=qHYDmZrgq5jmEkRfovldh3Vm9VQlL40sufsyBZ8bEao=; b=ejCKGv9ewqzPDwu36dgEf76BAdc6P8/FNIHvqlRJ2NbFTsqobiYJueIPM1QZi0OCCQ mbU1B6WSb811ZFiG9JOqTsYC1SHqnNkP67uF97SvOhv96tkShJMN5PdECEv/UVHWpBbe dmopibqZGT8YOlWB1Mxjj8B8vSeGI+adpgikk5ZFFX19jP5gQEyzgvSeCkR+ruYYKmOR 1nHq5goBe3vvatRr2t6ArsKapoHRzQb/Dp8xUl9h++ZuJuyY81r7fl+m1ecyqBeAUMb9 U7tiQZCEeGGDdpZ4SYSLIDyZTmrECoB9X/A+YpKZrNIyVhGzFEbffqrR2St0hFC6aHil 3G0g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=qHYDmZrgq5jmEkRfovldh3Vm9VQlL40sufsyBZ8bEao=; b=R6NUywrKXI8Ul0TJSJoMYaffJTNXMBhLAb20Pzilb/2RldCJxPc2XDzgq6vMwpjeGh i140OeVypJ72vmzj3YLud3NV8t0d/tkUM7ohkAbrdiTXbZUjAhy508AvCvmM3lm9MPN5 NSVLMUAZSrpQ5mJUAFL/YLQor8urnWA0/pBuNirHYnQp7MQLLmdU73QUTehp2n1wvcK7 8EFvPfvm4BzrPlzXxsF+1LFHivMbo1YeZniNJT06tEfWsKbKX/wtFM3y+O3WnR7avS/z 3K6/okFzIJfR2kzFPI7HY3wEfnYK+ZTzEzzYAM8TIV32cRjaXkpfkwzULTGevh8TRJ1x r3tg== X-Gm-Message-State: ANhLgQ3io16bfmPXxC2JrAxky1vjqKpB4AoOTtBpPX1Cgu3+oct4Jb6V 6ivOp3O497n2XHZZz+hu6fui29qo/hQ7gJWQMgL8kg== X-Google-Smtp-Source: ADFU+vvG/KSouwa/5JXn2S/dDVOQi5q+3SzbGyUUkrqFLoZCxv6KzvHR1l+yj5t93H1llPNa0r7/9yF4i0utZTLMJIE= X-Received: by 2002:a05:6830:1ac1:: with SMTP id r1mr9669891otc.139.1585674651276; Tue, 31 Mar 2020 10:10:51 -0700 (PDT) MIME-Version: 1.0 References: <20200222014038.180923-1-saravanak@google.com> <20200222014038.180923-6-saravanak@google.com> In-Reply-To: From: Saravana Kannan Date: Tue, 31 Mar 2020 10:10:15 -0700 Message-ID: Subject: Re: [PATCH v1 5/5] of: property: Delete of_devlink kernel commandline option To: Geert Uytterhoeven Cc: Jonathan Corbet , Greg Kroah-Hartman , "Rafael J. Wysocki" , Ard Biesheuvel , Rob Herring , Frank Rowand , Len Brown , Android Kernel Team , "open list:DOCUMENTATION" , Linux Kernel Mailing List , linux-efi , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , ACPI Devel Maling List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 31, 2020 at 5:20 AM Geert Uytterhoeven wrote: > > Hi Saravana, > > On Sat, Feb 22, 2020 at 2:41 AM Saravana Kannan wrote: > > With the addition of fw_devlink kernel commandline option, of_devlink is > > redundant and not useful anymore. So, delete it. > > > > Signed-off-by: Saravana Kannan > > Thanks for your patch! > > This is now commit e94f62b7140fa3da ("of: property: Delete of_devlink > kernel commandline option") upstream. > > > --- a/Documentation/admin-guide/kernel-parameters.txt > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > @@ -3299,12 +3299,6 @@ > > This can be set from sysctl after boot. > > See Documentation/admin-guide/sysctl/vm.rst for details. > > > > - of_devlink [OF, KNL] Create device links between consumer and > > - supplier devices by scanning the devictree to infer the > > - consumer/supplier relationships. A consumer device > > - will not be probed until all the supplier devices have > > - probed successfully. > > - > > ohci1394_dma=early [HW] enable debugging via the ohci1394 driver. > > See Documentation/debugging-via-ohci1394.txt for more > > info. > > While I agree with the thunk above... > > > diff --git a/drivers/of/property.c b/drivers/of/property.c > > index 15fc9315f1a7..f104f15b57fb 100644 > > --- a/drivers/of/property.c > > +++ b/drivers/of/property.c > > @@ -1299,15 +1299,9 @@ static int of_link_to_suppliers(struct device *dev, > > return ret; > > } > > > > -static bool of_devlink; > > -core_param(of_devlink, of_devlink, bool, 0); > > - > > static int of_fwnode_add_links(const struct fwnode_handle *fwnode, > > struct device *dev) > > { > > - if (!of_devlink) > > - return 0; > > - > > if (unlikely(!is_of_node(fwnode))) > > return 0; Hi Geert, > ... I have some reservations about removing the actual code. > The "of_devlink" kernel parameter was supported in v5.5 and v5.6, so > removing its support may silently break some setups. > > Is this likely to happen? As much as I'd love to see people start using this, I doubt of_devlink has been significantly adopted outside of Android yet (I'm working on making that easier :)). I'd be happy to be proven wrong though :) of_devlink/fw_devlink is mainly useful when module loading is causing ordering and clean up issues. So if deletion of of_devlink breaks anything, I'd expect it to break in obvious ways and not silently. > Do we need a compatibility fallback that warns to user to update his kernel > command line? I don't think we need to, but I'm not strongly against your suggestion either. Let us know what you think. -Saravana