From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1424420AbcFHTm5 (ORCPT ); Wed, 8 Jun 2016 15:42:57 -0400 Received: from lb1-smtp-cloud6.xs4all.net ([194.109.24.24]:37004 "EHLO lb1-smtp-cloud6.xs4all.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1423505AbcFHTmz (ORCPT ); Wed, 8 Jun 2016 15:42:55 -0400 Message-ID: <1465414960.12598.29.camel@tiscali.nl> Subject: Re: [PATCH v3 1/2] checkpatch: add Kconfig 'default n' test From: Paul Bolle To: Yingjoe Chen , Andy Whitcroft Cc: Joe Perches , Andrew Morton , linux-kernel@vger.kernel.org, srv_heupstream@mediatek.com, Andi Kleen Date: Wed, 08 Jun 2016 21:42:40 +0200 In-Reply-To: <1465305402.26524.6.camel@mtksdaap41> References: <1465017040-12777-1-git-send-email-yingjoe.chen@mediatek.com> <1465231395.25087.13.camel@perches.com> <20160606191047.GK18360@brain> <1465305402.26524.6.camel@mtksdaap41> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.16.5 (3.16.5-3.fc22) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On di, 2016-06-07 at 21:16 +0800, Yingjoe Chen wrote: > On Mon, 2016-06-06 at 20:10 +0100, Andy Whitcroft wrote: > > > Is it obvious that a Kconfig has "default n" ? > > > This seems to work, but is this useful? > > While sending patch for upstream, I saw maintainers request it to be > removed. So I think it might worth adding check to it. > Some examples from google: > > http://lists.infradead.org/pipermail/linux-arm-kernel/2012-September/1 > 20733.html > https://lkml.org/lkml/2013/3/16/153 > https://lkml.org/lkml/2016/5/23/657 There's one rather subtle case where setting "default n" is, sort of, useful. See lkml.kernel.org/r/<178407860.0zoJnDfCo1@tacticalops> . (I seem to remember disagreeing here. Ie, in my view setting defaults for a specific Kconfig symbol at two different places is confusing at best. People probably weren't convinced by my objections. I also remember diving into this by looking at the various places where a Kconfig symbol was being set twice. I must have ended that endeavor when it became clear to me I was't making any progress.) Even though there's a corner case where "default n" is useful, it could still be worth to add a checkpatch check that warns about it. But I can't say I feel strongly about this either way. Paul Bolle