From mboxrd@z Thu Jan 1 00:00:00 1970 From: Masahiro Yamada Subject: Re: linux-next: build warning after merge of the net-next tree Date: Fri, 20 Jul 2018 08:19:34 +0900 Message-ID: References: <20180719120447.6e7ba23d@canb.auug.org.au> <20180719152940.0720e9c1@canb.auug.org.au> <6dabf12b-e3db-dfe8-101c-02772039e21a@roeck-us.net> <20180720080906.7a30c573@canb.auug.org.au> <20180719223521.GA30287@roeck-us.net> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20180719223521.GA30287@roeck-us.net> Sender: linux-kernel-owner@vger.kernel.org To: Guenter Roeck Cc: Stephen Rothwell , David Miller , Networking , Linux-Next Mailing List , Linux Kernel Mailing List , Andrew Lunn List-Id: linux-next.vger.kernel.org 2018-07-20 7:35 GMT+09:00 Guenter Roeck : > On Fri, Jul 20, 2018 at 08:09:06AM +1000, Stephen Rothwell wrote: >> Hi Guenter, >> >> On Thu, 19 Jul 2018 06:49:01 -0700 Guenter Roeck wrote: >> > >> > On 07/18/2018 10:29 PM, Stephen Rothwell wrote: >> > > >> > > On Wed, 18 Jul 2018 20:52:56 -0700 Guenter Roeck wrote: >> > >> >> > >> On 07/18/2018 07:04 PM, Stephen Rothwell wrote: >> > >>> >> > >>> After merging the net-next tree, today's linux-next build (x86_64 >> > >>> allmodconfig) produced this warning: >> > >>> >> > >>> * >> > >>> * Restart config... >> > >>> * >> > >>> .... >> > >>> >> > >>> This is output by my "make allmodconfig" and only started after merging >> > >>> the net-next tree today. It has continued for further merges/builds. >> > >>> >> > >>> I suspect commit >> > >>> >> > >>> 1323061a018a ("net: phy: sfp: Add HWMON support for module sensors") >> > >>> >> > >>> which added an "imply" clause. >> > >>> >> > >> I thought "imply" was better than "depends on HWMON || HWMON=n", but maybe >> > >> not. Is that a caveat when using "imply", and does it mean that "imply" >> > >> should better not be used ? >> > > >> > > I don't know, sorry. It was just my best guess from what I could see >> > > had changed. >> > > >> > > I wonder if it makes a difference that I am doing my "make >> > > allmodconfig" on top of a previous "make allmodconfig" and some symbols >> > > are marked as "NEW" (though they are not symbols related to the changes >> > > that happened during the net-next tree merge)? >> > > >> > >> > I tried to reproduce the problem, but I don't see the message. >> > >> > What I do see, though, is that "make allmodconfig" on a clean tree, >> > followed by "make menuconfig", results in configuration changes. >> > Specifically, >> > >> > > CONFIG_ARC_EMAC_CORE=m >> > > CONFIG_ARC_EMAC=m >> > > CONFIG_EMAC_ROCKCHIP=m >> > >> > is removed by menuconfig, and a large number of "# ... is not set" >> > configuration lines are added. Weird and bad, since several of the >> > disabled configurations _should_ be enabled by "make allmodconfig", >> > and a large number of hwmon drivers are affected. Bisect does point >> > to "net: phy: sfp: Add HWMON support for module sensors", meaning >> > "imply hwmon" does have severe side effects and can not be used. >> > >> > I'll try to find a fix. >> >> OK, my mistake, the "make allmodconfig" works, the following "make" >> causes the config restart. (I am actually doing cross builds and using >> an external object directory, in case that matters.) >> >> I removed the "imply HWMON" line added by the above commit and the >> problem went away. Also, using "depends on HWMON || HWMON=n" instead >> of the imply fixes it. > > Yes, replacing imply with the dependency is what I did in the fixup patch. > Sorry, I should have copied you: https://patchwork.kernel.org/patch/10534925/ > > It is a bit different - imply was supposed to enforce HWMON={y,n} if SFP=y, > and the depends line enforces SFP={n,m} if HWMON=m. I have no idea why > imply doesn't work, but I think I'll stay away from it in the future. > > Guenter Hmm, this could be a Kconfig bug. I will take a look. BTW, 'depends on HWMON || HWMON=n' is pointless because it is always true. -- Best Regards Masahiro Yamada