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Date:   Wed, 8 Jun 2022 02:22:10 +0200
From:   Max Staudt <max@enpas.org>
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Vincent MAILHOL <mailhol.vincent@wanadoo.fr>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Marc Kleine-Budde <mkl@pengutronix.de>,
        linux-can@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Oliver Hartkopp <socketcan@hartkopp.net>,
        netdev <netdev@vger.kernel.org>
Subject: Re: [PATCH v5 4/7] can: Kconfig: add CONFIG_CAN_RX_OFFLOAD
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On Tue, 7 Jun 2022 17:14:55 -0700
Jakub Kicinski <kuba@kernel.org> wrote:

> We have a ton of "magical" / hidden Kconfigs in networking, take a
> look at net/Kconfig. Quick grep, likely not very accurate but FWIW:

Fair enough. Thinking about it, I've grepped my distro's kernel config
for features more than just a handful of times...


> > How about making RX_OFFLOAD a separate .ko file, so we don't have
> > various possible versions of can_dev.ko?
> > 
> > @Vincent, I think you suggested that some time ago, IIRC?
> > 
> > (I know, I was against a ton of little modules, but I'm changing my
> > ways here now since it seems to help...)  
> 
> A separate module wouldn't help with my objections, I don't think.

In a system where the CAN stack is compiled as modules (i.e. a regular
desktop distribution), the feature's presence/absence would be easily
visible via the .ko file's presence/absence.

Then again, I have to agree, distributing a system where RX_OFFLOAD is
present, but no drivers using it whatsoever, seems... strange.

I guess I got lost in my thinking there, with my out of tree
development and all. Sorry for the noise.


Max