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Subject: Re: [RFC PATCH 0/5] Add CONFIG symbol as module attribute
To: Christoph Hellwig <hch@lst.de>,
        "Luis R. Rodriguez" <mcgrof@kernel.org>
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From: Michal Marek <mmarek@suse.com>
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Date: Thu, 25 Aug 2016 10:41:25 +0200
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On 2016-08-25 09:43, Christoph Hellwig wrote:
> The idea seems useful, but I reallt don't like the 'reverse-engineering'
> approach.
> 
> If we want to this properly from the ground up we should just split out
> our CONFIG_ SYMBOLS into
> 
> MODULE_* - builds exactly one module (tristate, or maybe also as a built-in
> only one, then like a bool)
> 
> CONFIG_* - just bool, MODULE_ may depend on it, too.
> 
> The other nice thing is that we could probably fold most of the Makefiles
> into Kconfig using that methods as well, by listing the objectes required
> for a module, e.g.
> 
> module NVME_TARGET
> 	tristate "NVMe Target support"
> 	depends on BLOCK
> 	depends on CONFIGFS_FS
> 	name nvmet
> 	objects core.o configfs.o admin-cmd.o io-cmd.o fabrics-cmd.o
> 	objects discovery.o
> 
> module NVME_TARGET_LOOP
> 	tristate "NVMe loopback device support"
> 	depends on BLK_DEV_NVME
> 	depends on NVME_TARGET
> 	select NVME_FABRICS
> 	select SG_POOL
> 	name nvme-loop
> 	objects loop.o

It looks nice for the simple case, but as soon as you need something
non-standard, you will need to mix a kconfig generated and a manually
written Makefile snippet.

Michal