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From: Olof Johansson <olof@lixom.net>
Date: Tue, 27 Jun 2017 14:16:46 -0700
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To: Linus Torvalds <torvalds@linux-foundation.org>
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Cc: Christoph Hellwig <hch@infradead.org>,
	Cristina Moraru <cristina.moraru09@gmail.com>,
	ksummit <ksummit-discuss@lists.linuxfoundation.org>,
	Michal Hocko <mhocko@kernel.org>
Subject: Re: [Ksummit-discuss] [TECH TOPIC] is Kconfig a bit hard sometimes?
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On Tue, Jun 27, 2017 at 12:27 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
> On Tue, Jun 27, 2017 at 11:44 AM, Luis R. Rodriguez <mcgrof@kernel.org> wrote:
>>
>> Such things exist now:
>>
>> make kvmconfig
>> make xenconfig
>
> Not really. Not for normal users. Those are literally only for the
> special cases that are *not* normal.
>
>> So you mean a menu of the defconfigs ?
>
> No. The defconfigs are useless. They are fundamentally broken, excatly
> because there is never one config that can work.
>
> They do need to be of the "kvmconfig" type, but for sane subconfirurations.
>
> So I'd look for something like
>
>     make modernpcconfig # enable minimal modern PC workstation stuff
>     make f25config  # enable minimal stuff required for F25
>     make amdconfig # enable the core modern AMD stuff
>
> or something like that.

It sounds to me like you want to turn it from option/driver selection
to feature selection, where features could be stuff like:
 * Basic config for modern PC
  - Intel-based
  - AMD-based
 * DBasic configs for distros
  - F25
  - Debian Jessie
  - ...
 * Virtualization
  - Platform support
    + Intel (default platform support && basic-config-for-intel)
    + AMD
  - Paravirt support
    + Drivers for paravirt platform [...]


Is that a correct interpretation of what you have in mind?


So, a meta config layer if seen in the context of our current config system.

If we were to do this incrementally with current Kconfig on the
backend, I think most of the above could be done as one config action,
that in turn would select a set of kconfig snippets on the backend,
concatenate them all and give you the config to build with.



-Olof