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Date: Sat, 11 Sep 2021 13:31:02 +0300
From: Leon Romanovsky <leon@kernel.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Josh Triplett <josh@joshtriplett.org>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Jonathan Corbet <corbet@lwn.net>, ksummit@lists.linux.dev
Subject: Re: [MAINTAINER SUMMIT] User-space requirements for accelerator
 drivers
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In-Reply-To: <87ilz8c7ff.ffs@tglx>

On Sat, Sep 11, 2021 at 01:55:16AM +0200, Thomas Gleixner wrote:
> On Fri, Sep 10 2021 at 16:45, Josh Triplett wrote:
> 
> > On Sat, Sep 11, 2021 at 12:52:14AM +0200, Mauro Carvalho Chehab wrote:
> >> On media, enforcing userspace to always be open source would
> >> have been very bad, as it would prevent several videoconferencing 
> >> software to exist on Linux.
> >
> > I don't think we should enforce that all userspace users of an interface
> > be Open Source. I do think we should enforce that *some* userspace user
> > of an interface be Open Source before we add the interface.
> 
> The real question is whether the interface is documented in a way that
> an Open Source implementation is possible. It does not matter whether it
> exists at that point in time or not. Even if it exists there is no
> guarantee that it is feature complete.
> 
> Freely accessible documentation is really the key.

I have more radical view than you and think that documentation is far
from being enough. I would like to see any userspace API used (or to be
used) in any package which exists in Debiam/Fedora/SuSE.

Only this will give us some sort of confidence that API and device are usable
to some level. As a side note, we will be able to estimate possible API
deprecation/fix/extension based on simple search in package databases.

IMHO, github projects to show API usage are the worst possible way to
allow acceptance for new userspace API.

Thanks

> 
> Thanks,
> 
>         tglx
> 
> 
>