Re: [MAINTAINER SUMMIT] Enforcing API deprecation

Jiri Kosina
2025-08-26T20:28:17Z

On Tue, 26 Aug 2025, Linus Torvalds wrote:

> > I would like to propose a discussion on how to enforce API deprecation
> > in a way that supports efforts to reduce technical debt, without being
> > hampered by developers and maintainers who mean no harm but simply
> > don’t know any better.
>
> Here's the only thing that works: if you change the API, you have to
> fix up all existing users.
>
> If you are not willing to fix up all existing users, and you introduce
> a parallel API, then you are the one that maintains both the old and
> the new API forever.

I don't disagree, I just feel that it's important to note that it's pretty
much impossible to do a proper functional testing of many such
conversions.
Especially when drivers are involved on the consuming side. Even more so
if obscure ones (which is quite often the case in driver space).

But yes, if there are people who do care about such drivers, they will
speak up once they get hit by the breakage, so it's not a huge problem
either.

--
Jiri Kosina
SUSE Labs