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From: Linus Walleij <linus.walleij@linaro.org>
Date: Thu, 6 Sep 2018 12:04:53 +0200
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To: Kees Cook <keescook@chromium.org>
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Subject: Re: [Ksummit-discuss] [MAINTAINERS SUMMIT] API
	replacement/deprecation
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On Thu, Sep 6, 2018 at 12:57 AM Kees Cook <keescook@chromium.org> wrote:

> Slow:
> Introduce new API in release N. Trickle patches in over N+M releases,
> removing old API when no more uses are present.
> Pros:
> - patches are written and handed to maintainers at a regular rate
> - testing happens normally
> Cons:
> - new users of the old API continue to enter the kernel, causing an
> endless cycle of needing more work
> - API may never get deprecated
> Example: strscpy(), VLA removal

GPIO descriptors trying to remove the global GPIO numbers, in
turn inspired by the IRQ number removal trying to remove
global IRQ numbers.

I am moving forward with the GPIO work, sometimes I even get
help.

As the process involves building manu esoteric architectures
I have been most helped by Arnd deleting cruft archs such as
blackfin and the 0day kbuild hitting me on the head for all
stupid mistakes I make, this has added some momentum to
the trickliness so it is more like a brook these days. It's still
not quick.

Yours,
Linus Walleij