Re: [PATCH 00/22] gpio: rework locking and object life-time control

[Linus Walleij]

On Tue, Jan 30, 2024 at 1:48 PM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:

> We do NOT serialize all API callbacks. This means that provider callbacks
> may be called simultaneously and GPIO drivers need to provide their own
> locking if needed. This is on purpose. First: we only support exclusive
> GPIO usage[1] so there's no risk of two drivers getting in each other's
> way over the same GPIO. Second: with this series, we ensure enough
> consistency to limit the chance of drivers or user-space users crashing
> the kernel. With additional improvements in handling the flags field in
> GPIO descriptors there's very little to gain, while bitbanging drivers
> may care about the increased performance of going lockless.

OK I read this before but didn't understand it, now I understand it.

The series:
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

I think you should merge it all soon so we get some time to shake
it out in linux-next, hopefully any remaining bugs and cleanups
can be done in-tree.

Excellent work, by the way.

Yours,
Linus Walleij