Re: [PATCH 22/99] fbdev/fsl-diu-fb: Duplicate video-mode option string

From: Timur Tabi
Date: Wed Mar 08 2023 - 11:28:27 EST


On Tue, Mar 7, 2023 at 2:28 AM Thomas Zimmermann <tzimmermann@xxxxxxx> wrote:
> > So after module_init is finished, mode_option_buf[] no longer exists?
>
> Does the __init attribute on a function affect the static variables in
> that function?

That is an excellent question.

https://stackoverflow.com/questions/64558614/what-happens-to-local-static-identifiers-in-init-function

I don't think the compiler is naturally aware of whatever section a
variable or function is placed in, so it can't really know that
mode_option_buf[] is suppose to have a limited lifetime.

Either way, the code seems wrong. If mode_option_buf[] is marked as
__initdata, then it will disappear before the probe() function is
called.

If mode_option_buf[] remains resident, then we are wasting 256 bytes.