Re: [PATCH] gpiolib: use __counted_by() for GPIO descriptors

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>]

On Tue, Dec 19, 2023 at 01:57:06PM +0100, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> 
> Pull the array of GPIO descriptors into struct gpio_device as a flexible
> array and use __counted_by() to control its size.

How big is the struct gpio_device? Unifying like this might provoke subtle
errors on very fragmented memory, where k*alloc() might not find enough free
space. Note, k*alloc() guarantees finding only memory for a single page.
With PAGE_SIZE = 4k, this might be an issue.

I would suggest, if nothing prevents us from switching, to use kvmalloc().

-- 
With Best Regards,
Andy Shevchenko