Re: [PATCH] gpio: msc313: remove kcalloc

[Rosen Penev]

On Sun, Mar 8, 2026 at 5:06 PM Linus Walleij <linusw@xxxxxxxxxx> wrote:
>
> On Sun, Mar 8, 2026 at 3:15 AM Rosen Penev <rosenp@xxxxxxxxx> wrote:
>
> > Use a flexible array member to combine kzalloc and kcalloc.
> >
> > Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
> (...)
> >  struct msc313_gpio {
> >         void __iomem *base;
> >         const struct msc313_gpio_data *gpio_data;
>
> Do you wanna add:
>
> const unsigned int saved_size;
So in the code there's

for (i = 0; i < gpio->gpio_data->num; i++)

which is equivalent to match->num.

__counted_by doesn't support pointers AFAIK.
>
> > -       u8 *saved;
> > +       u8 saved[];
>
> u8 saved[] __counted_by(saved_size);
>
> >  static int msc313_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
> > @@ -631,16 +631,12 @@ static int msc313_gpio_probe(struct platform_device *pdev)
> >         if (!parent_domain)
> >                 return -ENODEV;
> >
> > -       gpio = devm_kzalloc(dev, sizeof(*gpio), GFP_KERNEL);
> > +       gpio = devm_kzalloc(dev, struct_size(gpio, saved, match_data->num), GFP_KERNEL);
> >         if (!gpio)
> >                 return -ENOMEM;
>
> gpio->saved_size = match_data->num;
>
> I know it takes some bytes more but it feels way safer.
>
> Yours,
> Linus Walleij