Re: [PATCH] regulator: bd718x7: Use kcalloc() instead of kzalloc()

[Qianfeng Rong]

在 2025/8/18 13:30, Matti Vaittinen 写道:
> On 17/08/2025 17:23, Qianfeng Rong wrote:
> > Replace calls of 'devm_kzalloc(dev, count * sizeof([type]), flags)'
> > with 'devm_kcalloc(dev, count, sizeof([type]), flags)' in
> > setup_feedback_loop() for safer memory allocation with built-in
> > overflow protection.
> >
> > Signed-off-by: Qianfeng Rong <rongqianfeng@xxxxxxxx>
> > ---
> >   drivers/regulator/bd718x7-regulator.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/regulator/bd718x7-regulator.c 
> > b/drivers/regulator/bd718x7-regulator.c
> > index e803cc59d68a..022d98f3c32a 100644
> > --- a/drivers/regulator/bd718x7-regulator.c
> > +++ b/drivers/regulator/bd718x7-regulator.c
> > @@ -1598,7 +1598,7 @@ static int setup_feedback_loop(struct device 
> > *dev, struct device_node *np,
> >           if (desc->n_linear_ranges && desc->linear_ranges) {
> >               struct linear_range *new;
> >   -            new = devm_kzalloc(dev, desc->n_linear_ranges *
> > +            new = devm_kcalloc(dev, desc->n_linear_ranges,
> >                          sizeof(struct linear_range),
> >                          GFP_KERNEL);
> >               if (!new)
>
> Thanks Qianfeng.
>
> I don't think this is particularly hazardous, because the 
> n_linear_ranges is known to be small. (It's populated in this same 
> file, with a size of pre-defined array). Still, this seems like a 
> valid change to me. I know some would say we should use sizeof(*new), 
> but I kind of like the sizeof(struct linear_range).


Thanks for taking the time to explain!

I also prefer sizeof(struct linear_range) to sizeof(*new) because it is 
more readable.  :)

> Reviewed-by: Matti Vaittinen <mazziesaccount@xxxxxxxxx>
>
> Yours,
>     -- Matti
Best regards,
Qianfeng