Re: [PATCH v2] mctp: serial: replace memset with zero-initialization

[Manish Baing]

Hi David,

I understand that this might just be unnecessary churn for the
networking subsystem, and I am perfectly fine dropping the patch if
that is the case.

However, for my own learning, I would love to get your perspective on
this. I was carrying over a pattern from recent cleanups in the IIO
subsystem [1],
as empty brace initialization was noted as the preferred approach in
those discussions (including by Kees Cook [2]).

Is the reasoning behind that recommendation just not applicable to
netdev,or is the policy here strictly against code churn unless it
fixes a tangible bug?

Thanks for the guidance.

[1]: https://lore.kernel.org/all/20250611-iio-zero-init-stack-with-instead-of-memset-v1-0-ebb2d0a24302@xxxxxxxxxxxx/
[2]: https://lore.kernel.org/linux-iio/202505090942.48EBF01B@keescook/

Regards,
Manish


On Sun, May 31, 2026 at 2:42 PM David Laight
<david.laight.linux@xxxxxxxxx> wrote:
>
> On Sat, 30 May 2026 22:46:46 +0000
> Manish Baing <manishbaing2789@xxxxxxxxx> wrote:
>
> > Use empty brace initialization (= {}) instead of explicit memset()
> > to zero-initialize stack memory to simplify the code.
> >
> > No functional change.
>
> Isn't it also entirely pointless?
>
> -- David
>
> >
> > Signed-off-by: Manish Baing <manishbaing2789@xxxxxxxxx>
> > ---
> > Changes in v2:
> > - Fixed a compilation error caused by a duplicate variable declaration caught
> >   by the kernel test robot.
> >
> >  drivers/net/mctp/mctp-serial.c | 3 +--
> >  1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/mctp/mctp-serial.c b/drivers/net/mctp/mctp-serial.c
> > index 26c9a33fd636..df721ca4e07b 100644
> > --- a/drivers/net/mctp/mctp-serial.c
> > +++ b/drivers/net/mctp/mctp-serial.c
> > @@ -536,13 +536,12 @@ struct test_chunk_tx {
> >
> >  static void test_next_chunk_len(struct kunit *test)
> >  {
> > -     struct mctp_serial devx;
> > +     struct mctp_serial devx = { };
> >       struct mctp_serial *dev = &devx;
> >       int next;
> >
> >       const struct test_chunk_tx *params = test->param_value;
> >
> > -     memset(dev, 0x0, sizeof(*dev));
> >       memcpy(dev->txbuf, params->input, params->input_len);
> >       dev->txlen = params->input_len;
> >
>