[PATCH 01/22] clk: check hw and hw->dev before dereference it

[Simon Glass]

Hi Claudiu,

On Tue, 4 Aug 2020 at 01:19, <Claudiu.Beznea at microchip.com> wrote:
>
>
>
> On 04.08.2020 05:00, Simon Glass wrote:
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> >
> > Hi Claudiu,
> >
> > On Wed, 29 Jul 2020 at 08:51, Claudiu Beznea
> > <claudiu.beznea at microchip.com> wrote:
> >>
> >> Check hw and hw->dev before dereference it.
> >>
> >> Signed-off-by: Claudiu Beznea <claudiu.beznea at microchip.com>
> >> ---
> >>  drivers/clk/clk.c | 3 +++
> >>  1 file changed, 3 insertions(+)
> >>
> >
> > Why is this needed? It adds to code size and these situations should
> > not occur. Perhaps use assert()?
>
> In my debugging, investigating the issues that patches 03/22, 04/22, 06/22
> try to address, I reached also this function and checked these pointers. In
> the end the issue was not related to them but I though it might be useful
> to keep these in a patch. I will remove it in the next version.

IMO we should use assert() to check invariants and catch basic
programming errors. But production testing should make sure that the
software basically works.

Of course it is nice to have these checks, but they add to code size
which is always a concern. So I think we should rely on assert() to
catch the errors during development, so we are not wasting code
checking for things that we know cannot happen.

Regards,
Simon