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SubjectRE: [PATCH v3 2/2] clk:mmp: clk-mix.c fix divide-by-zero
Quoting Nixiaoming (2019-04-24 08:34:54)
> On Wed, Apr 24, 2019 at 7:00 AM Stephen Boyd <> wrote:
> >Quoting nixiaoming (2019-03-30 06:55:42)
> >> The _get_div() function has a branch with a return value of 0
> >> Add a check on the return value of _get_div() to avoid divide-by-zero
> >>
> >
> >Are you seeing this in practice? Or just trying to avoid a div-by-zero
> >case that you've found from inspection?
> >
> This potential bug is found by code inspection.
> _get_div() is defined as a static function which is only refered twice
> in drivers/clk/mmp/clk-mix.c. In both cases the return value of _get_div()
> is used as divider without any check.
> If _get_div() never returns 0, then the branch returning 0 is dead code,
> or the return value should be check to avoid dividing by zero error.

Ok. If it's found by code inspection then I'd rather wait until someone
can confirm what the behavior should be when _get_div() returns 0. Is it
an error case that never happens or does the hardware support 0 as a
divider value meaning "bypass"? I'd like to understand that before
patching up a potential div-by-zero case and not knowing what it means.

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