Re: [PATCH 07/16] clk: qcom: clk-krait: add hw_parent check for div2_round_rate

[Stephen Boyd]

Quoting Ansuel Smith (2022-03-13 12:04:10)
> Check if hw_parent is present before calculating the round_rate to
> prevent kernel panic.
> 
> Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
> ---
>  drivers/clk/qcom/clk-krait.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/qcom/clk-krait.c b/drivers/clk/qcom/clk-krait.c
> index e447fcc3806d..d8af281eba0e 100644
> --- a/drivers/clk/qcom/clk-krait.c
> +++ b/drivers/clk/qcom/clk-krait.c
> @@ -80,7 +80,12 @@ EXPORT_SYMBOL_GPL(krait_mux_clk_ops);
>  static long krait_div2_round_rate(struct clk_hw *hw, unsigned long rate,
>                                   unsigned long *parent_rate)
>  {
> -       *parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw), rate * 2);
> +       struct clk_hw *hw_parent = clk_hw_get_parent(hw);
> +
> +       if (!hw_parent)
> +               return -1;

Use -EINVAL or some proper error code, not just -1

> +
> +       *parent_rate = clk_hw_round_rate(hw_parent, rate * 2);
>         return DIV_ROUND_UP(*parent_rate, 2);
>  }
>  
> -- 
> 2.34.1
>