Re: [PATCH] clk: Correct handling of NULL clk in __clk_{get, put}

Lothar Waßmann
2014-01-07T13:00:33Z

Hi,

Sylwester Nawrocki wrote:
> Ensure clk->kref is dereferenced only when clk is not NULL.
>
> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
> ---
> Hi Sachin,
>
> please try if this patch fixes the exyno5420 boot crash.
>
> Thanks,
> Sylwester
>
> drivers/clk/clk.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index e3e0327..a1fe86f 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -2179,24 +2179,25 @@ EXPORT_SYMBOL_GPL(devm_clk_unregister);
> */
> int __clk_get(struct clk *clk)
> {
> - if (clk && !try_module_get(clk->owner))
> - return 0;
> + if (clk) {
> + if (!try_module_get(clk->owner))
> + return 0;
>
This change is unnecessary! The part after the && is only evaluated
when clk is not NULL.

Lothar Waßmann
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