Re: [PATCH 2/3] cpufreq: ppc: Fix integer overflow in expression

[Viresh Kumar]

On 17 April 2014 15:23, Geert Uytterhoeven <geert+renesas@xxxxxxxxx> wrote:
> On 32-bit, "12 * NSEC_PER_SEC" doesn't fit in "unsigned long"
> (NSEC_PER_SEC is a "long" constant), causing an integer overflow:
>
> drivers/cpufreq/ppc-corenet-cpufreq.c: In function 'corenet_cpufreq_cpu_init':
> drivers/cpufreq/ppc-corenet-cpufreq.c:211:9: warning: integer overflow in expression [-Woverflow]
>
> Force the intermediate to be 64-bit by adding an "ULL" suffix to the
> constant multiplier to fix this.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
>  drivers/cpufreq/ppc-corenet-cpufreq.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/ppc-corenet-cpufreq.c b/drivers/cpufreq/ppc-corenet-cpufreq.c
> index e78f9c806de4..53881d78a931 100644
> --- a/drivers/cpufreq/ppc-corenet-cpufreq.c
> +++ b/drivers/cpufreq/ppc-corenet-cpufreq.c
> @@ -208,7 +208,7 @@ static int corenet_cpufreq_cpu_init(struct cpufreq_policy *policy)
>                 per_cpu(cpu_data, i) = data;
>
>         policy->cpuinfo.transition_latency =
> -                               (12 * NSEC_PER_SEC) / fsl_get_sys_freq();
> +                               (12ULL * NSEC_PER_SEC) / fsl_get_sys_freq();
>         of_node_put(np);
>
>         return 0;

Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
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