Re: [PATCH 2/2] cpufreq: prevent lockup on reading scaling_available_frequencies

[Viresh Kumar <viresh.kumar@linaro.org>]

On 01-10-15, 15:23, Srinivas Pandruvada wrote:
> When scaling_available_frequencies is read on an offlined cpu, then
> either lockup or junk values are displayed. This is caused by
> freed freq_table, which policy is using.
> 
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
> ---
>  drivers/cpufreq/cpufreq.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index ef5ed94..25c4c15 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -1436,8 +1436,10 @@ static void cpufreq_offline_finish(unsigned int cpu)
>  	 * since this is a core component, and is essential for the
>  	 * subsequent light-weight ->init() to succeed.
>  	 */
> -	if (cpufreq_driver->exit)
> +	if (cpufreq_driver->exit) {
>  		cpufreq_driver->exit(policy);
> +		policy->freq_table = NULL;
> +	}
>  }

freq_table was set from the ->init() callbacks and only they should
set it to NULL, isn't it?

-- 
viresh