Re: [PATCH Resend] cpufreq: Set cpufreq_cpu_data to NULL before putting kobject

ethan zhao
2015-02-02T04:16:58Z

On 2015/2/2 12:09, Viresh Kumar wrote:
> On 2 February 2015 at 09:36, ethan zhao <ethan.zhao@oracle.com> wrote:
>> Is that an idea it supposed to be or fact ?
>>
>> if (!cpufreq_suspended)
>> cpufreq_policy_free(policy);
>>
>> static void cpufreq_policy_free(struct cpufreq_policy *policy)
>> {
>> free_cpumask_var(policy->related_cpus);
>> free_cpumask_var(policy->cpus);
>> kfree(policy);
>> }
>>
>> It seems
>> you just think about it ideally in mind.
We am talking about the policy allocation and de-allocation. right ?
I showed you the cpufreq_policy_free(policy) doesn't check kobject
refcount as above.

Hmmm, you are still sleeping in the kobject, wake up and don't mix
water anymore.

Thanks,
Ethan

> if (!cpufreq_suspended)
> cpufreq_policy_put_kobj(policy);
>
> static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy)
> {
> ...
>
> kobject_put(kobj);
>
> /*
> * We need to make sure that the underlying kobj is
> * actually not referenced anymore by anybody before we
> * proceed with unloading.
> */
> pr_debug("waiting for dropping of refcount\n");
> wait_for_completion(cmp);
> }