diff mbox series

Fixes: 227942809b52 ("cpufreq: powernv: Restore cpu frequency to policy->cur on unthrottling")

Message ID 20200306110549.25517-1-psampat@linux.ibm.com (mailing list archive)
State Superseded, archived
Headers show
Series Fixes: 227942809b52 ("cpufreq: powernv: Restore cpu frequency to policy->cur on unthrottling") | expand

Commit Message

Pratik R. Sampat March 6, 2020, 11:05 a.m. UTC
The patch avoids allocating cpufreq_policy on stack hence fixing frame
size overflow in 'powernv_cpufreq_work_fn'

Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com>
---
 drivers/cpufreq/powernv-cpufreq.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

Comments

Daniel Axtens March 16, 2020, 1:05 p.m. UTC | #1
Hi Pratik,

Please could you resend this with a more meaningful subject line and
move the Fixes: line to immediately above your signed-off-by?

Thanks!

Regards,
Daniel

> The patch avoids allocating cpufreq_policy on stack hence fixing frame
> size overflow in 'powernv_cpufreq_work_fn'
>
> Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com>
> ---
>  drivers/cpufreq/powernv-cpufreq.c | 13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
> index 56f4bc0d209e..20ee0661555a 100644
> --- a/drivers/cpufreq/powernv-cpufreq.c
> +++ b/drivers/cpufreq/powernv-cpufreq.c
> @@ -902,6 +902,7 @@ static struct notifier_block powernv_cpufreq_reboot_nb = {
>  void powernv_cpufreq_work_fn(struct work_struct *work)
>  {
>  	struct chip *chip = container_of(work, struct chip, throttle);
> +	struct cpufreq_policy *policy;
>  	unsigned int cpu;
>  	cpumask_t mask;
>  
> @@ -916,12 +917,14 @@ void powernv_cpufreq_work_fn(struct work_struct *work)
>  	chip->restore = false;
>  	for_each_cpu(cpu, &mask) {
>  		int index;
> -		struct cpufreq_policy policy;
>  
> -		cpufreq_get_policy(&policy, cpu);
> -		index = cpufreq_table_find_index_c(&policy, policy.cur);
> -		powernv_cpufreq_target_index(&policy, index);
> -		cpumask_andnot(&mask, &mask, policy.cpus);
> +		policy = cpufreq_cpu_get(cpu);
> +		if (!policy)
> +			continue;
> +		index = cpufreq_table_find_index_c(policy, policy->cur);
> +		powernv_cpufreq_target_index(policy, index);
> +		cpumask_andnot(&mask, &mask, policy->cpus);
> +		cpufreq_cpu_put(policy);
>  	}
>  out:
>  	put_online_cpus();
> -- 
> 2.17.1
Pratik R. Sampat March 16, 2020, 1:54 p.m. UTC | #2
Hi Daniel,

Sure thing I'll re-send them. Rookie mistake, my bad.
Thanks for pointing it out!

Regards,
Pratik

On 16/03/20 6:35 pm, Daniel Axtens wrote:
> Hi Pratik,
>
> Please could you resend this with a more meaningful subject line and
> move the Fixes: line to immediately above your signed-off-by?
>
> Thanks!
>
> Regards,
> Daniel
>
>> The patch avoids allocating cpufreq_policy on stack hence fixing frame
>> size overflow in 'powernv_cpufreq_work_fn'
>>
>> Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com>
>> ---
>>   drivers/cpufreq/powernv-cpufreq.c | 13 ++++++++-----
>>   1 file changed, 8 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
>> index 56f4bc0d209e..20ee0661555a 100644
>> --- a/drivers/cpufreq/powernv-cpufreq.c
>> +++ b/drivers/cpufreq/powernv-cpufreq.c
>> @@ -902,6 +902,7 @@ static struct notifier_block powernv_cpufreq_reboot_nb = {
>>   void powernv_cpufreq_work_fn(struct work_struct *work)
>>   {
>>   	struct chip *chip = container_of(work, struct chip, throttle);
>> +	struct cpufreq_policy *policy;
>>   	unsigned int cpu;
>>   	cpumask_t mask;
>>   
>> @@ -916,12 +917,14 @@ void powernv_cpufreq_work_fn(struct work_struct *work)
>>   	chip->restore = false;
>>   	for_each_cpu(cpu, &mask) {
>>   		int index;
>> -		struct cpufreq_policy policy;
>>   
>> -		cpufreq_get_policy(&policy, cpu);
>> -		index = cpufreq_table_find_index_c(&policy, policy.cur);
>> -		powernv_cpufreq_target_index(&policy, index);
>> -		cpumask_andnot(&mask, &mask, policy.cpus);
>> +		policy = cpufreq_cpu_get(cpu);
>> +		if (!policy)
>> +			continue;
>> +		index = cpufreq_table_find_index_c(policy, policy->cur);
>> +		powernv_cpufreq_target_index(policy, index);
>> +		cpumask_andnot(&mask, &mask, policy->cpus);
>> +		cpufreq_cpu_put(policy);
>>   	}
>>   out:
>>   	put_online_cpus();
>> -- 
>> 2.17.1
diff mbox series

Patch

diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 56f4bc0d209e..20ee0661555a 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -902,6 +902,7 @@  static struct notifier_block powernv_cpufreq_reboot_nb = {
 void powernv_cpufreq_work_fn(struct work_struct *work)
 {
 	struct chip *chip = container_of(work, struct chip, throttle);
+	struct cpufreq_policy *policy;
 	unsigned int cpu;
 	cpumask_t mask;
 
@@ -916,12 +917,14 @@  void powernv_cpufreq_work_fn(struct work_struct *work)
 	chip->restore = false;
 	for_each_cpu(cpu, &mask) {
 		int index;
-		struct cpufreq_policy policy;
 
-		cpufreq_get_policy(&policy, cpu);
-		index = cpufreq_table_find_index_c(&policy, policy.cur);
-		powernv_cpufreq_target_index(&policy, index);
-		cpumask_andnot(&mask, &mask, policy.cpus);
+		policy = cpufreq_cpu_get(cpu);
+		if (!policy)
+			continue;
+		index = cpufreq_table_find_index_c(policy, policy->cur);
+		powernv_cpufreq_target_index(policy, index);
+		cpumask_andnot(&mask, &mask, policy->cpus);
+		cpufreq_cpu_put(policy);
 	}
 out:
 	put_online_cpus();