[PATCH] PM / devfreq: unlock mutex and free devfreq struct in error path

[PATCH] PM / devfreq: unlock mutex and free devfreq struct in error path

[Lukasz Luba]

The devfreq->lock is held for time of setup. Release the lock in the
error path, before jumping to the end of the function.

Change the goto destination which frees the allocated memory.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
---
 drivers/devfreq/devfreq.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index b6d3e7db0b09..99b2eeedc238 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -822,7 +822,8 @@ struct devfreq *devfreq_add_device(struct device *dev,
 
 	if (devfreq->profile->timer < 0
 		|| devfreq->profile->timer >= DEVFREQ_TIMER_NUM) {
-		goto err_out;
+		mutex_unlock(&devfreq->lock);
+		goto err_dev;
 	}
 
 	if (!devfreq->profile->max_state && !devfreq->profile->freq_table) {
-- 
2.17.1

Re: [PATCH] PM / devfreq: unlock mutex and free devfreq struct in error path

[Chanwoo Choi]

Hi Lukasz,

On 3/13/21 3:45 AM, Lukasz Luba wrote:
> The devfreq->lock is held for time of setup. Release the lock in the
> error path, before jumping to the end of the function.
> 
> Change the goto destination which frees the allocated memory.
> 
> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
> ---
>  drivers/devfreq/devfreq.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index b6d3e7db0b09..99b2eeedc238 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -822,7 +822,8 @@ struct devfreq *devfreq_add_device(struct device *dev,
>  
>  	if (devfreq->profile->timer < 0
>  		|| devfreq->profile->timer >= DEVFREQ_TIMER_NUM) {
> -		goto err_out;
> +		mutex_unlock(&devfreq->lock);
> +		goto err_dev;
>  	}
>  
>  	if (!devfreq->profile->max_state && !devfreq->profile->freq_table) {
> 

Looks good to me. But, need to add the following information
and please use capital letter of the first character of patch title. Thanks.

Fixes: 4dc3bab8687f ("PM / devfreq: Add support delayed timer for polling mode")

Also, need to send it to stable lkml.

-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

Re: [PATCH] PM / devfreq: unlock mutex and free devfreq struct in error path

[Lukasz Luba]

Hi Chanwoo,

On 3/15/21 7:20 AM, Chanwoo Choi wrote:
> Hi Lukasz,
> 
> On 3/13/21 3:45 AM, Lukasz Luba wrote:
>> The devfreq->lock is held for time of setup. Release the lock in the
>> error path, before jumping to the end of the function.
>>
>> Change the goto destination which frees the allocated memory.
>>
>> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
>> ---
>>   drivers/devfreq/devfreq.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>> index b6d3e7db0b09..99b2eeedc238 100644
>> --- a/drivers/devfreq/devfreq.c
>> +++ b/drivers/devfreq/devfreq.c
>> @@ -822,7 +822,8 @@ struct devfreq *devfreq_add_device(struct device *dev,
>>   
>>   	if (devfreq->profile->timer < 0
>>   		|| devfreq->profile->timer >= DEVFREQ_TIMER_NUM) {
>> -		goto err_out;
>> +		mutex_unlock(&devfreq->lock);
>> +		goto err_dev;
>>   	}
>>   
>>   	if (!devfreq->profile->max_state && !devfreq->profile->freq_table) {
>>
> 
> Looks good to me. But, need to add the following information
> and please use capital letter of the first character of patch title. Thanks.

thanks for looking at this, sure, I'll use the capital letter.

> 
> Fixes: 4dc3bab8687f ("PM / devfreq: Add support delayed timer for polling mode")
> 
> Also, need to send it to stable lkml.
> 

I'll add the 'Fixes' tag and send v2 also into stable v5.8+:

Cc: v5.8+ <stable@vger.kernel.org> # v5.8+

Regards,
Lukasz