As idr_alloc() can return negative numbers,
it should be better to check the return value and
deal with the exception.

Fixes: 6adba21eb434 ("soc: qcom: Add APR bus driver")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/soc/qcom/apr.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c
index b4046f393575..1b73ce9b4f9a 100644
--- a/drivers/soc/qcom/apr.c
+++ b/drivers/soc/qcom/apr.c
@@ -454,8 +454,12 @@ static int apr_add_device(struct device *dev, struct device_node *np,
 	adev->dev.driver = NULL;
 
 	spin_lock(&apr->svcs_lock);
-	idr_alloc(&apr->svcs_idr, svc, svc_id, svc_id + 1, GFP_ATOMIC);
+	ret = idr_alloc(&apr->svcs_idr, svc, svc_id, svc_id + 1, GFP_ATOMIC);
 	spin_unlock(&apr->svcs_lock);
+	if (ret < 0) {
+		kfree(adev);
+		return ret;
+	}
 
 	of_property_read_string_index(np, "qcom,protection-domain",
 				      1, &adev->service_path);
-- 
2.25.1

On 9/12/2022 7:30 PM, Jiasheng Jiang wrote:
> As idr_alloc() can return negative numbers,
> it should be better to check the return value and
> deal with the exception.
> 
> Fixes: 6adba21eb434 ("soc: qcom: Add APR bus driver")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>   drivers/soc/qcom/apr.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c
> index b4046f393575..1b73ce9b4f9a 100644
> --- a/drivers/soc/qcom/apr.c
> +++ b/drivers/soc/qcom/apr.c
> @@ -454,8 +454,12 @@ static int apr_add_device(struct device *dev, struct device_node *np,
>   	adev->dev.driver = NULL;
>   
>   	spin_lock(&apr->svcs_lock);
> -	idr_alloc(&apr->svcs_idr, svc, svc_id, svc_id + 1, GFP_ATOMIC);
> +	ret = idr_alloc(&apr->svcs_idr, svc, svc_id, svc_id + 1, GFP_ATOMIC);
>   	spin_unlock(&apr->svcs_lock);
> +	if (ret < 0) {
> +		kfree(adev);
> +		return ret;
> +	}

for consistency suggest you follow the same error logic as the 
device_register() failure just below, call dev_err() and put_device()

On 9/12/2022 8:51 PM, Jeff Johnson wrote:
> On 9/12/2022 7:30 PM, Jiasheng Jiang wrote:
>> As idr_alloc() can return negative numbers,
>> it should be better to check the return value and
>> deal with the exception.
>>
>> Fixes: 6adba21eb434 ("soc: qcom: Add APR bus driver")
>> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
>> ---
>>   drivers/soc/qcom/apr.c | 6 +++++-
>>   1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c
>> index b4046f393575..1b73ce9b4f9a 100644
>> --- a/drivers/soc/qcom/apr.c
>> +++ b/drivers/soc/qcom/apr.c
>> @@ -454,8 +454,12 @@ static int apr_add_device(struct device *dev, 
>> struct device_node *np,
>>       adev->dev.driver = NULL;
>>       spin_lock(&apr->svcs_lock);
>> -    idr_alloc(&apr->svcs_idr, svc, svc_id, svc_id + 1, GFP_ATOMIC);
>> +    ret = idr_alloc(&apr->svcs_idr, svc, svc_id, svc_id + 1, 
>> GFP_ATOMIC);
>>       spin_unlock(&apr->svcs_lock);
>> +    if (ret < 0) {
>> +        kfree(adev);
>> +        return ret;
>> +    }
> 
> for consistency suggest you follow the same error logic as the 
> device_register() failure just below, call dev_err() and put_device()
> 

in addition the of_property_read_string_index() that follows could also 
use error checking