Re: [PATCH 4/5] regulator: of: add missing of_node_put

Krzysztof Kozlowski
2015-10-12T12:58:28Z

W dniu 12.10.2015 o 21:44, Julia Lawall pisze:
>
>
> On Mon, 12 Oct 2015, Krzysztof Kozlowski wrote:
>
>> 2015-10-10 21:30 GMT+09:00 Julia Lawall <Julia.Lawall@lip6.fr>:
>>>
>>> for_each_child_of_node performs an of_node_get on each iteration, so
>>> a break out of the loop requires an of_node_put.
>>>
>>> The semantic patch that fixes this problem is as follows
>>> (http://coccinelle.lip6.fr):
>>>
>>> // <smpl>
>>> @@
>>> expression root,e;
>>> local idexpression child;
>>> @@
>>>
>>> for_each_child_of_node(root, child) {
>>> ... when != of_node_put(child)
>>> when != e = child
>>> (
>>> return child;
>>> |
>>> + of_node_put(child);
>>> ? return ...;
>>> )
>>> ...
>>> }
>>> // </smpl>
>>>
>>> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
>>>
>>> ---
>>> drivers/regulator/of_regulator.c | 1 +
>>> 1 file changed, 1 insertion(+)
>>>
>>> diff --git a/drivers/regulator/of_regulator.c b/drivers/regulator/of_regulator.c
>>> index 499e437..f9d77b4 100644
>>> --- a/drivers/regulator/of_regulator.c
>>> +++ b/drivers/regulator/of_regulator.c
>>> @@ -274,6 +274,7 @@ int of_regulator_match(struct device *dev, struct device_node *node,
>>> dev_err(dev,
>>> "failed to parse DT for regulator %s\n",
>>> child->name);
>>> + of_node_put(child);
>>
>> This looks good.
>>
>>> return -EINVAL;
>>> }
>>> match->of_node = of_node_get(child);
>>
>> But what about 'break' few lines below? The reference from last
>> of_get_next_child() should be also dropped because... or we should
>> remove this of_node_get() call.
>
> Actually, the break is OK. It's on the inner for loop, not the
> for_each_child_of_node loop. The for_each_child_of_node will still
> decrement the reference count in the normal way.
>
> julia

Yes, you're right. The patch looks good:
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

Best regards,
Krzysztof

>> How about fixing also usage of for_each_available_child_of_node() in
>> regulator_of_get_init_data()?
>>
>> Best regards,
>> Krzysztof
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