Subject: Re: [PATCH 1/3] net: dsa: Use devm_ prefixed allocations

From: Felix Fietkau <[email-masked]>
Date: Sat, 3 Oct 2015 14:39:18 +0200

On 2015-10-02 15:30, Neil Armstrong wrote:
> On 10/02/2015 03:29 PM, Sergei Shtylyov wrote:
>> On 10/2/2015 1:48 PM, Neil Armstrong wrote:
>> 
>>> To simplify and prevent memory leakage when unbinding, use
>>> the devm_ memory allocation calls.
>>>
>>> Tested-by: Andrew Lunn <[email-masked]>
>>> Tested-by: Florian Fainelli <[email-masked]>
>>> Signed-off-by: Neil Armstrong <[email-masked]>
>>> ---
>>>   net/dsa/dsa.c | 6 +++---
>>>   1 file changed, 3 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
>>> index c59fa5d..98f94c2 100644
>>> --- a/net/dsa/dsa.c
>>> +++ b/net/dsa/dsa.c
>>> @@ -305,7 +305,7 @@ static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
>>>       if (ret < 0)
>>>           goto out;
>>>
>>> -    ds->slave_mii_bus = mdiobus_alloc();
>>> +    ds->slave_mii_bus = devm_mdiobus_alloc(parent);
>>>       if (ds->slave_mii_bus == NULL) {
>>>           ret = -ENOMEM;
>>>           goto out;
>>> @@ -400,7 +400,7 @@ dsa_switch_setup(struct dsa_switch_tree *dst, int index,
>>>       /*
>>>        * Allocate and initialise switch state.
>>>        */
>>> -    ds = kzalloc(sizeof(*ds) + drv->priv_size, GFP_KERNEL);
>>> +    ds = devm_kzalloc(parent, sizeof(*ds) + drv->priv_size, GFP_KERNEL);
>>>       if (ds == NULL)
>>>           return ERR_PTR(-ENOMEM);
>>>
>>> @@ -883,7 +883,7 @@ static int dsa_probe(struct platform_device *pdev)
>>>           goto out;
>>>       }
>>>
>>> -    dst = kzalloc(sizeof(*dst), GFP_KERNEL);
>>> +    dst = devm_kzalloc(&pdev->dev, sizeof(*dst), GFP_KERNEL);
>>>       if (dst == NULL) {
>>>           dev_put(dev);
>>>           ret = -ENOMEM;
>>>
>> 
>>    Shouldn't you remove the correspoding kfree(), etc. calls?
>> 
>> MBR, Sergei
>> 
> The corresponding kfree() calls were all missing.
Not in the error handling path. mdiobus_alloc has a corresponding
mdiobus_free in the same function.
The ds kzalloc in dsa_switch_setup has a kfree in dsa_switch_setup_one.

- Felix