Re: [PATCH v2 1/2] staging: wilc1000: fix error handling in wilc_debugfs_init()

[Luis de Bethencourt]

On 25/06/16 23:16, Greg KH wrote:
> On Sat, Jun 25, 2016 at 10:43:33PM +0100, Luis de Bethencourt wrote:
>> On 25/06/16 22:36, Greg KH wrote:
>>> On Thu, Jun 23, 2016 at 01:36:17PM +0100, Luis de Bethencourt wrote:
>>>> The common format to check if a function returned an error pointer is to
>>>> use PTR_ERR(). Instead of ERR_PTR() which is used to return said errors.
>>>>
>>>> Signed-off-by: Luis de Bethencourt <luisbg@xxxxxxxxxxxxxxx>
>>>> Reviewed-by: Julian Calaby <julian.calaby@xxxxxxxxx>
>>>> ---
>>>>  drivers/staging/wilc1000/wilc_debugfs.c | 2 +-
>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/staging/wilc1000/wilc_debugfs.c b/drivers/staging/wilc1000/wilc_debugfs.c
>>>> index fcbc95d..48797dc 100644
>>>> --- a/drivers/staging/wilc1000/wilc_debugfs.c
>>>> +++ b/drivers/staging/wilc1000/wilc_debugfs.c
>>>> @@ -107,7 +107,7 @@ static int __init wilc_debugfs_init(void)
>>>>  	struct wilc_debugfs_info_t *info;
>>>>  
>>>>  	wilc_dir = debugfs_create_dir("wilc_wifi", NULL);
>>>> -	if (wilc_dir ==  ERR_PTR(-ENODEV)) {
>>>> +	if (PTR_ERR(wilc_dir) == -ENODEV) {
>>>>  		/* it's not error. the debugfs is just not being enabled. */
>>>>  		printk("ERR, kernel has built without debugfs support\n");
>>>>  		return 0;
>>>
>>> No, the best way to do this is to just ignore the return value, you
>>> don't care about it.  It can be passed back into any debugfs calls just
>>> fine.
>>>
>>> So don't check the value and all is good, debugfs was written in a way
>>> to make it _easy_ to use, no need for fancy error checking at all with
>>> it.
>>>
>>> thanks,
>>>
>>> greg k-h
>>>
>>
>> Thanks for the review Greg.
>>
>> Just to make sure. You are proposing I just drop the 3 if checks? [0]
>>
>> If that's what you mean I will send a patch as soon as you confirm :)
>>
>> Happy hacking,
>> Luis
>>
>>
>>
>> [0] Making the function look like this:
>> static int __init wilc_debugfs_init(void)
>> {
>>         int i;
>>
>>         struct dentry *debugfs_files;
>>         struct wilc_debugfs_info_t *info;
>>
>>         wilc_dir = debugfs_create_dir("wilc_wifi", NULL);
>>         for (i = 0; i < ARRAY_SIZE(debugfs_info); i++) {
>>                 info = &debugfs_info[i];
>>                 debugfs_files = debugfs_create_file(info->name,
>>                                                     info->perm,
>>                                                     wilc_dir,
>>                                                     &info->data,
>>                                                     &info->fops);
> 
> Why even assign anything to debugfs_files?
> 

Sorry Greg.

I was just confirming I understood your suggestion, and pasted that
without cleaning the code.

Thanks for review and idea!
Luis