Re: [PATCH] lib: dynamic_debug: no need to check return value of debugfs_create functions

From: Jason Baron
Date: Thu Jun 13 2019 - 12:15:04 EST




On 6/13/19 11:59 AM, Greg Kroah-Hartman wrote:
> On Thu, Jun 13, 2019 at 10:33:23AM -0400, Jason Baron wrote:
>> On 6/12/19 11:35 AM, Greg Kroah-Hartman wrote:
>>> When calling debugfs functions, there is no need to ever check the
>>> return value. The function can work or not, but the code logic should
>>> never do something different based on this.
>>>
>>> Cc: Jason Baron <jbaron@xxxxxxxxxx>
>>> Cc: linux-kernel@xxxxxxxxxxxxxxx
>>> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>>> ---
>>> lib/dynamic_debug.c | 12 +++---------
>>> 1 file changed, 3 insertions(+), 9 deletions(-)
>>>
>>> diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
>>> index 8a16c2d498e9..c60409138e13 100644
>>> --- a/lib/dynamic_debug.c
>>> +++ b/lib/dynamic_debug.c
>>> @@ -993,20 +993,14 @@ static __initdata int ddebug_init_success;
>>>
>>> static int __init dynamic_debug_init_debugfs(void)
>>> {
>>> - struct dentry *dir, *file;
>>> + struct dentry *dir;
>>>
>>> if (!ddebug_init_success)
>>> return -ENODEV;
>>>
>>> dir = debugfs_create_dir("dynamic_debug", NULL);
>>> - if (!dir)
>>> - return -ENOMEM;
>>> - file = debugfs_create_file("control", 0644, dir, NULL,
>>> - &ddebug_proc_fops);
>>> - if (!file) {
>>> - debugfs_remove(dir);
>>> - return -ENOMEM;
>>> - }
>>> + debugfs_create_file("control", 0644, dir, NULL, &ddebug_proc_fops);
>>> +
>>> return 0;
>>> }
>>>
>>>
>>
>> Looks like debugfs_create_dir() can return NULL,
>
> No it can not.
>

Ok, I looked at the wrong definition for failed_creating() :(
In that case:

Acked-by: Jason Baron <jbaron@xxxxxxxxxx>

Thanks,

-Jason