kref doc: Why kref kernel doc omits kref_put when kthread_run fail

[YuLicheng]

The document is /Documentation/kerf.txt, and I'm referring to v3.12:
https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/tree/Documentation/kref.txt?id=v3.12

Part of the first example in the document is attached below.
In my_data_handler(), kref_init() already put 1 to refcount, and kref_get()
next made the refcount 2. But if kthread_run() fails, only one kref_put() 
will
take place (right after the out tag), it renders the refcount to be 1 at 
last,
and the data will never be freed.

int my_data_handler(void)
{
       int rv = 0;
       struct my_data *data;
       struct task_struct *task;
       data = kmalloc(sizeof(*data), GFP_KERNEL);
       if (!data)
               return -ENOMEM;
       kref_init(&data->refcount);

       kref_get(&data->refcount);
       task = kthread_run(more_data_handling, data, "more_data_handling");
       if (task == ERR_PTR(-ENOMEM)) {
               rv = -ENOMEM;
               goto out;
       }

       .
       . do stuff with data here
       .
out:
       kref_put(&data->refcount, data_release);
       return rv;
}

I also noticed that there once was a kref_put() before "goto out" in the doc
before some point of 2009, but it was removed by a patch that claimed that 
this
kref_put() was redudent.
The patch commit is:
https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/Documentation/kref.txt?id=8f1ecc9fbc5b223e4f5d5bb8bcd6f5672c4bc4b6

Is this a bug or maybe I missed something?


       Licheng 

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