On 10/30/2013 01:03 AM, Linus Torvalds wrote:
> On Tue, Oct 29, 2013 at 12:27 PM, Raghavendra K T
> <raghavendra.kt@linux.vnet.ibm.com> wrote:
>>
>> Could one solution be cascading actual error
>> that is lost in fs/debugfs/inode.c:__create_file(), so that we could
>> take correct action in case of failure of debugfs_create_dir()?
>>
>> (ugly side is we increase total number of params for __create_file to
>> 6). or I hope there could be some better solution.
>
> The solution to this would be to simply return an error-pointer. See
> <linux/err.h>. That's what we do for most complex subsystems that
> return a pointer to a struct: rather than returning "NULL" as an
> error, return the actual error number encoded in the pointer itself.

Thank you Linus. Yes, this would have been ideal.

>
> But that would require every user of debugfs_create_dir() to be
> updated to check errors using IS_ERR() instead of checking against
> NULL, and there's quite a few of them.
>
> So I think just making the error be EEXIST is a simpler solution right now.
>

Agree.
I had below patch, and just before sending as formal mail I saw
Paolo's pull request which already took care of it.
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