Re: [PATCH 3/3] types: use fixed width types without double-underscore prefix

From: Masahiro Yamada
Date: Wed May 16 2018 - 02:27:30 EST


2018-05-16 15:26 GMT+09:00 Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>:
> On Wed, May 16, 2018 at 10:07:50AM +0900, Masahiro Yamada wrote:
>> Hi Andrew,
>>
>> 2018-05-16 7:59 GMT+09:00 Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>:
>> > On Tue, 15 May 2018 11:22:05 +0900 Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> wrote:
>> >
>> >> This header file is not exported. It is safe to reference types
>> >> without double-underscore prefix.
>> >>
>> >
>> > It may be safe to do this, but why is it desirable?
>>
>>
>> It is shorter. That's all.
>> If it is a noise commit, please feel free to drop it.
>>
>>
>> BTW, a large amount of kernel-space code
>> uses underscore-prefixed types.
>
> Sometimes it can/should do that.

I agree that UAPI headers must do that.

If you mean "it should even for non-exported code",
I have no idea why.



>> I wonder if we could check it by checkpatch.pl or something...
>
> You do understand the difference between the two types and why/when they
> are needed, right? I don't think checkpatch.pl can determine if data is
> coming from userspace or not very easily to make this a simple perl
> script check :(


I am getting puzzled...

It sounds like you are talking about __user or __kernel.
If so, it is a matter of sparse tool
but I believe it is a different topic.


If I understand correctly,
using 'u32' is safe outside of 'include/uapi/' and
arch/$(SRCARCH)/include/uapi/

Why can't a simple script do that?

Am I missing something?



> thanks,
>
> greg k-h



--
Best Regards
Masahiro Yamada