Re: [PATCH 1/2] Revert "include/uapi/drm/amdgpu_drm.h: use __u32 and __u64 from <linux/types.h>"

[Mikko Rapeli]

Cc'ing lkml too.

On Fri, Aug 19, 2016 at 11:54:21PM +0100, Emil Velikov wrote:
> Story time:
> I was dreaming of a day were we can stop installing these headers,
> thus making deprecation a bit easier process.
> Yet after failing to convince Dave and Daniel on a number of occasions
> I've accepted that those headers _are_ here to stay. And yes they
> _are_ the UAPI, even though no applications are meant to use them but
> the libdrm 'version'.
> Thus any changes to the libdrm ones should be a mirror of the ones
> here and libdrm should _not_ differ.

Another day dream:

Wouldn't it be nice if the uapi headers from Linux kernel would pass
a simple quality check of compiling in userspace where they are meant to be
used? Stand alone. Without magic tricks and additional libraries and their
headers. Without glibc or any other libc implementation specific additions.
The uapi headers define many parts of the Linux kernel API and ABI, and thus
compiling them also without the 'official' GNU/Linux userspace libraries
like glibc or libdrm does have some uses. For example API and ABI
compatibility checks and API/ABI/system call fuzzers.

Many headers required stdint.h types but Linux kernel headers do not
define them in userspace, and then Linus has said that uapi headers
should use the linux/types.h with double underscores. Thus my patches
for fixing trivial compile errors turned into changing several stdint.h
definitions to linux/types.h.

Yes, there have been some regressions in this work but to err is human.
What is the actual problem and how can we (yes, including me) try to
solve it?

-Mikko