[Ksummit-discuss] UAPI headers and inline function policy

[David Howells]

I noticed that include/uapi/linux/cec.h and cec-funcs.h export a bunch of
inline functions to userspace.  I think that the following should possibly be
prohibited in kernel UAPI headers:

 (1) Inline functions and function declarations.

 (2) Anonymous embedded structs and unions.

 (3) Conditionals, other than re-inclusion guards and C++ guards.  Definitely
     no dependencies on CONFIG_* or __ARCH_* or __KERNEL__.  Ideally, we
     should be able to copy the headers as-are to /usr/include/ without the
     need to run them through a filter.

 (4) The extern keyword - except when used in a C++ guard.

Now, we already have some violations of these that we probably can't get rid
of, but anything added in the last merge window we probably can deal with.

Thoughts?

David