ELF: what should be part of the userspace headers?

[Adrian Bunk]

I'm currently a bit lost trying to understand what from the following 
headers is part of the kernel <-> userspace ABI:
include/asm/elf.h
include/linux/elfcore.h
include/linux/elf-em.h
include/linux/elf-fdpic.h
include/linux/elf.h

include/linux/elf-em.h is used by include/linux/audit.h, but this usage 
doesn't seem to be part of the kernel <-> userspace interface?

And which part of the ELF headers is part of the kernel <-> userspace 
interface?

TIA
Adrian

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