[RFC v2 04/13] x86/mm: Add helper functions for MKTME memory encryption keys

[Andy Lutomirski]

> On Dec 3, 2018, at 11:39 PM, Alison Schofield <alison.schofield at intel.com> wrote:
> 
> Define a global mapping structure to manage the mapping of userspace
> Keys to hardware KeyIDs in MKTME (Multi-Key Total Memory Encryption).
> Implement helper functions that access this mapping structure.
> 

Why is a key “void *”?  Who owns the memory?  Can a real type be used?