Re: [tip:x86/mm] x86/boot/compressed/64: Describe the logic behind the LA57 check

[Ingo Molnar]

* Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> wrote:

> > We can of course bike shed / benchmark this once my desktop refresh
> > sports this feature, but ISTR this being one of the very first things
> > Ingo mentioned when we started this whole 5L thing.
> 
> I would rather not fix the problem that may not actually exist. :)

That 5 level pagetables involve more overhead is a realy problem.

By default we should only enable 5-level paging if memory mappings exist in
the memory map that require the extended physical memory space.

Thanks,

	Ingo