Re: [PATCH 00 of 36] x86/paravirt: groundwork for 64-bit Xen support

Andi Kleen
2008-06-25T12:40:32Z

Jeremy Fitzhardinge <jeremy@goop.org> writes:
>
> This moves __PAGE_OFFSET up by 16 GDT slots, from 0xffff810000000000

GDT? PDP?

> to 0xffff880000000000. I have no general justification for this: th

This will significantly decrease the maximum amount of physical
memory supported by Linux longer term.

> "x86_64: PSE no longer a hard requirement."
>
> Because booting under Xen doesn't set PSE, it's no longer a hard
> requirement for the kernel. PSE will be used whereever possible.

Both sound like cases of "let's hack Linux to work around Xen
problems"

-Andi