On 09/29/2015 07:36 AM, Matt Fleming wrote:

 
That's a pretty good summary for x86. I think specifically the reason
we map the EFI memmap entries "backwards" (entry N has higher VA than
entry N+1) is because the code was easier to write that way, but
you'll know better than me ;-)

There were two reasons:

1. The code was easier to write.
2. Windows did it that way.

Windows apparently broke and was changed due to this feature, too.

	-hpa