Re: Subtle MM bug

[Alan Cox]

> I looked at it a year or two ago myself, and came to the conclusion that I
> don't want to blow up our page table size by a factor of three or more, so
> I'm not personally interested any more. Maybe somebody else comes up with
> a better way to do it, or with a really compelling reason to.

There is only one reason I know for reverse page tables. That is ARM2/ARM3 
support - which is still not fully merged because of this issue

The MMU on these systems is a CAM, and the mmu table is thus backwards to
convention. (It also means you can notionally map two physical addresses to
one virtual but thats undefined in the implementation ;))