Re: Subtle MM bug

[David Weinehall]

On Wed, Jan 10, 2001 at 07:36:43PM +0000, Alan Cox wrote:
> > 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 ;))

Are there any other (not yet supported) platforms with similar (or other
unrelated, but hard to support because of the current architecture of
the kernel) problems?

(No, I have no secret trumps up my sleeve, I'm just curious.)

/David
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