bryce@cbmvax.commodore.com (Bryce Nesbitt) (04/08/90)
:::Questions for any MMU hacks out there:::
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1> I'm using a page table that imposes the same severe write-protection on both
Supervisor and User mode access to a certain area of memory. From time to
time the Supervisor must write a longword to this area of memory. I'm
looking for a more efficient way to subvert the protection.
2> Suppose I wanted to subvert not only the WP, but use an unmapped physical
address. How then? (( I already tried MOVES with a function code of
$7 -- nice idea but no dice )).
This page table consists entirely of short format invalid descriptors and
early termination descriptors (I don't believe in actual page descriptors :-).
The solution must work on a 68020/68851 or 68030. Compatibility with the
bargain-basement 68040 MMU would be nice.
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|\_/| . ACK!, NAK!, EOT!, SOH!
{o O} . Bryce Nesbitt, Commodore-Amiga, Inc.
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