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Re: [MiNT] Crash log



Hello!

As we've already talked about, this is most likely a hardware bug in
the clones, Milan/Hades. On both my milan/hades applications are allowed
to read/write this area. Generating access faults to the first 2Kb of
system RAM is a task done by the address-logic in real Atari hardware,
and indipendant of the PMMU settings. Even ST's sets supervisor
restrictions to this area, it has no PMMU ;-)

For Milan I can answer the following:

Milan always use the MMU, Milan use 8kb pages. First versions of Bootblock/TOS setup the the first page (the one from 0) to be supervisor protected.

But in this area are also some VDI variables (or something like that) that are defined to be non-supervisor accessible. So for MagiC (and TOS/NVDI) compatibility the first page was changed to be non-supervisor accessible.

I discussed a lot woth Michael Schwingen about this but he didn't changed it back or made it configurable. The only way is that the kernel change back the primary MMU tree so that the first page is supervisor only. Don't know if that have negative side effect for applications.


Regards,
Frank

--
ATARI FALCON 060 // MILAN 060
--------------------------------
http://sparemint.atariforge.net/
e-Mail: fnaumann@freemint.de