I poked around a little with respect to use of
System Management Mode in FreeMWare.

I was looking into it's use to play games with
the selector RPL and descriptor DPL values.  But
I doesn't seem well suited for this, not so much
because of the capabilites, but access to getting
into SMM.

First, we'd be up against multiple chipsets to
deal with.  This didn't worry me too much.  But
a big problem is that the SMRAM memory space is
locked down after being initialized by the BIOS
(at least on the chipset I looked up).  The
lock was one way and can only be unlocked
upon a power-on reset.  This effect being we
couldn't write our own SMM handler to the
SMM memory space.

Unless I'm missing something, this doesn't
appear to be such a viable option.  Perhaps
there's some kind of system reset and CMOS
reg 0x0f trickery to do to override the BIOS lockdown,
but I think we'd better not play with that.

Guess it's back to old-fashion virtualization
strategies...

-Kevin

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