ICH 8/9/10 machines with Intel gigabit part integrated (82566/82567)
share the system Flash space with all the other system devices, BIOS,
etc. The gigabit region is the currently only "unprotected" region I
know of. It is never directly memory mapped, but the registers that
program to it are memory mapped from our BAR1, like Tim said, possibly
only requiring an errant write of a few bits of ones, to erase it (I've
been trying to confirm that)
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