I guess it would be pretty rude/unlikely for these opcodes to get reused
in other implementations... But couldn't you make the page trap
instead, rather than relying on an instruction fault?
Is this compatible with Xen's (and other's) use of cpuid? That is,
0x40000000 returns a hypervisor-specific signature in e[bcd]x, and eax
has the max hypervisor leaf.
J
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