4 ms·
> The ARM architecture design makes it near impossible for an early boot backdoor to, say, run your OS in an undetectable VM too. Can you explain this? It does
by als0 5y ago
> The ARM architecture design makes it near impossible for an early boot backdoor to, say, run your OS in an undetectable VM too.
Can you explain this? It doesn’t sound right.
- marcan_42 5y agoThe M1 does not support nested virtualization, so if you put a VM hypervisor under an OS, the OS knows it's running in guest mode. Making it transparent would imply implementing nested virtualization in software in an undetectable way, which is nigh impossible given the way the architecture is designed. Undefined/illegal/HV-privileged instructions don't trap to the hypervisor, nor does the "am I a guest?" instruction. You have to get into full guest code analysis and patching territory. It's a giant mess, and cannot be done without massive performance overhead.