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by MereInterest 2167 days ago
I don't understand, and couldn't get any information from the article either. If the data are decrypted within the VM, then it is still decrypted at that point, and the host machine can read it.
2 comments

The data is transparently encrypted and decrypted specifically within the processor. The OS kernel on the host machine doesn't have access to the unencrypted contents of the guest VM's memory.

> I don't understand, and couldn't get any information from the article either.

See this wiki article for more info on this class of technology: https://en.wikipedia.org/wiki/Data_in_use

You can access memory within a VM, not outside of a VM. Host machine with a hypervisor is not within a VM instance, so it will not be able to read your VM memory. The memory is encrypted all the time, but when the instruction has to be executed on CPU, memory controllers (only and only have access to the keys of this VM) decrypt the instruction to execute it on cpu in clear. For FHE, cpu instructions are executed on AES encrypted blocks, and will take significant time, so not very practical today. Does it make sense?