AMD Zen Microarchitecture: Dual Schedulers, Micro-Op Cache and Memory Hierarchy
SEV (Secure Encrypted Virtualization, [1]) is a hugely interesting feature that will be available with Zen. Once it's mature and perfected, it would allow you to securely run a VM in the cloud that is protected against someone who controls the hypervisor. And you'd also be able to attest that indeed you're running in such a protected VM.<p>How do you protect against someone controlling the hypervisor? Read the paper. But the high level is to encrypt memory using keys that cannot leave the processor and are only available to a specific VM ASID (Address Space Identifier), assisted by a secure firmware similar to the Secure Enclave. Attestation uses an on-chip certificate signed by an AMD master key during fabrication.<p>There were some discussions on this on the linux-kernel mailing list [2]. As I understand it, the current generation of SEV is still somewhat leaky, but there's no fundamental reason why those leaks cannot be closed.<p>[1] <a href="http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/12/AMD_Memory_Encryption_Whitepaper_v7-Public.pdf" rel="nofollow">http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/...</a>
[2] <a href="http://www.mail-archive.com/linux-doc@vger.kernel.org/msg02578.html" rel="nofollow">http://www.mail-archive.com/linux-doc@vger.kernel.org/msg025...</a>