Toward Confidential Cloud Computing

Confidential VMs allow tenants to have a fully backward-compatible VM experience running existing unmodified applications. In the background, systems record and check attestations to verify the security guarantees and make them auditable. Placing entire VMs in TEEs is important for fast and easy adoption, but it also causes some problems. For example, the administrator for the VM has full read/write control over the VM, which is too coarse in many cases. Another concern is that the TCB for a VM is large: a VM image is far more than just a kernel and an application; it includes a large number of system services.