in which case it is treated as an entirely new device. See
vmbus_onoffer_rescind().
+
+Confidential VMBus
+------------------
+
+The confidential VMBus provides the control and data planes where
+the guest doesn't talk to either the hypervisor or the host. Instead,
+it relies on the trusted paravisor. The hardware (SNP or TDX) encrypts
+the guest memory and the register state also measuring the paravisor
+image via using the platform security processor to ensure trsuted and
+confidential computing.
+
+To support confidential communication with the paravisor, a VmBus client
+will first attempt to use regular, non-isolated mechanisms for communication.
+To do this, it must: