EBX: Contains the VM handle (always the Windows VM).
EBP: Points to the Windows VM's Client Registers.
Save everything that you use.
This routine is similar to SAVE_MESSAGE_MODE_STATE but saves the other "special" VM which is the forced planar state. Immediately before calling this function, the Main VDD will have executed a call to Interrupt 10h to setup Mode 12h. To restore the forced planar state during mode changes, this function copies all of the virtualized states to a special data segment CB data structure. Use this data structure to restore the state whenever you see the VDD's forced planar pseudo-VM handle (this is obtainable via the VDD service VDD_Get_Special_VM_IDs). All registers that are needed to restore for forced planar mode should be trapped at this time. For a description of the pseudo VM handles, see RESTORE_REGISTERS.
RESTORE_REGISTERS