Multiple machine state registers are included in a processor core to permit distinction between use of hardware facilities by applications, supervisory threads and the hypervisor. All facilities are initially disabled by the hypervisor when a partition is initialized. When any access is made to a disabled facility, the hypervisor receives an indication of which facility was accessed and sets a corresponding hardware flag in the hypervisor's machine state register. When an application attempts to access a disabled facility, the supervisor managing the operating system image receives an indication of which facility was accessed and sets a corresponding hardware flag in the supervisor's machine state register. The multiple register implementation permits the supervisor to determine whether particular hardware facilities need to have their state saved when an application context swap occurs and the hypervisor can determine which hardware facilities need to have their state saved when a partition swap occurs.