A system and method is disclosed for managing system management interrupts
in a multiprocessor system. The system described herein includes multiple
processors, each of which may be directly coupled to memory. A primary
processor will recognize the initiation of a system management interrupt.
The primary processor will write a reason code to a storage location and
set a watchdog timer, the expiration of which causes all of the
processors of the system to enter a system management mode. After all of
the processors have entered system management mode, it is determined if
the reason code of the storage location corresponds to certain
software-based system management interrupts. If so, the system management
interrupt is handled by the local processors. Following the handling of
the system management interrupt by the local processor, a signal is sent
to each of the other processors to cause the processors to exit system
management mode.