A processing system may include a first processing unit for a first partition and a second processing unit for a second partition. To support power management, an interrupt handler in the processing system may receive a standby command from an operating system. In response to receiving the standby command, the interrupt handler may cause the first processing unit to transition into a reduced power mode. After the second partition detects a wake event, the second partition may cause the first processing unit to transition out of the reduced power mode. In an example embodiment, the interrupt handler executes within the first partition, and the first processing unit transitions into the reduced power mode by entering an idle loop within the interrupt handler. The first partition may determine from within the idle loop whether the first partition has been released from the low power state. Other embodiments are described and claimed.