> Some MPIC implementations tend to generate a spurrious IRQ in the case > of level IRQs going away. IE. they still remember an event occurred and > interrupt the processor, but on IACK return the spurious vector. However > that isn't guaranteed to be the case and it is perfectly ok (and a good > idea) for the PIC to just stop asserting the external interrupt line if > the original device interrupt goes away (and it's configured as level > sensitive). That will happen if the IRQ goes away while the cpu is performing the IACK sequence. If the IRQ goes away while the cpu has interrupts masked then the cpu won't start the interrupt sequence and then try to read a vector when no interrupt is pending. David -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
