update_vector
void (*update_vector)(unsigned int cpu, unsigned int vector, bool set);
if (apic->update_vector)
apic->update_vector(cpu, vector, set);
update_vector(cpu, APIC_IRR, vector, true);
update_vector(cpu, SAVIC_ALLOWED_IRR, vector, set);
update_vector(cpu, APIC_ISR, vec, false);
.update_vector = savic_update_vector,