>>> drivers/pci/intr_remapping.c: In function 'irq_2_iommu_alloc':
>>> drivers/pci/intr_remapping.c:72: error: 'boot_cpu_id' undeclared (first use in this function)
>>> drivers/pci/intr_remapping.c:72: error: (Each undeclared identifier is reported only once
>>> drivers/pci/intr_remapping.c:72: error: for each function it appears in.)