vm_unmap_mmio
(void) vm_unmap_mmio(vmx->vm, DEFAULT_APIC_BASE, PAGE_SIZE);
err = vm_unmap_mmio(vm, seg->gpa, seg->len);
(void) vm_unmap_mmio(vm, seg->gpa, seg->len);
int vm_unmap_mmio(struct vm *vm, vm_paddr_t gpa, size_t len);