static AddressSpace *memory_region_to_address_space(MemoryRegion *mr)
{
    AddressSpace *as;

    while (mr->container) {
        mr = mr->container;
    }
    QTAILQ_FOREACH(as, &mr->uc->address_spaces, address_spaces_link) {
        if (mr == as->root) {
            return as;
        }
    }
    return NULL;
}