kho_scratch_overlap
if (WARN_ON(kho_scratch_overlap(virt_to_phys(elm), PAGE_SIZE)))
if (WARN_ON(kho_scratch_overlap(virt_to_phys(chunk), PAGE_SIZE)))
if (WARN_ON(kho_scratch_overlap(pfn << PAGE_SHIFT, PAGE_SIZE << order)))
if (WARN_ON(kho_scratch_overlap(start_pfn << PAGE_SHIFT,
bool kho_scratch_overlap(phys_addr_t phys, size_t size);