static long madvise_willneed(struct vm_area_struct *vma,
			     struct vm_area_struct **prev,
			     unsigned long start, unsigned long end)
{
	struct file *file = vma->vm_file;

#ifdef CONFIG_SWAP
	if (!file) {
		*prev = vma;
		force_swapin_readahead(vma, start, end);
		return 0;
	}

	if (shmem_mapping(file->f_mapping)) {
		*prev = vma;
		force_shm_swapin_readahead(vma, start, end,
					file->f_mapping);
		return 0;
	}
#else
	if (!file)
		return -EBADF;
#endif

	if (IS_DAX(file_inode(file))) {
		/* no bad return value, but ignore advice */
		return 0;
	}

	*prev = vma;
	start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
	if (end > vma->vm_end)
		end = vma->vm_end;
	end = ((end - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;

	force_page_cache_readahead(file->f_mapping, file, start, end - start);
	return 0;
}
The program contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.