show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
{
	struct mm_struct *mm = vma->vm_mm;
	struct file *file = vma->vm_file;
	vm_flags_t flags = vma->vm_flags;
	unsigned long ino = 0;
	unsigned long long pgoff = 0;
	unsigned long start, end;
	dev_t dev = 0;
	const char *name = NULL;

	if (file) {
		struct inode *inode = file_inode(vma->vm_file);
		dev = inode->i_sb->s_dev;
		ino = inode->i_ino;
		pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
	}

	start = vma->vm_start;
	end = vma->vm_end;
	show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino);

	/*
	 * Print the dentry name for named mappings, and a
	 * special [heap] marker for the heap:
	 */
	if (file) {
		seq_pad(m, ' ');
		seq_file_path(m, file, "\n");
		goto done;
	}

	if (vma->vm_ops && vma->vm_ops->name) {
		name = vma->vm_ops->name(vma);
		if (name)
			goto done;
	}

	name = arch_vma_name(vma);
	if (!name) {
		if (!mm) {
			name = "[vdso]";
			goto done;
		}

		if (vma->vm_start <= mm->brk &&
		    vma->vm_end >= mm->start_brk) {
			name = "[heap]";
			goto done;
		}

		if (is_stack(vma))
			name = "[stack]";
	}

done:
	if (name) {
		seq_pad(m, ' ');
		seq_puts(m, name);
	}
	seq_putc(m, '\n');
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.