static int is_stack(struct vm_area_struct *vma)
{
	/*
	 * We make no effort to guess what a given thread considers to be
	 * its "stack".  It's not even well-defined for programs written
	 * languages like Go.
	 */
	return vma->vm_start <= vma->vm_mm->start_stack &&
		vma->vm_end >= vma->vm_mm->start_stack;
}

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.