static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
{
	unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);

	memslot->dirty_bitmap = kvzalloc(dirty_bytes, GFP_KERNEL);
	if (!memslot->dirty_bitmap)
		return -ENOMEM;

	return 0;
}

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.