The ObDereferenceObjectDeferDelete routine decrements the reference count for the given object, checks for object retention, and avoids deadlocks.
ObDereferenceObjectDeferDelete例程减少指定对象的引用计数，检查对象保留(不明白,检查对象需不需要删除??)，并且避免死锁。
语法：
VOID ObDereferenceObjectDeferDelete(
_In_ PVOID Object
);
参数：
Object [in]
A pointer to the body of the object.
指向对象实体的指针
返回值
None
备注：
ObDereferenceObjectDeferDelete is similar to ObDereferenceObject except that,
when the reference count of the object reaches zero,
the object manager passes the object deletion request to a worker thread.
Therefore, the deletion later occurs at IRQL = PASSIVE_LEVEL.
ObDereferenceObjectDeferDelete与ObDereferenceObject类似，除了，当引用计数为 0 时，对象管理器传递对象删除请求到工作线程。
因此，当之后IRQL=PASSIVE_LEVEL时，发生删除。
Use ObDereferenceObjectDeferDelete for any object when the immediate deletion by the current thread of the object (by using ObDereferenceObject)
might result in a deadlock.
Google翻译的，我不懂...
For example, such a deadlock can occur if ObDereferenceObject is used to dereference a Kernel Transaction Manager (KTM) object
when a higher level driver on the driver stack is holding a lock.
例如，使用ObDereferenceObject为Kernel Transaction Manager(KTM) 对象解引用 ，当一个驱动栈上的高层驱动持有锁时，会发生死锁。
To avoid such deadlocks, use ObDereferenceObjectDeferDelete instead of ObDereferenceObject to dereference KTM objects.
为了避免死锁，应使用ObDereferenceObjectDeferDelete代替ObDereferenceObject 对KTM对象解外用。
Note For information about object permanence and attributes, see ObDereferenceObject.
更多对象持久和属性的信息，参见ObDereferenceObject。
依赖项：
操作系统： Available in Windows Vista and later versions of Windows operating systems.Windows Vista及以上版本
头文件： Wdm.h (include Fltkernel.h or Ntifs.h)
库： Contained in Ntoskrnl.lib.
IRQL： <= DISPATCH_LEVEL