VOID IrpCancelRoutine(IN PDEVICE_OBJECT fdo, IN PIRP Irp)

{

	PDEVICE_EXTENSION pdx = (PDEVICE_EXTENSION)fdo->DeviceExtension;



	IoAcquireRemoveLock(&pdx->RemoveLock, Irp);

	

	//  Release the global cancel spin lock.  

	//  Do this while not holding any other spin locks so that we exit at the right IRQL.

	IoReleaseCancelSpinLock(Irp->CancelIrql);



	if( Irp == pdx->pBufIrp) 

	{ 

		KeInitializeEvent(&event, NotificationEvent, FALSE);



		//pdx->LowerDeviceObject, 已经初始化完成

		irp = IoBuildDeviceIoControlRequest(IOCTL_INTERNAL_USB_SUBMIT_URB,

						pdx->LowerDeviceObject,

						NULL,

						0,

						NULL,

						0,

						TRUE,

						&event,

						&ioStatus);



		ntStatus = IoCallDriver(pdx->LowerDeviceObject, irp);

		if(ntStatus == STATUS_PENDING)

		{

                       //在此处死等，在其他线程上先文中不存在这个问题，取消历程中，存在此问题。为啥

			status = KeWaitForSingleObject(pdx->phExitEvent,Executive,ernelMode,FALSE,NULL);

 		}

	//...其他处理

	}



	//取消IRP

}