Why is filter driver being moved upward in stack?

NTDEV
1

Hi,
I have an upper filter driver that attaches to a scsi Qlogic pdo
(\Device\ql2200) in AddDevice. However, in subsequent calls to my driver I
am no longer attached directly to the Qlogic, but have been moved up above
the disk driver so that I’m now talking to \Device\Disk. Everything works
right now, but I’m wondering why this happens, and if it will bite me down
the road.

thanks
Andy

2

I think you are misinterpreting the data. You can’t get ‘moved up the
stack’.

Typically the confusion has to do with the PhysicalDeviceObject parameter
value passed to you in your AddDevice routine, and the DeviceObject value
returned to you in IoAttachDeviceToDeviceStack. I suspect that the PDO
passed to you is not the same value returned by IoAttachDeviceToDeviceStack.

-----Original Message-----
From: Andy LaRocco [mailto:xxxxx@charter.net]
Sent: Wednesday, March 27, 2002 10:23 AM
To: NT Developers Interest List
Subject: [ntdev] Why is filter driver being moved upward in stack?

Hi,
I have an upper filter driver that attaches to a scsi Qlogic pdo
(\Device\ql2200) in AddDevice. However, in subsequent calls
to my driver I am no longer attached directly to the Qlogic,
but have been moved up above the disk driver so that I’m now
talking to \Device\Disk. Everything works right now, but I’m
wondering why this happens, and if it will bite me down the road.

thanks
Andy

You are currently subscribed to ntdev as:
xxxxx@stratus.com To unsubscribe send a blank email to
%%email.unsub%%