My KMDF USB driver is stable, passes DTM on xp/vista/win7. But from time to time I get a report that it does not work on a virtualized usb port. I yet have to get a failing unit in my lab and see the failure.
It is a simple driver with a continuous reader on an interrupt pipe. Is there any reason to doubt the robustness of KMDF/USB over a virtualized port?
Well, the WDF team nor Microsoft tesms virtualized usb ports with KMDF. KMDF expects the USB io contract from the lower stack, so I would guess failure is coming from the virtualized device in some weird edge condition
d
-----Original Message-----
From: xxxxx@lists.osr.com [mailto:xxxxx@lists.osr.com] On Behalf Of xxxxx@yahoo.com
Sent: Wednesday, November 24, 2010 2:43 PM
To: Windows System Software Devs Interest List
Subject: [ntdev] kmdf usb drivrer and thin clients
My KMDF USB driver is stable, passes DTM on xp/vista/win7. But from time to time I get a report that it does not work on a virtualized usb port. I yet have to get a failing unit in my lab and see the failure.
It is a simple driver with a continuous reader on an interrupt pipe. Is there any reason to doubt the robustness of KMDF/USB over a virtualized port?
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xxxxx@yahoo.com wrote:
My KMDF USB driver is stable, passes DTM on xp/vista/win7. But from time to time I get a report that it does not work on a virtualized usb port. I yet have to get a failing unit in my lab and see the failure.
It is a simple driver with a continuous reader on an interrupt pipe. Is there any reason to doubt the robustness of KMDF/USB over a virtualized port?
No, but there is reason to doubt virtualized USB ports. My web cameras
didn’t work reliably in VMs until I tried the XP Environment in Windows
7. There, it’s pretty solid.
–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.