File System Filter Driver Unload Problem

NTFSD
1

Hi,

I am doing the driver development. I am having problem when I call
fltunregister in preop_callback. Is there any way to execute it inside the
callback.(IRP_MJ_**).

Regards
Mansi

2

Yikes! FltUnregisterFilter inside a pre-op callback?

This will definitely cause a hang. There will be outstanding references on
the filter object, instance object, etc.

Try telling us why you are trying to call FltUnRegisterFilter in pre-op
callback.

Regards,

Ayush Gupta

Software Consultant & Owner,

AI Consulting

From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of mansi gupta
Sent: Wednesday, November 10, 2010 12:02 PM
To: Windows File Systems Devs Interest List
Subject: [ntfsd] File System Filter Driver Unload Problem

Hi,

I am doing the driver development. I am having problem when I call
fltunregister in preop_callback. Is there any way to execute it inside the
callback.(IRP_MJ_**).

Regards

Mansi

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3

“I am having problem when I call fltunregister in preop_callback.”

Explicitly declare and state your problem and post a stack trace.

You should not be of the belief people will understand what your
saying/thinking/trouble-shooting from two short sentences that
have zero technical details included other than a few key
nerd words…

4

hi,

I am extrating some information from hardware on the basis of which i want to unload it dynamically. so can you please help how i can do that. that’s why i was trying to call it in preop callback.

moreover the system hangs infinitely so there in no stack trace in windbg also.

5

So, your preop callback knows its time to unload, now communicate with your user mode application (you’ll write it), which will call unload on your driver and from your driver unload call FltUnregisterFilter.

6

My driver is boot time so is there any other way then communicating the user by which I can unload the filter driver.