Help: KMDF Filter Driver Installation

NTDEV
1

Hello Experts,

I would like to place my upper filter driver between disk class and partmgr. I followed the installation instruction as per http://www.osronline.com/article.cfm?article=446 and also I added “UpperFilters” key value as “PartMgr MyFilterDrvr” into the registry path “HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class{4D36E967-E325-11CE-BFC1-08002BE10318}”.

Installation was successful. I was able to filter all IOs from application layer (raw IO via IOmeter). But when I tried to initialize the disk, looks like partition manager sends it own IO which does not come to my filter.

Looks like myfilter driver sits on top of partmgr. Devicetree utility confirms the same.

Not sure what I’m missing.

Any help/comments are welcome!!!

Thanks,
-Raj P.

2

First swap the order of the UpperFilters so that it is “MyFilterDrvr
PartMgr”, second use OSR’s DeviceTree
http://www.osronline.com/article.cfm?article=97 to verify what is above
what.

Don Burn
Windows Filesystem and Driver Consulting
Website: http://www.windrvr.com
Blog: http://msmvps.com/blogs/WinDrvr

“xxxxx@gmail.com” wrote in message
news:xxxxx@ntdev:

> Hello Experts,
>
> I would like to place my upper filter driver between disk class and partmgr. I followed the installation instruction as per http://www.osronline.com/article.cfm?article=446 and also I added “UpperFilters” key value as “PartMgr MyFilterDrvr” into the registry path “HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class{4D36E967-E325-11CE-BFC1-08002BE10318}”.
>
> Installation was successful. I was able to filter all IOs from application layer (raw IO via IOmeter). But when I tried to initialize the disk, looks like partition manager sends it own IO which does not come to my filter.
>
> Looks like myfilter driver sits on top of partmgr. Devicetree utility confirms the same.
>
> Not sure what I’m missing.
>
> Any help/comments are welcome!!!
>
> Thanks,
> -Raj P.

3

Yes, I did try swapping the order of the UpperFilters. But unfortunately there is no change the order. As mentioned, I used DeviceTree and verified that myfilterdrvr is always on top of “PartMgr”.

I also used another utility from bustrace. Results are as below.

Filter Driver Load Order http://www.bustrace.com

Upper Class Filter: myfilterdrvr
Upper Class Filter: PartMgr
Device Object: SSDSA2SH 032G1GN INTE SCSI Disk Device
Lower Filter Drivers: No Lower Filter Drivers specified for this device

Driver Name: partmgr.sys
File Location: c:\windows\system32\drivers
File Description: Partition Management Driver
File Version: 6.1.7600.16385 (win7_rtm.090713-1255) [6.1.7601.17514]
Product Name: Microsoft? Windows? Operating System
Product Version: 6.1.7600.16385 [6.1.7601.17514]
Company Name: Microsoft Corporation

Thanks,
-Raj P.

4

Hi Don Burn,

Changing the order in registry did help. Now myfilter driver is below
PartMgr.

Looks like I messed up something when I tried yesterday. That’s why it was
not working yesterday.

Thanks for your help.
-Raj P.

On Tue, Sep 4, 2012 at 6:25 PM, wrote:

> Yes, I did try swapping the order of the UpperFilters. But unfortunately
> there is no change the order. As mentioned, I used DeviceTree and verified
> that myfilterdrvr is always on top of “PartMgr”.
>
> I also used another utility from bustrace. Results are as below.
>
> ----------------------------------------------------
> Filter Driver Load Order http://www.bustrace.com
> ----------------------------------------------------
>
> Upper Class Filter: myfilterdrvr
> Upper Class Filter: PartMgr
> Device Object: SSDSA2SH 032G1GN INTE SCSI Disk Device
> Lower Filter Drivers: No Lower Filter Drivers specified for this device
>
> Driver Name: partmgr.sys
> File Location: c:\windows\system32\drivers
> File Description: Partition Management Driver
> File Version: 6.1.7600.16385 (win7_rtm.090713-1255)
> [6.1.7601.17514]
> Product Name: Microsoft? Windows? Operating System
> Product Version: 6.1.7600.16385 [6.1.7601.17514]
> Company Name: Microsoft Corporation
>
> Thanks,
> -Raj P.
>
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