Locating MDL in Windbg

NTDEV
1

Are there any commands in windbg to list the MDLs allocated by, say, MmAllocatePagesForMdl? Just to check if someone forgets to free the MDLs

2

!poolfind Mdl
or
!poolfind -x “dt nt!_MDL @$extret” Mdl
(that’s actually in !poolfind help)

Kris

On Wed, Jan 20, 2016 at 10:05 AM, wrote:
> Are there any commands in windbg to list the MDLs allocated by, say, MmAllocatePagesForMdl? Just to check if someone forgets to free the MDLs
>
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3

Thx, but I’m a bit confused. MSDN says !poolfind should be like this:

!poolfind TagString [PoolType]
!poolfind TagValue [PoolType]

(https://msdn.microsoft.com/en-us/library/windows/hardware/ff564696(v=vs.85).aspx)

So, how come there is a -x parameter? Did I miss something?

4

Yeah, I don’t think it’s documented anywhere except in ‘usage page’
displayed when you execute ‘!poolfind’ with no args. Also this is in
Debugging Tools for Windows v. 10.0.10240. I don’t think earlier
versions had it.

Kris

On Wed, Jan 20, 2016 at 12:18 PM, wrote:
> Thx, but I’m a bit confused. MSDN says !poolfind should be like this:
>
> !poolfind TagString [PoolType]
> !poolfind TagValue [PoolType]
>
> (https://msdn.microsoft.com/en-us/library/windows/hardware/ff564696(v=vs.85).aspx)
>
> So, how come there is a -x parameter? Did I miss something?
>
>
>
> —
> NTDEV is sponsored by OSR
>
> Visit the list online at: http:
>
> MONTHLY seminars on crash dump analysis, WDF, Windows internals and software drivers!
> Details at http:
>
> To unsubscribe, visit the List Server section of OSR Online at http:

–
Kris</http:></http:></http:>

5

‘Mdl’ is the tag used by IoAllocateMdl.

MmAllocatePagesForMdl uses ’ Mmdi’ (currently; could change in the future etc.)

-----Original Message-----
From: xxxxx@lists.osr.com [mailto:xxxxx@lists.osr.com] On Behalf Of Krzysztof Uchronski
Sent: Wednesday, January 20, 2016 3:54 AM
To: Windows System Software Devs Interest List
Subject: Re: [ntdev] Locating MDL in Windbg

!poolfind Mdl
or
!poolfind -x “dt nt!_MDL @$extret” Mdl
(that’s actually in !poolfind help)

Kris

On Wed, Jan 20, 2016 at 10:05 AM, wrote:
> Are there any commands in windbg to list the MDLs allocated by, say, MmAllocatePagesForMdl? Just to check if someone forgets to free the MDLs