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!wdfkd.wdfdevext

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The !wdfkd.wdfdevext extension displays information that is associated with the DeviceExtension member of a Microsoft Windows Driver Model (WDM) DEVICE_OBJECT structure.

!wdfkd.wdfdevext DeviceExtension

Parameters

DeviceExtension
A pointer to a device extension.

DLL

Wdfkd.dll

Frameworks

KMDF 1, UMDF 1, UMDF 2

Additional Information

For more information, see Kernel-Mode Driver Framework Debugging.

Remarks

Here is an example for HdAudBus.sys, which is a KMDF driver. Use !devnode to find a device node that has HdAudBus as its function driver. Take the physical device object (PDO) from the output and pass it to !devstack. Take the device extension address from the output of !devstack and pass it to !wdfdevext.

0: kd> !devnode 0 1 hdaudbus
Dumping IopRootDeviceNode (= 0xffffe000002cfd30)
DevNode 0xffffe000009b7a50 for PDO 0xffffe00000226880
  InstancePath is "PCI\VEN_8086&DEV_293E&SUBSYS_2819103C&REV_02\3&33fd14ca&0&D8"
  ServiceName is "HDAudBus"
  ...
0: kd> !devstack 0xffffe00000226880
  !DevObj           !DrvObj            !DevExt           ObjectName
  ffffe00001351e20  \Driver\HDAudBus   ffffe000009a3c00  
> ffffe00000226880  \Driver\pci        ffffe000002269d0  NTPNP_PCI0009
!DevNode ffffe000009b7a50 :
  DeviceInst is "PCI\VEN_8086&DEV_293E&SUBSYS_2819103C&REV_02\3&33fd14ca&0&D8"
  ServiceName is "HDAudBus"
0: kd> *
0: kd> !wdfdevext ffffe000009a3c00
Device context is 0xffffe000009a3c00
    context:  dt 0xffffe000009a3c00 HDAudBus!HDAudioDeviceExtension (size is 0xa8 bytes)
    EvtCleanupCallback fffff80001f35950 HDAudBus!HdAudBusEvtDeviceCleanupCallback

!wdfdevice 0x00001fffff65c6e8                        
!wdfobject 0xffffe000009a3910

Here is an example for Wudfrd.sys, which is the function driver for the kernel-mode portion of a UMDF 2 driver stack. Use !devnode to find a device node that has Wudfrd as its function driver. Take the physical device object (PDO) from the output and pass it to !devstack. Take the device extension address from the output of !devstack and pass it to !wdfdevext.

0: kd> !devnode 0 1 wudfrd
Dumping IopRootDeviceNode (= 0xffffe000002cfd30)
DevNode 0xffffe00000a1e530 for PDO 0xffffe00000b15b00
  InstancePath is "ROOT\SAMPLE\0001"
  ServiceName is "WUDFRd"
  ...
0: kd> !devstack 0xffffe00000b15b00
  !DevObj           !DrvObj            !DevExt           ObjectName
  ffffe00000c11040  \Driver\WUDFRd     ffffe00000c11190  
> ffffe00000b15b00  \Driver\PnpManager 00000000  00000052
!DevNode ffffe00000a1e530 :
  DeviceInst is "ROOT\SAMPLE\0001"
  ServiceName is "WUDFRd"
0: kd> *
0: kd> !wdfdevext ffffe00000c11190
## Device context is 0xffffe00000c11190

##  UMDF Device Instances for this Redirector extension

  DriverManagerProcess: 0xffffe00003470500

  ImageName              Ver   DevStack           HostProcess        DeviceID      
  MyUmdf2Driver.dll      v2.0  0x000000a5a3ab5f70 0xffffe00000c32900  \Device\00000052