Bugcheck 0x7e

Hi,
My driver bugchecks after the AddDevice routine. The meaning is
SYSTEM_THREAD_EXCEPTION_NOT_HANDLED with code STATUS_ACCESS_VIOLATION.
I need help debugging this issue.

*** Fatal System Error: 0x0000007e
(0xC0000005,0x8051FCDD,0xFD5BB930,0xFD5BB630)

Break instruction exception - code 80000003 (first chance)

A fatal system error has occurred.
Debugger entered on first try; Bugcheck callbacks have not been invoked.

A fatal system error has occurred.

Connected to Windows XP 2600 x86 compatible target, ptr64 FALSE
Loading Kernel Symbols

Loading unloaded module list

Loading User Symbols
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*
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* Bugcheck Analysis
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Use !analyze -v to get detailed debugging information.

BugCheck 7E, {c0000005, 8051fcdd, fd5bb930, fd5bb630}

Probably caused by : ntoskrnl.exe ( nt!IovUtilMarkDeviceObject+9 )

Followup: MachineOwner

nt!RtlpBreakWithStatusInstruction:
805103fa cc int 3
kd> !analyze -v
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*
*
* Bugcheck Analysis
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*
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SYSTEM_THREAD_EXCEPTION_NOT_HANDLED (7e)
This is a very common bugcheck. Usually the exception address pinpoints
the driver/function that caused the problem. Always note this address
as well as the link date of the driver/image that contains this address.
Arguments:
Arg1: c0000005, The exception code that was not handled
Arg2: 8051fcdd, The address that the exception occurred at
Arg3: fd5bb930, Exception Record Address
Arg4: fd5bb630, Context Record Address

Debugging Details:

EXCEPTION_CODE: (NTSTATUS) 0xc0000005 - The instruction at “0x%08lx”
referenced memory at “0x%08lx”. The memory could not be “%s”.

FAULTING_IP:
nt!IovUtilMarkDeviceObject+9
8051fcdd 8b81b0000000 mov eax,[ecx+0xb0]

EXCEPTION_PARAMETER1: fd5bb930

CONTEXT: fd5bb630 – (.cxr fffffffffd5bb630)
eax=00000000 ebx=00000000 ecx=00000000 edx=00000002 esi=ffbc5960
edi=00000000
eip=8051fcdd esp=fd5bb9f8 ebp=fd5bba04 iopl=0 nv up ei pl nz na pe
nc
cs=0008 ss=0010 ds=0023 es=0023 fs=0030 gs=0000
efl=00010202
nt!IovUtilMarkDeviceObject+9:
8051fcdd 8b81b0000000 mov eax,[ecx+0xb0]
Resetting default context

DEFAULT_BUCKET_ID: DRIVER_FAULT

BUGCHECK_STR: 0x7E

LAST_CONTROL_TRANSFER: from 804d6946 to 8051fcdd

STACK_TEXT:
fd5bb9f4 804d6946 8112a0e8 00000000 fd5bba60
nt!IovUtilMarkDeviceObject+0x9
fd5bba04 80554a53 81133190 00000000 00000001 nt!IovUtilMarkStack+0x54
fd5bbacc 8055a657 00000000 05000001 81133190
nt!PipCallDriverAddDevice+0x404
fd5bbd18 8055af62 81248590 00000001 00000000
nt!PipProcessDevNodeTree+0x147
fd5bbd4c 804d7125 00000003 80549fc0 8054eddc
nt!PiProcessReenumeration+0x5e
fd5bbd74 804ed629 00000000 00000000 81259020
nt!PipDeviceActionWorker+0x133
fd5bbdac 8057c73a 00000000 00000000 00000000 nt!ExpWorkerThread+0xfe
fd5bbddc 805124c1 804ed556 00000001 00000000
nt!PspSystemThreadStartup+0x34
00000000 00000000 00000000 00000000 00000000 nt!KiThreadStartup+0x16

FOLLOWUP_IP:
nt!IovUtilMarkDeviceObject+9
8051fcdd 8b81b0000000 mov eax,[ecx+0xb0]

FOLLOWUP_NAME: MachineOwner

SYMBOL_NAME: nt!IovUtilMarkDeviceObject+9

MODULE_NAME: nt

IMAGE_NAME: ntoskrnl.exe

DEBUG_FLR_IMAGE_TIMESTAMP: 3d6de35c

STACK_COMMAND: .cxr fffffffffd5bb630 ; kb

BUCKET_ID: 0x7E_nt!IovUtilMarkDeviceObject+9

Followup: MachineOwner

TIA
Dayalan.