strange NdisWaitEvent?

Hi dear all,
As we know , NdisWaitEvent will call KeWaitForSingleObject with the
passed NDIS_EVENT(8196b198), but the following stack trace show that
KeWaitForSingleObject is passed NULL event object , which cause a
bugcheck 0xa . Could someone explain this for me ? Or I’ve missed
something ? thanks in advance.
ChildEBP RetAddr Args to Child
f5e905bc 80533747 00000003 f5e90918 00000000 nt!RtlpBreakWithStatusInstruction
f5e90608 8053421e 00000003 00000000 804dd11d nt!KiBugCheckDebugBreak+0x19
f5e909e8 804e287f 0000000a 00000000 00000002 nt!KeBugCheck2+0x574
f5e909e8 804dd11d 0000000a 00000000 00000002 nt!KiTrap0E+0x233
f5e90a9c f98b268a 00000000 00000000 00000000 nt!KeWaitForSingleObject+0x186
f5e90ac0 f5b0e032 8196b198 00000000 00000000 NDIS!NdisWaitEvent+0x39
f5e90adc f98c2803 f5e90ba8 8196b188 f5e90afc myfw!MyFwUnbindAdapterHandler+0x68
f5e90bb0 f98c29b3 81a56cd0 00000000 81a69ad0 NDIS!ndisUnbindProtocol+0x157
f5e90be4 f98baf5f 81992a58 81a9de18 000000a1
NDIS!ndisHandleProtocolUnbindNotification+0xce
f5e90bf4 f98baee6 00000000 81992a58 81992ac8 NDIS!ndisHandleUModePnPOp+0x9a
f5e90c18 f98baa10 81ad8f90 81b7b9c8 81992a58 NDIS!ndisHandlePnPRequest+0x163
f5e90c34 804e47f7 81b7b8b0 81992a58 806f0070 NDIS!ndisDispatchRequest+0x78
f5e90c44 80568f81 81992ac8 81ad8f90 81992a58 nt!IopfCallDriver+0x31
f5e90c58 8057ba9f 81b7b8b0 81992a58 81ad8f90 nt!IopSynchronousServiceTail+0x70
f5e90d00 8058ffd7 000005d4 00000000 00000000 nt!IopXxxControlFile+0x611
f5e90d34 804df7ec 000005d4 00000000 00000000 nt!NtDeviceIoControlFile+0x2a
f5e90d34 7c92e4f4 000005d4 00000000 00000000 nt!KiFastCallEntry+0xf8
022ef20c 7c92d26c 7c801675 000005d4 00000000 ntdll!KiFastSystemCallRet
022ef210 7c801675 000005d4 00000000 00000000 ntdll!NtDeviceIoControlFile+0xc
022ef270 755c113d 000005d4 00170008 02f0ac88 kernel32!DeviceIoControl+0xdd

Sorry . I forgot to initialize the EVENT object