DOCUMENT:Q152194  08-AUG-2001  [winnt]
TITLE   :Stop 0x0A When NWNBLNK Accesses Memory in Free Pool
PRODUCT :Microsoft Windows NT
PROD/VER:winnt:3.51
OPER/SYS:
KEYWORDS:kbnetwork

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The information in this article applies to:

 - Microsoft Windows NT Workstation version 3.51 
 - Microsoft Windows NT Server version 3.51 
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SYMPTOMS
========

Computers that use NWLink NetBIOS may experience blue stop screens with a
bugcheck code of

   0x0A: IRQL_NOT_LESS_OR_EQUAL.

Examination of a crashdump, or a live debug, usually reveals that the exception
occurred in function KeAcquireSpinLock called from function
HandleConnectionZero, and is caused by NWLNKNB accessing memory that is either
in free pool or which has been acquired by another process.


CAUSE
=====

Due to incorrect synchronization logic, there is an exposure in NWNBLNK that
causes a bugcheck when multiple requests are processed for the same NWNBLNK
connection. If one of the requests is a disconnect, in some rare circumstances
the disconnect is completed first, freeing the memory structure used for the
NWNBLNK connection structure. When processing of the remaining requests resume,
a Stop 0x0A results when attempting to access the now freed (and possibly
reused) connection structure.

Due to the nature of this problem it occurs very infrequently. When the problem
does occur, it is most likely to be seen on faster computers, particularly on
multi-processor computers, such as multi-processor DEC Alpha servers.

RESOLUTION
==========

Apply the hotfix described below or upgrade to Windows NT 4.0.

STATUS
======

Microsoft has confirmed this to be a problem in Windows NT version 3.51. A
supported fix is now available, but is not fully regression-tested and should be
applied only to systems experiencing this specific problem. Unless you are
severely impacted by this specific problem, Microsoft recommends that you wait
for the next Service Pack that contains this fix. Contact Microsoft Product
Support Services for more information.


Additional query words: 3.51 csnw nwcs gsnw prodnt

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Keywords          : kbnetwork 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNT351search kbWinNTW351search kbWinNTW351 kbWinNTSsearch kbWinNTS351 kbWinNTS351search
Version           : winnt:3.51

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