DOCUMENT:Q132694 08-AUG-2001 [winnt] TITLE :Windows NT May Hang With DEC Pathworks Installed PRODUCT :Microsoft Windows NT PROD/VER:3.50 3.51 OPER/SYS: KEYWORDS:kb3rdparty kbnetwork ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server versions 3.5, 3.51 ------------------------------------------------------------------------------- SYMPTOMS ======== Windows NT servers with two or more CPUs and DEC Pathworks for Windows NT, versions 4.1 or 4.1b installed, stop responding (hang). No STOP message appears, and there no hardware or software errors are logged. CAUSE ===== This problem occurs because DEC Pathworks for Windows NT acquires and releases spinlocks in reverse order in the NetBIOS over DECNet code. This causes the computer to hang when one CPU tries to acquire a lock still held by another CPU. The following is a simplified description of how this condition occurs: 1. On Processor 0, a DEC Pathworks for Windows NT routine acquires Lock A spinlock, and then, while holding Lock A, tries to acquire Lock B spinlock. 2. On Processor 1, a DEC Pathworks for Windows NT routine acquires Lock B spinlock, and then, while holding Lock B, tries to acquire Lock A spinlock. STATUS ====== DEC Pathworks is currently testing a fix for this problem. The products included here are manufactured by vendors independent of Microsoft; we make no warranty, implied or otherwise, regarding these products' performance or reliability. Additional query words: 3.50 3.51 prodnt spin lock ====================================================================== Keywords : kb3rdparty kbnetwork Technology : kbWinNTsearch kbWinNT351search kbWinNT350search kbWinNTSsearch kbWinNTS351 kbWinNTS350 kbWinNTS351search kbWinNTS350search Version : 3.50 3.51 ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.