ECO NUMBER:     ALPDRIV09_062
             PRODUCT:        OpenVMS Alpha OPERATING SYSTEM 6.2
             UPDATE PRODUCT: OpenVMS Alpha OPERATING SYSTEM 6.2




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1  KIT NAME:

     ALPDRIV09_062 for OpenVMS Alpha V6.2 only.


2  KITS SUPERSEDED BY THIS KIT:

     None


3  KIT DESCRIPTION:

     3.1  Version(s) of OpenVMS to which this kit may be applied:

     OpenVMS Alpha V6.2, V6.2-1H1, V6.2-1H2, V6.2-1H3


     3.2  In order to receive the full fixes  listed  in  this  kit  the
          following remedial kits also need to be installed:

     None


     3.3  Files patched or replaced:


      o  [SYS$LDR]SYS$PUDRIVER.EXE (new image)



4  PROBLEMS ADDRESSED IN ALPDRIV09_062 KIT


      o  System crash.  The system attempts to place a CDRP into a  wait
         state.   However,  the  CDRP is already in another incompatible
         wait state.

         The system ran out  of  messages  and  placed  CDRPs  into  the
         message  wait  queue.   A  response is received that frees up a
         message which is placed in the response ring.  This causes  the
         response  ring  to  be  full.   The  system  then finds another
         message that has become available.  The response ring  is  full
         so  the  system checks for message waiters.  It finds a waiting
         CDRP and attempts to start it, which works.   The  system  then
         attempts to start the next waiter but finds no more messages so
         it looks for one.  When one is found it calls back into the SCS
         routine  to  start  the  first  waiter,  which is the CDRP that
         started this loop.  Eventually the  code  will  return  to  the
         first CDRP waiter that was already started in an inner loop and
         either wait or start it again which causes  it  to  be  in  two
         states at the same time.

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                                                           15 May 1997


         This problem will only occur with a KCM44 controller because it
         issues 45 credits which are enough to exhaust the message queue
         if there is enough IO.



5  KIT INSTALLATION RATING:

     The following kit  installation  rating,  based  upon  current  CLD
     information,  is provided to serve as a guide as to which customers
     should apply this remedial kit.  (Reference attached Disclaimer  of
     Warranty and Limitation of Liability Statement)

     INSTALLATION RATING:

     INSTALL_2 : To  be  installed  by  all  customers  using  the  following
     feature(s):

     Any customer using the SYS$PUDRIVER.


6  INSTALLATION INSTRUCTIONS:

     Install this kit with the VMSINSTAL utility  by  logging  into  the
     SYSTEM account, and typing the following at the DCL prompt:

         @SYS$UPDATE:VMSINSTAL ALPDRIV09_062 [location of the saveset]

     The saveset location may be a tape drive, or a disk directory  that
     contains the kit saveset.

     System should be rebooted after successful installation of the kit.
     If  you  have  other  nodes in your VMScluster, they should also be
     rebooted in order to make use of the new image(s).


     Copyright  (c)  Digital  Equipment  Corporation,  1997  All  Rights
     Reserved.   Unpublished rights reserved under the copyright laws of
     the United States.

     The software contained on this media is proprietary to and embodies
     the  confidential  technology  of  Digital  Equipment  Corporation.
     Possession, use, or dissemination of  the  software  and  media  is
     authorized  only  pursuant  to a valid written license from Digital
     Equipment Corporation.

     DISCLAIMER OF WARRANTY AND LIMITATION OF LIABILITY

     THIS PATCH IS PROVIDED AS IS, WITHOUT WARRANTY OF  ANY  KIND.   ALL
     EXPRESS  OR  IMPLIED  CONDITIONS,  REPRESENTATIONS  AND WARRANTIES,
     INCLUDING ANY IMPLIED  WARRANTY  OF  MERCHANTABILITY,  FITNESS  FOR
     PARTICULAR PURPOSE, OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED TO THE
     EXTENT PERMITTED BY APPLICABLE LAW.  IN NO EVENT  WILL  DIGITAL  BE
     LIABLE  FOR  ANY  LOST REVENUE OR PROFIT, OR FOR SPECIAL, INDIRECT,
     CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER  CAUSED  AND
     REGARDLESS  OF  THE  THEORY OF LIABILITY, WITH RESPECT TO ANY PATCH

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                                                           15 May 1997


     MADE AVAILABLE HERE OR TO THE USE OF SUCH PATCH.