Dear SCO Customer,

Support Level Supplement (SLS) PTF4002B, the Virtual Memory Supplement for 
UnixWare, corrects the following problems:

   1.   Systems with more than 1Gb of physical memory could run out of
        kernel virtual memory (for example, fork() fail with EAGAIN),
        because the carve_kvspace() algorithm allocated too small a
        proportion of kernel virtual memory to segkvn and to segmap.

   2.   Systems with more than 2Gb of physical memory needed fixed
        mip and sip programs for booting from /stand, but SCO UnixWare 
        2.1.3 Update (update213) installation forgot to copy these from 
        /etc/initprog.

   3.   PANIC: hat_pteload - changing existing mapping:pte = XXXXXXXX
        was caused by page_get_aligned() omitting to recheck pages
        free, when allocating physically contiguous pages at runtime
        (for example, when using the e3H network card driver).

   4.   PANIC in swap_free() was caused by page_abort_l() resetting
        the p_invalid flag before anon_hashout() or memfs_hashout()
        could act upon it, when deleting a swap area.


SLS PTF4002B contains these files:

        /etc/conf/pack.d/mem/Driver_atup.o
        /etc/conf/pack.d/mem/Driver_mp.o


Software Notes and Recommendations
----------------------------------

SLS PTF4002B should only be installed on these releases:

      SCO UnixWare Application Server Release 2.1.0, 2.1.1, 2.1.2, 2.1.3
      SCO UnixWare Personal Edition Release 2.1.0, 2.1.1, 2.1.2, 2.1.3

It is recommended that you upgrade to UnixWare Release 2.1.3 by applying the
SCO UnixWare 2.1.3 Update, if you have not already done so.  If you are 
installing SLS PTF4002B on Release 2.1.0, SLS PTF3028B must be installed 
first.  If you are installing PTF4002B on Release 2.1.1 or 2.1.2, PTF3131B 
must be installed first.

If the osmp package is installed after SLS PTF4002B has been installed, 
SLS PTF4002B should be installed again afterwards.

2Gb MEMRANGE boot restrictions can be removed after installing SLS PTF4002B 
on UnixWare 2.1.3.  The correct 4Gb /stand/mip and /stand/sip files remain 
even after SLS PTF4002B has been removed.

Notes on the fixes included in this SLS can be found in:

   /var/sadm/pkg/ptf4002/install/ptf4002.txt


Installation Instructions
-------------------------

1. Download the ptf4002b.Z file to the /tmp directory on your machine.

2. As root, uncompress the file and add the SLS to your system
   using these commands:

        $ su
        Password: <type your root password>
        # uncompress /tmp/ptf4002b.Z
        # pkgadd -d /tmp/ptf4002b
        # rm /tmp/ptf4002b

3. Reboot the system after installing this SLS.  



Removal Instructions
--------------------

1. As root, remove the SLS using these commands:

        $ su
        Password: <type your root password>
        # pkgrm ptf4002

2. Reboot the system after removing this SLS.


If you have questions regarding this SLS, or the product on
which it is installed, please contact your software supplier.

We appreciate your business.

SCO Support Services