Patch Name:  PHKL_10633

Patch Description: s700 10.10 Informix process hang, pfdat page unlocking

Creation Date: 97/04/07

Post Date:  97/04/10

Hardware Platforms - OS Releases:
        s700: 10.10

Products: N/A

Filesets:
        OS-Core.CORE-KRN

Automatic Reboot?: Yes

Status: General Release

Critical:
        Yes
        PHKL_10633: HANG
        PHKL_8156: HANG

Path Name:  /hp-ux_patches/s700/10.X/PHKL_10633

Symptoms:
        PHKL_10633:
        Multiple processes sharing a memory region hang when
        trying to acquire the region lock, while the owner
        of the region lock waits infinitely for a page in the
        region to be unlocked.

        PHKL_8156:
        When running Informix version 7.13 on HP_UX 10.10, the
        Informix oninit process hangs.  This can be seen with
        glance.  The oninit process is blocked on VM.

        The general symptom is that a process is sleeping
        interruptibly, forever, inside a write() or read().

Defect Description:
        PHKL_10633:
        The vaslockpages() routine brings in a specified range
        of pages and acquires the pfdat locks for these pages.
        In the case that it does not have the correct access
        rights of all these pages due to the lack of free memory,
        it will unlock the pages and return an ENOMEM. The bug
        is that it unlocks an incorrect number of pages and leaves
        one page locked infinitely during each back out.

        PHKL_8156:
        When doing I/O on a range of pages, the kernel needs to wire
        down the pages, faulting them in if necessary.  If the
        process gets a signal in the middle of this, it aborts the
        attempt, but unfortunately didnt unwire the pages it had
        already wired down by then.

        To reproduce the defect, Informix was run with a heavy load,
        after a few hours, the Informix oninit/tbinit process are
        blocked, and one of them shows up as being blocked on VM (as
        reported by Glance).

SR:
        5003327171 5003359463

Patch Files:
        /usr/conf/lib/libhp-ux.a(vm_misc.o)

what(1) Output:
        /usr/conf/lib/libhp-ux.a(vm_misc.o):
                vm_misc.c     $Date: 97/04/07 10:01:58 $ $Revision:
                        1.10.89.12 $ PATCH_10.10 (PHKL_10633)

cksum(1) Output:
        3464372455 10052 /usr/conf/lib/libhp-ux.a(vm_misc.o)

Patch Conflicts: None

Patch Dependencies:  None

Hardware Dependencies:  None

Other Dependencies:  None

Supersedes:
        PHKL_8156

Equivalent Patches:
        PHKL_10634:
        s800: 10.10

        PHKL_10460:
        s700: 10.20

        PHKL_10461:
        s800: 10.20

Patch Package Size:  70 Kbytes

Installation Instructions:
        Please review all instructions and the Hewlett-Packard
        SupportLine User Guide or your Hewlett-Packard support terms
        and conditions for precautions, scope of license,
        restrictions, and, limitation of liability and warranties,
        before installing this patch.
        ------------------------------------------------------------
        1. Back up your system before installing a patch.

        2. Login as root.

        3. Copy the patch to the /tmp directory.

        4. Move to the /tmp directory and unshar the patch:

                cd /tmp
                sh PHKL_10633

        5a. For a standalone system, run swinstall to install the
            patch:

                swinstall -x autoreboot=true -x match_target=true \
                        -s /tmp/PHKL_10633.depot

        5b. For a homogeneous NFS Diskless cluster run swcluster on the
            server to install the patch on the server and the clients:

                swcluster -i -b

            This will invoke swcluster in the interactive mode and
            force all clients to be shut down.

            WARNING: All cluster clients must be shut down prior to the
                     patch installation.  Installing the patch while the
                     clients are booted is unsupported and can lead to
                     serious problems.

            The swcluster command will invoke an swinstall session in which
            you must specify:

                alternate root path  -  default is /export/shared_root/OS_700
                source depot path    -  /tmp/PHKL_10633.depot

            To complete the installation, select the patch by choosing
            "Actions -> Match What Target Has" and then "Actions -> Install"
            from the Menubar.

        5c. For a heterogeneous NFS Diskless cluster:

                - run swinstall on the server as in step 5a to install
                  the patch on the cluster server.

                - run swcluster on the server as in step 5b to install
                  the patch on the cluster clients.

        By default swinstall will archive the original software in
        /var/adm/sw/patch/PHKL_10633.  If you do not wish to retain a
        copy of the original software, you can create an empty file
        named /var/adm/sw/patch/PATCH_NOSAVE.

        Warning: If this file exists when a patch is installed, the
                 patch cannot be deinstalled.  Please be careful
                 when using this feature.

        It is recommended that you move the PHKL_10633.text file to
        /var/adm/sw/patch for future reference.

        To put this patch on a magnetic tape and install from the
        tape drive, use the command:

                dd if=/tmp/PHKL_10633.depot of=/dev/rmt/0m bs=2k

Special Installation Instructions:  None