Patch Name: PHKL_8733 Patch Description: s700 10.10 Adv VxFS (OnLineJFS) cumulative (no OmniStorage) Creation Date: 96/10/02 Post Date: 96/10/06 Repost: 96/11/15 The documentation was updated to clarify that this patch should not be installed on systems running OmniStorage. The checkinstall SD-UX control script will verify this and prevent installation on systems running OmniStorage. Hardware Platforms - OS Releases: s700: 10.10 Products: N/A Filesets: AdvJournalFS.VXFS-ADV-KRN Automatic Reboot?: Yes Status: General Superseded Critical: Yes PHKL_8733: CORRUPTION PHKL_8311: CORRUPTION Path Name: /hp-ux_patches/s700/10.X/PHKL_8733 Symptoms: PHKL_8733: Under OnlineJFS, when very large writes (e.g. >phymem/16) are done to JFS file(s), old data can appear in the middle of the newly written file(s). PHKL_8311: Data corruption can occur if HP OnLineJFS is installed and a very large write (over a megabyte) is done to a JFS file. A sequence of 1 - 8191 zeros can appear in the middle of the data just written. Defect Description: PHKL_8733: OnLineJFS breaks large write requests into multiple direct I/O's. Depending on the size of the data block, the beginnning and end of a direct I/O request may not align on the block boundaries. In these cases, the data is handled through buffer cache. After the first direct I/O, the subsequent iteration may begin with a write that has data starting in the middle of the buffer. If this write passes the current EOF, the buffer is simply allocated and filled with new data. If this buffer happens to be one that previously used to hold old data, the old data remains in the portion that is not overwritten by the new data. Writing this buffer to disk corrupts the file. The fix is to check against the correct file size so the first buffer of the subsequent iteration will be read in from disk to contain the correct data written in the last iteration. PHKL_8311: The problem can be reproduced with this test program: char buf[2097152]; main() { int fd; memset((void *)buf, 'A', sizeof(buf)); fd = creat("A.dat", 0644); write(fd, buf, 512); write(fd, buf, sizeof(buf)); } Every byte of the file should contain the character 'A'. This works fine on UFS. It also works on VxFS as long as HP OnLineJFS is not installed. But with HP OnLineJFS, a sequence of null bytes appears in the middle of the file (not at the boundary between the writes, but in the middle of the second write). SR: 1653180810 5003336933 Patch Files: /usr/conf/lib/libvxfs_adv.a(vx_dio.o) what(1) Output: /usr/conf/lib/libvxfs_adv.a(vx_dio.o): vx_dio.c $Date: 96/10/02 11:29:47 $ $Revision: 1.3.8 9.10 $ PATCH_10.10 (PHKL_8733) cksum(1) Output: 2336377526 9664 /usr/conf/lib/libvxfs_adv.a(vx_dio.o) Patch Conflicts: None Patch Dependencies: None Hardware Dependencies: None Other Dependencies: None Supersedes: PHKL_8311 Equivalent Patches: PHKL_8731: s700: 10.01 PHKL_8732: s800: 10.01 PHKL_8734: s800: 10.10 PHKL_8735: s700: 10.20 PHKL_8736: 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_8733 5a. For a standalone system, run swinstall to install the patch: swinstall -x autoreboot=true -x match_target=true \ -s /tmp/PHKL_8733.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_8733.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_8733. 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_8733.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_8733.depot of=/dev/rmt/0m bs=2k Special Installation Instructions: PHKL_8733 is a JFS patch that should not be installed on systems using the OmniStorage product. If you are using the OmniStorage product then using the methods taken to receive this patch please obtain the equivalent OmniStorage/JFS patch. If you cannot locate the patch, please contact your local HP support entity.