Patch Name: PHKL_11545 Patch Description: s700 10.20 SCSI tape cumulative patch Creation Date: 97/06/27 Post Date: 97/07/02 Hardware Platforms - OS Releases: s700: 10.20 Products: N/A Filesets: OS-Core.CORE-KRN ProgSupport.C-INC Automatic Reboot?: Yes Status: General Superseded Critical: Yes PHKL_11545: PANIC Path Name: /hp-ux_patches/s700/10.X/PHKL_11545 Symptoms: PHKL_11545: - Fixes an intermittent panic when opening a tape device on the HSC bus - Improves performance for wide SCSI tape devices connected via the HSC bus - Allows DLT4000 devices to perform odd-sized writes PHKL_10421: When reading a tape on a 7980S tape drive, reading a partial record fails and returns I/O Error. If a tape device receives a bus reset the device will rewind. Following this, when the device is closed, the driver will write EOF marks at the beginning of the tape causing the remaining data to be unusable. When a tape device is opened for write access and the media is write protected the driver returns I/O Error, which can be ambiguous. EPERM (Permission denied) is a more descriptive error. PHKL_8755: Fixes a bug with Exabyte tape drives that caused append writes (those not at BOT) to be in non-compressed mode when using the BEST density setting. PHKL_8506: This patch changes the behavior of the open() call with a write protected tape. The open() will now fail with EIO if the mode is not O_RDONLY. PHKL_8128: Device files other than those that use the BEST density do not work. Opening such a device file returns EINVAL. This happens only on DLT tape drives. PHKL_8028: Without immediate reporting enabled a DLT tape drive will take several seconds for each filemark written. If a user application is writing many filemarks to a tape the performance will be poor. This patch enables immediate reporting of filemarks, which should improve performance for an application that writes many filemarks to a tape. Defect Description: PHKL_11545: - The tape driver will occasionally panic on the open of a tape device which is attached to the HSC bus. The panic is caused when a tape device responds with a "check condition" very early in the open process. The problem is intermittent and can not be reliably reproduced. - Patches PHKL_10417 through PHKL_10422 changed the way the driver negotiated with the device for narrow (8 bit) or wide (16 bit) transfers. This fixed a problem with 7980S tape drives, but caused the driver to never correctly negotiate for wide transfers. Any wide device on a wide interface would suffer a performance degradation because the driver was throttling it down to 8 bit transfers instead of 16 bit transfers. - Because of problems with transfering an odd number of bytes over a wide bus, the driver prevents doing an odd sized write to a wide device. The DLT4000 is a narrow device, but it is differential so it attaches to a wide bus. The driver was looking at the bus size, rather than the device type, to determine the transfer size and so it was blocking odd-sized transfers to DLT4000 devices even though these should be allowed. Writing an odd-sized record to a DLT4000 would return an EIO error. PHKL_10421: 7980S problem was caused by a change in the SCSI interface driver which caused the interface to negotiate for synchronous even when the driver had not enabled that negotiation. The 7980S drive is not SCSI-2 compliant, and has problems with synchronous negotiation in some places. Other changes were enhancements - no defect. PHKL_8755: The Exabyte bug can be reproduced by writing a large (100 Mb) file to an Exabyte drive using the 'BEST' device file in 'no rewind' mode, then writing the same file again to the same device. The first write will be substantially faster because it is compressed while following writes are not compressed. PHKL_8506: Before this patch the open() call did not look at media write protection. A write() to a write protected tape would fail, but an open() with FWRITE mode would succeed. This change was made to make the GSC driver behave the same as the NIO driver. PHKL_8128: A 'break' statement was missing from the end of a switch, causing the code to fall through to an error return. Device files which specify 'BEST' density work, but a DLT device with a density other than BEST will not open. PHKL_8028: A flag in the driver indicates, for each device type, whether or not immediate reporting should be enabled for filemarks. That flag was not being set for DLT drives. To reproduce, write a short C program that writes 20 blocks of 1K bytes, each separated by a filemark. Performance will be substantially better with this patch applied. SR: 1653215020 4701329417 4701342089 5003329078 5003359489 Patch Files: /usr/conf/h/mtio.h /usr/conf/lib/libhp-ux.a(scsi_tape.o) /usr/include/sys/mtio.h what(1) Output: /usr/conf/h/mtio.h: mtio.h $Date: 97/02/06 10:40:37 $ $Revision: 1.24.98 .5 $ PATCH_10.20 (PHKL_8755) /usr/conf/lib/libhp-ux.a(scsi_tape.o): scsi_tape.c $Date: 97/06/27 10:05:17 $ $Revision: 1. 8.98.16 $ PATCH_10.20 (PHKL_11545) /usr/include/sys/mtio.h: mtio.h $Date: 97/02/06 10:40:37 $ $Revision: 1.24.98 .5 $ PATCH_10.20 (PHKL_8755) cksum(1) Output: 1634341172 25693 /usr/conf/h/mtio.h 2409975805 68068 /usr/conf/lib/libhp-ux.a(scsi_tape.o) 1634341172 25693 /usr/include/sys/mtio.h Patch Conflicts: None Patch Dependencies: None Hardware Dependencies: None Other Dependencies: None Supersedes: PHKL_8028 PHKL_8128 PHKL_8506 PHKL_8755 PHKL_10421 Equivalent Patches: PHKL_11546: s800: 10.20 Patch Package Size: 160 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_11545 5a. For a standalone system, run swinstall to install the patch: swinstall -x autoreboot=true -x match_target=true \ -s /tmp/PHKL_11545.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_11545.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_11545. 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_11545.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_11545.depot of=/dev/rmt/0m bs=2k Special Installation Instructions: None