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diff --git a/Documentation/s390/zfcpdump.txt b/Documentation/s390/zfcpdump.txt deleted file mode 100644 index b064aa59714d..000000000000 --- a/Documentation/s390/zfcpdump.txt +++ /dev/null @@ -1,48 +0,0 @@ -The s390 SCSI dump tool (zfcpdump) - -System z machines (z900 or higher) provide hardware support for creating system -dumps on SCSI disks. The dump process is initiated by booting a dump tool, which -has to create a dump of the current (probably crashed) Linux image. In order to -not overwrite memory of the crashed Linux with data of the dump tool, the -hardware saves some memory plus the register sets of the boot CPU before the -dump tool is loaded. There exists an SCLP hardware interface to obtain the saved -memory afterwards. Currently 32 MB are saved. - -This zfcpdump implementation consists of a Linux dump kernel together with -a user space dump tool, which are loaded together into the saved memory region -below 32 MB. zfcpdump is installed on a SCSI disk using zipl (as contained in -the s390-tools package) to make the device bootable. The operator of a Linux -system can then trigger a SCSI dump by booting the SCSI disk, where zfcpdump -resides on. - -The user space dump tool accesses the memory of the crashed system by means -of the /proc/vmcore interface. This interface exports the crashed system's -memory and registers in ELF core dump format. To access the memory which has -been saved by the hardware SCLP requests will be created at the time the data -is needed by /proc/vmcore. The tail part of the crashed systems memory which -has not been stashed by hardware can just be copied from real memory. - -To build a dump enabled kernel the kernel config option CONFIG_CRASH_DUMP -has to be set. - -To get a valid zfcpdump kernel configuration use "make zfcpdump_defconfig". - -The s390 zipl tool looks for the zfcpdump kernel and optional initrd/initramfs -under the following locations: - -* kernel: <zfcpdump directory>/zfcpdump.image -* ramdisk: <zfcpdump directory>/zfcpdump.rd - -The zfcpdump directory is defined in the s390-tools package. - -The user space application of zfcpdump can reside in an intitramfs or an -initrd. It can also be included in a built-in kernel initramfs. The application -reads from /proc/vmcore or zcore/mem and writes the system dump to a SCSI disk. - -The s390-tools package version 1.24.0 and above builds an external zfcpdump -initramfs with a user space application that writes the dump to a SCSI -partition. - -For more information on how to use zfcpdump refer to the s390 'Using the Dump -Tools book', which is available from -http://www.ibm.com/developerworks/linux/linux390. |