Files
s390-tools/zdev/dracut/95zdev/zdev-lib.sh
Steffen Maier 73c46a3056 zdev/dracut: fix kdump by only activating required devices
This prevents out-of-memory (OOM) situations in the kdump crashkernel
environment.

Please note that the new dracut module 95zdev-kdump and the new library
zdev-lib.sh need to be packaged into the same (core) (sub)package as
95zdev.

This patch introduces a new dracut module "zdev-kdump", which is used
instead of module "zdev" when building a kdump initrd:

1. Ignore all persistently configured block devices and disable zfcp auto
LUN scanning => minimize the number of SCSI devices enabled during kdump.

2. Do not rely on chzdev's persistent configuration => work with systems
that do not use chzdev for persistent device configuration.

The detection of kdump is based on strict hostonly mode and on $IN_KDUMP.
See also
https://src.fedoraproject.org/rpms/kexec-tools commit
4eedcae5e154 ("dracut-module-setup.sh: don't include multipath-hostonly")
and https://github.com/dracutdevs/dracut commits
35e86ac117ac ("Merge 90-multipath-hostonly and 90-multipath")
a695250ec7db ("Introduce tri-state hostonly mode")
and
https://src.fedoraproject.org/rpms/kexec-tools/blob/rawhide/f/mkdumprd#_17
https://src.fedoraproject.org/rpms/kexec-tools/blob/rawhide/f/dracut-module-setup.sh#_23.
The detection of kdump is also based on kdump_needed() in
https://github.com/openSUSE/kdump/blob/master/dracut/module-setup.sh.

Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2023-03-03 09:58:40 +01:00

25 lines
853 B
Bash

#
# Copyright IBM Corp. 2023
#
# s390-tools is free software; you can redistribute it and/or modify
# it under the terms of the MIT license. See LICENSE for details.
#
#
# 95zdev/zdev-lib.sh
# Common shell library functionality for 95zdev and 95zdev-kdump.
#
is_kdump() {
# https://src.fedoraproject.org/rpms/kexec-tools/c/4eedcae5e1540690a3761857fe2e692774c44960
# https://src.fedoraproject.org/rpms/kexec-tools/blob/rawhide/f/mkdumprd
# https://src.fedoraproject.org/rpms/kexec-tools/blob/rawhide/f/dracut-module-setup.sh
if [[ $hostonly && "$hostonly_mode" == "strict" && -n "$IN_KDUMP" ]]; then
return 0
fi
# https://github.com/openSUSE/kdump/blob/master/dracut/module-setup.sh
if [[ " $dracutmodules $add_dracutmodules $force_add_dracutmodules " == *\ kdump\ * ]]; then
return 0
fi
return 1
}