kexec-tools/SOURCES/92-crashkernel.install
2022-01-11 18:18:37 +00:00

147 lines
4.7 KiB
Bash
Executable File

#!/usr/bin/bash
COMMAND="$1"
KERNEL_VERSION="$2"
KDUMP_INITRD_DIR_ABS="$3"
KERNEL_IMAGE="$4"
grub_etc_default="/etc/default/grub"
ver_lt() {
[[ "$(echo -e "$1\n$2" | sort -V)" == $1$'\n'* ]] && [[ $1 != "$2" ]]
}
# Read crashkernel= value in /etc/default/grub
get_grub_etc_ck() {
[[ -e $grub_etc_default ]] && \
sed -n -e "s/^GRUB_CMDLINE_LINUX=.*\(crashkernel=[^\ \"]*\)[\ \"].*$/\1/p" $grub_etc_default
}
# Read crashkernel.default value of specified kernel
get_ck_default() {
ck_file="/usr/lib/modules/$1/crashkernel.default"
[[ -f "$ck_file" ]] && cat "$ck_file"
}
# Iterate installed kernels, find the kernel with the highest version that has a
# valid crashkernel.default file, exclude current installing/removing kernel
#
# $1: a string representing a crashkernel= cmdline. If given, will also check the
# content of crashkernel.default, only crashkernel.default with the same value will match
get_highest_ck_default_kver() {
for kernel in $(find /usr/lib/modules -maxdepth 1 -mindepth 1 -printf "%f\n" | sort --version-sort -r); do
[[ $kernel == "$KERNEL_VERSION" ]] && continue
[[ -s "/usr/lib/modules/$kernel/crashkernel.default" ]] || continue
echo "$kernel"
return 0
done
return 1
}
set_grub_ck() {
sed -i -e "s/^\(GRUB_CMDLINE_LINUX=.*\)crashkernel=[^\ \"]*\([\ \"].*\)$/\1$1\2/" "$grub_etc_default"
}
# Set specified kernel's crashkernel cmdline value
set_kernel_ck() {
kernel=$1
ck_cmdline=$2
entry=$(grubby --info ALL | grep "^kernel=.*$kernel")
entry=${entry#kernel=}
entry=${entry#\"}
entry=${entry%\"}
if [[ -z "$entry" ]]; then
echo "$0: failed to find boot entry for kernel $kernel"
return 1
fi
[[ -f /etc/zipl.conf ]] && zipl_arg="--zipl"
grubby --args "$ck_cmdline" --update-kernel "$entry" $zipl_arg
[[ $zipl_arg ]] && zipl > /dev/null ||:
}
case "$COMMAND" in
add)
# - If current boot kernel is using default crashkernel value, update
# installing kernel's crashkernel value to its default value,
# - If intalling a higher version kernel, and /etc/default/grub's
# crashkernel value is using default value, update it to installing
# kernel's default value.
inst_ck_default=$(get_ck_default "$KERNEL_VERSION")
# If installing kernel doesn't have crashkernel.default, just exit.
[[ -z "$inst_ck_default" ]] && exit 0
boot_kernel=$(uname -r)
boot_ck_cmdline=$(sed -n -e "s/^.*\(crashkernel=\S*\).*$/\1/p" /proc/cmdline)
highest_ck_default_kver=$(get_highest_ck_default_kver)
highest_ck_default=$(get_ck_default "$highest_ck_default_kver")
# Try update /etc/default/grub if present, else grub2-mkconfig could
# override crashkernel value.
grub_etc_ck=$(get_grub_etc_ck)
if [[ -n "$grub_etc_ck" ]]; then
if [[ -z "$highest_ck_default_kver" ]]; then
# None of installed kernel have a crashkernel.default,
# check for 'crashkernel=auto' in case of legacy kernel
[[ "$grub_etc_ck" == "crashkernel=auto" ]] && \
set_grub_ck "$inst_ck_default"
else
# There is a valid crashkernel.default, check if installing kernel
# have a higher version and grub config is using default value
ver_lt "$highest_ck_default_kver" "$KERNEL_VERSION" && \
[[ "$grub_etc_ck" == "$highest_ck_default" ]] && \
[[ "$grub_etc_ck" != "$inst_ck_default" ]] && \
set_grub_ck "$inst_ck_default"
fi
fi
# Exit if crashkernel is not used in current cmdline
[[ -z $boot_ck_cmdline ]] && exit 0
# Get current boot kernel's default value
boot_ck_default=$(get_ck_default "$boot_kernel")
if [[ $boot_ck_cmdline == "crashkernel=auto" ]]; then
# Legacy RHEL kernel defaults to "auto"
boot_ck_default="$boot_ck_cmdline"
fi
# If boot kernel doesn't have a crashkernel.default, check
# if it's using any installed kernel's crashkernel.default
if [[ -z $boot_ck_default ]]; then
[[ $(get_highest_ck_default_kver "$boot_ck_cmdline") ]] && boot_ck_default="$boot_ck_cmdline"
fi
# If boot kernel is using a default crashkernel, update
# installing kernel's crashkernel to new default value
if [[ "$boot_ck_cmdline" != "$inst_ck_default" ]] && [[ "$boot_ck_cmdline" == "$boot_ck_default" ]]; then
set_kernel_ck "$KERNEL_VERSION" "$inst_ck_default"
fi
exit 0
;;
remove)
# If grub default value is upgraded when this kernel was installed, try downgrade it
grub_etc_ck=$(get_grub_etc_ck)
[[ $grub_etc_ck ]] || exit 0
removing_ck_conf=$(get_ck_default "$KERNEL_VERSION")
[[ $removing_ck_conf ]] || exit 0
highest_ck_default_kver=$(get_highest_ck_default_kver) || exit 0
highest_ck_default=$(get_ck_default "$highest_ck_default_kver")
[[ $highest_ck_default ]] || exit 0
if ver_lt "$highest_ck_default_kver" "$KERNEL_VERSION"; then
if [[ $grub_etc_ck == "$removing_ck_conf" ]] && [[ $grub_etc_ck != "$highest_ck_default" ]]; then
set_grub_ck "$highest_ck_default"
fi
fi
exit 0
;;
esac