To track and manage kernel's crashkernel usage by kernel version,
each kernel package will include a crashkernel.default containing the
default `crashkernel=` value of that kernel. So we can use a hook to
update the kernel cmdline of new installed kernel accordingly.
Put it after all other grub boot loader setup hooks, so it can simply
call grubby to modify the kernel cmdline.
Signed-off-by: Kairui Song <kasong(a)redhat.com>
---
92-crashkernel.install | 143 +++++++++++++++++++++++++++++++++++++++++
kexec-tools.spec | 4 ++
2 files changed, 147 insertions(+)
create mode 100755 92-crashkernel.install
diff --git a/92-crashkernel.install b/92-crashkernel.install
new file mode 100755
index 0000000..d12f32e
--- /dev/null
+++ b/92-crashkernel.install
@@ -0,0 +1,143 @@
+#!/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
+ # 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" "$inst_ck_default"
+ fi
+ ;;
+
+remove)
+ # If grub default value is upgraded when this kernel was installed, try downgrade it
+ grub_etc_ck=$(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
+ ;;
+esac
diff --git a/kexec-tools.spec b/kexec-tools.spec
index 8fed959..ec327da 100644
--- a/kexec-tools.spec
+++ b/kexec-tools.spec
@@ -40,6 +40,7 @@ Source29: kdump.sysconfig.aarch64
Source30: 60-kdump.install
Source31: kdump-logger.sh
Source32: mkfadumprd
+Source33: 92-crashkernel.install
#######################################
# These are sources for mkdumpramfs
@@ -66,6 +67,7 @@ Requires: dracut >= 050
Requires: dracut-network >= 050
Requires: dracut-squash >= 050
Requires: ethtool
+Requires: grubby
BuildRequires: make
BuildRequires: zlib-devel elfutils-devel glib2-devel bzip2-devel ncurses-devel bison flex
lzo-devel snappy-devel
BuildRequires: pkgconfig intltool gettext
@@ -210,6 +212,7 @@ install -m 644 %{SOURCE15}
$RPM_BUILD_ROOT%{_mandir}/man5/kdump.conf.5
install -m 644 %{SOURCE16} $RPM_BUILD_ROOT%{_unitdir}/kdump.service
install -m 755 -D %{SOURCE22}
$RPM_BUILD_ROOT%{_prefix}/lib/systemd/system-generators/kdump-dep-generator.sh
install -m 755 -D %{SOURCE30}
$RPM_BUILD_ROOT%{_prefix}/lib/kernel/install.d/60-kdump.install
+install -m 755 -D %{SOURCE32}
$RPM_BUILD_ROOT%{_prefix}/lib/kernel/install.d/92-crashkernel.install
%ifarch %{ix86} x86_64 ppc64 s390x ppc64le aarch64
install -m 755 makedumpfile-%{mkdf_ver}/makedumpfile
$RPM_BUILD_ROOT/usr/sbin/makedumpfile
@@ -360,6 +363,7 @@ done
%{_unitdir}/kdump.service
%{_prefix}/lib/systemd/system-generators/kdump-dep-generator.sh
%{_prefix}/lib/kernel/install.d/60-kdump.install
+%{_prefix}/lib/kernel/install.d/92-crashkernel.install
%doc News
%license COPYING
%doc TODO
--
2.31.1