rpms/kexec-tools
5
0
Fork 0
Code Issues Pull Requests Releases Activity

reset kernel crashkernel for the special case where the kernel is updated right after kexec-tools

Browse Source 
Resolves: bz1895258
Upstream: Fedora
Conflict: None

commit 5e8c751c39
Author: Coiby Xu <coxu@redhat.com>
Date:   Thu Dec 2 17:19:50 2021 +0800

    reset kernel crashkernel for the special case where the kernel is updated right after kexec-tools

    When kexec-tools updates the default crashkernel value, it will try to
    reset the existing installed kernels including the currently running
    kernel. So the running kernel could have different kernel cmdline
    parameters from /proc/cmdline. When installing a kernel after updating
    kexec-tools, /usr/lib/kernel/install.d/20-grub.install would be called
    by kernel-install [1] which would use /proc/cmdline to set up new kernel's
    cmdline. To address this special case, reset the new kernel's crashkernel
    and fadump value to the value that would be used by running kernel after
    rebooting by the installation hook. One side effect of this commit is it
    would reset the installed kernel's crashkernel even currently running kernel
    don't use the default crashkernel value after rebooting. But I think this
    side effect is a benefit for the user.

    The implementation depends on kernel-install which run the scripts in
    /usr/lib/kernel/install.d passing the following arguments,

      add KERNEL-VERSION $BOOT/MACHINE-ID/KERNEL-VERSION/ KERNEL-IMAGE [INITRD-FILE ...]

    An concrete example is given as follows,
      add 5.11.12-300.fc34.x86_64 /boot/e986846f63134c7295458cf36300ba5b/5.11.12-300.fc34.x86_64 /lib/modules/5.11.12-300.fc34.x86_64/vmlinuz

    kernel-install could be started by the kernel package's RPM scriplet [2].
    As mentioned in previous commit "try to reset kernel crashkernel when
    kexec-tools updates the default crashkernel value", kdumpctl has difficulty
    running in RPM scriptlet fore CoreOS. But rpm-ostree ignores all kernel hooks,
    there is no need to disable the kernel hook for CoreOS/Atomic/Silverblue. But a
    collaboration between rpm-ostree and kexec-tools is needed [3] to take care
    of this special case.

    Note the crashkernel.default support is dropped.

    [1] https://www.freedesktop.org/software/systemd/man/kernel-install.html
    [2] https://src.fedoraproject.org/rpms/kernel/blob/rawhide/f/kernel.spec#_2680
    [3] https://github.com/coreos/rpm-ostree/issues/2894

    Reviewed-by: Pingfan Liu <piliu@redhat.com>
    Reviewed-by: Philipp Rudo <prudo@redhat.com>
    Signed-off-by: Coiby Xu <coxu@redhat.com>

Signed-off-by: Coiby Xu <coxu@redhat.com>
This commit is contained in:
Coiby Xu 2022-01-05 11:53:22 +08:00 committed by Tao Liu
parent 224984355d
commit 2589c40c4e
2 changed files with 32 additions and 134 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

135
92-crashkernel.install
View File

@ -5,142 +5,9 @@ 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 "$highest_ck_default"
fi
fi
kdumpctl reset-crashkernel-for-installed_kernel "$KERNEL_VERSION"
exit 0
;;
esac

31
kdumpctl
View File

@ -1602,6 +1602,32 @@ reset_crashkernel_after_update()
done
}
reset_crashkernel_for_installed_kernel()
{
local _installed_kernel _running_kernel _crashkernel _crashkernel_running
local _dump_mode_running _fadump_val_running
if ! _installed_kernel=$(_find_kernel_path_by_release "$1"); then
exit 1
fi
if ! _running_kernel=$(_get_current_running_kernel_path); then
derror "Couldn't find current running kernel"
exit
fi
_crashkernel=$(get_grub_kernel_boot_parameter "$_installed_kernel" crashkernel)
_crashkernel_running=$(get_grub_kernel_boot_parameter "$_running_kernel" crashkernel)
_dump_mode_running=$(get_dump_mode_by_kernel "$_running_kernel")
_fadump_val_running=$(get_grub_kernel_boot_parameter "$_kernel" fadump)
if [[ $_crashkernel != "$_crashkernel_running" ]]; then
if _update_grub "$_installed_kernel" "$_crashkernel_running" "$_dump_mode_running" "$_fadump_val_running"; then
echo "kexec-tools has reset $_installed_kernel to use the new default crashkernel value $_crashkernel_running"
fi
fi
}
if [[ ! -f $KDUMP_CONFIG_FILE ]]; then
derror "Error: No kdump config file found!"
exit 1
@ -1672,6 +1698,11 @@ main()
reset_crashkernel_after_update
fi
;;
reset-crashkernel-for-installed_kernel)
if [[ $(kdump_get_conf_val auto_reset_crashkernel) != no ]]; then
reset_crashkernel_for_installed_kernel "$2"
fi
;;
*)
dinfo $"Usage: $0 {estimate|start|stop|status|restart|reload|rebuild|reset-crashkernel|propagate|showmem}"
exit 1