fix #3761: proxmox-boot: add pin/unpin for kernel-version

The 2 commands follow the mechanics of p-b-t kernel add/remove in
writing the desired abi-version to a config-file in /etc/kernel and
actually modifying the boot-loader configuration upon p-b-t refresh.

A dedicated new file is used instead of writing the version (with some
kind of annotation) to the manual kernel list to keep parsing the file
simple (and hopefully also cause fewer problems with manually edited
files)

For systemd-boot we write the entry into the loader.conf on the ESP(s)
instead of relying on the `bootctl set-default` mechanics (bootctl(1))
which write the entry in an EFI-var. This was preferred, because of a
few reports of unwriteable EFI-vars on some systems (e.g. DELL servers
have a setting preventing writing EFI-vars from the OS). The rationale
in `Why not simply rely on the EFI boot menu logic?` from [0] also
makes a few points in that direction.

For grub the following choices were made:
* write the pinned version (or actually the menu-path leading to it)
  to a snippet in /etc/default/grub.d instead of editing the grub.cfg
  files on the partition. Mostly to divert as little as possible from
  the grub-workflow I assume people are used to.
* the 'root-device-id' part of the menu-entries is parsed from
  /boot/grub/grug.cfg since it was stable (the same on all ESPs and in
  /boot/grub), saves us from copying the part of "find device behind
  /, mangle it if zfs/btrfs, call grub_probe a few times" part of
  grub-mkconfig - and seems a bit more robust

Tested with a BIOS and an UEFI VM with / on ZFS.

[0] https://systemd.io/BOOT_LOADER_SPECIFICATION/

Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
Reviewed-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Tested-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
This commit is contained in:
Stoiko Ivanov 2022-02-11 16:15:42 +01:00 committed by Thomas Lamprecht
parent 151a54703c
commit 83a41a1a03
3 changed files with 90 additions and 0 deletions

View File

@ -286,6 +286,13 @@ list_kernels() {
echo ""
echo "Automatically selected kernels:"
echo "$boot_kernels"
pinned_kernel="$(get_first_line "$PINNED_KERNEL_CONF")"
if [ -n "$pinned_kernel" ]; then
echo ""
echo "Pinned kernel:"
echo "${pinned_kernel}"
fi
}
usage() {
@ -296,6 +303,8 @@ usage() {
warn " $0 clean [--dry-run]"
warn " $0 refresh [--hook <name>]"
warn " $0 kernel <add|remove> <kernel-version>"
warn " $0 kernel pin <kernel-version>"
warn " $0 kernel unpin"
warn " $0 kernel list"
warn " $0 status [--quiet]"
warn " $0 help"
@ -323,6 +332,15 @@ help() {
echo " add/remove pve-kernel with ABI <kernel-version> to list of synced kernels, in addition to automatically selected ones."
echo " NOTE: you need to manually run 'refresh' once you're finished with adding/removing kernels from the list"
echo ""
echo "USAGE: $0 kernel pin <kernel-version>"
echo ""
echo " pin pve-kernel with ABI <kernel-version> as the default entry to be booted."
echo " NOTE: you need to manually run 'refresh' once you're finished with pinning kernels"
echo ""
echo "USAGE: $0 kernel unpin"
echo ""
echo " unpin sets the latest kernel as the default entry (undoes a previous pin)"
echo ""
echo "USAGE: $0 kernel list"
echo ""
echo " list kernel versions currently selected for inclusion on ESPs."
@ -392,6 +410,28 @@ status() {
fi
}
pin_kernel() {
ver="$1"
if [ -z "$ver" ]; then
warn "E: <kernel-version> is mandatory"
warn ""
exit 1
fi
if [ ! -e "/boot/vmlinuz-$ver" ]; then
warn "E: no kernel image found in /boot for '$ver', not setting default."
exit 1
fi
echo "$ver" > "$PINNED_KERNEL_CONF"
echo "Set kernel '$ver' $PINNED_KERNEL_CONF. Use the 'refresh' command to update the ESPs."
}
unpin_kernel() {
rm -f "$PINNED_KERNEL_CONF"
echo "Removed $PINNED_KERNEL_CONF. Use the 'refresh' command to update the ESPs."
}
if [ -z "$1" ]; then
usage
exit 0
@ -460,6 +500,14 @@ case "$1" in
list_kernels
exit 0
;;
'pin')
pin_kernel "$2"
exit 0
;;
'unpin')
unpin_kernel "$2"
exit 0
;;
*)
warn "E: invalid 'kernel' subcommand '$cmd'."
warn ""

View File

@ -5,11 +5,13 @@ ESP_LIST="/etc/kernel/proxmox-boot-uuids"
ESPTYPE='c12a7328-f81f-11d2-ba4b-00a0c93ec93b'
MANUAL_KERNEL_LIST="/etc/kernel/pve-efiboot-manual-kernels"
PINNED_KERNEL_CONF="/etc/kernel/proxmox-boot-pin"
MOUNTROOT="${TMPDIR:-/var/tmp}/espmounts"
# relative to the ESP mountpoint
PMX_ESP_DIR="EFI/proxmox"
PMX_LOADER_CONF="loader/loader.conf"
GRUB_PIN_SNIPPET="/etc/default/grub.d/proxmox-kernel-pin.cfg"
# adapted from /etc/kernel/postinst.d/apt-auto-removal as present in
# debian's apt package:
@ -21,6 +23,7 @@ PMX_LOADER_CONF="loader/loader.conf"
# - the second-latest kernel version
# - the latest kernel version of each series (e.g. 4.13, 4.15, 5.0) by
# marking the meta-packages
# - the currently pinned kernel if any
kernel_keep_versions() {
eval "$(apt-config shell DPKG Dir::bin::dpkg/f)"
@ -56,6 +59,8 @@ kernel_keep_versions() {
manual_kernels="$(cat "$MANUAL_KERNEL_LIST")"
fi
pinned_kernel="$(get_first_line "$PINNED_KERNEL_CONF")"
kernels="$(cat <<-EOF
$running_version
$install_version
@ -63,6 +68,7 @@ kernel_keep_versions() {
$latest_2_versions
$series_metapackages
$oldseries_latest_kernel
$pinned_kernel
EOF
)"
@ -114,3 +120,34 @@ get_first_line() {
done < "${file}"
echo "$line"
}
set_grub_default() {
kver="$1"
if [ -z "${kver}" ]; then
rm -f "${GRUB_PIN_SNIPPET}"
else
# grub menu entry ids contain the internal root-device id (e.g. for zfs the GUID of
# the pool printed in hex) as this is independent of the ESP (or grub location)
# take it from /boot/grub/grub.cfg
root_devid=$(sed -rn "s/.*gnulinux-advanced-(.+)['] \{$/\1/p" \
/boot/grub/grub.cfg)
entry="gnulinux-advanced-${root_devid}>gnulinux-${kver}-advanced-${root_devid}"
echo "GRUB_DEFAULT=\"${entry}\"" > "${GRUB_PIN_SNIPPET}"
fi
}
set_systemd_boot_default() {
mountpoint="$1"
kver="$2"
if [ -z "${kver}" ]; then
entry="proxmox-*"
else
entry="proxmox-${kver}.conf"
fi
# replaces the current default entry, if one exists else append it at the end of the file
sed -ri "/^default /{h;s/ .*\$/ ${entry}/};\${x;/^$/{s//default ${entry}/;H};x}" \
"${mountpoint}/$PMX_LOADER_CONF"
}

View File

@ -90,9 +90,14 @@ update_esp_func() {
fi
warn "Copying and configuring kernels on ${path}"
copy_and_config_kernels "${mountpoint}"
pinned_kernel=$(get_first_line "${PINNED_KERNEL_CONF}")
if [ -d /sys/firmware/efi ]; then
set_systemd_boot_default "${mountpoint}" "${pinned_kernel}"
remove_old_kernels_efi "${mountpoint}"
else
set_grub_default "${pinned_kernel}"
remove_old_kernels_legacy "${mountpoint}"
mount --bind "${mountpoint}" "/boot"
update-grub