kexec-tools/mkdumprd
Kairui Song ca01cbdfd5 mkdumprd: generate usable kdump initramfs even target is not mounted
Currently kexec-tools always depend on dump target to be mounted, which
caused some inconvenience for setup.

So for user configured target, allow kdump to start and build initramfs
even if target is not mounted.

When a mounted user configured target is used, the behavior is not
changed.

When a unmounted user configured target is used, mkdumprd will look for
corresponding mount info in fstab, and a entry with noauto option is
founded, mkdumprd will try to mount it inplace with optoins specified
in fstab and do basic checks on the device, then umount it.

If there is no fstab entry, mkdumprd will try to mount it in temporary
path with defaults option, do same basic check and umount it.

If there is a fstab entry but "noauto" option is not used, then there
must be some reason that the target device is not mounted, mkdumprd will
error out.

When path based target is used, there is no behavior change.

Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
2020-05-22 16:14:07 +08:00

490 lines
13 KiB
Bash

#!/bin/bash --norc
# New mkdumprd
#
# Copyright 2011 Red Hat, Inc.
#
# Written by Cong Wang <amwang@redhat.com>
#
[[ $dracutbasedir ]] || dracutbasedir=/usr/lib/dracut
. $dracutbasedir/dracut-functions.sh
. /lib/kdump/kdump-lib.sh
export IN_KDUMP=1
conf_file="/etc/kdump.conf"
SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa"
SAVE_PATH=$(get_save_path)
OVERRIDE_RESETTABLE=0
extra_modules=""
dracut_args="--quiet --hostonly --hostonly-cmdline --hostonly-i18n --hostonly-mode strict -o \"plymouth dash resume ifcfg earlykdump\""
readonly MKDUMPRD_TMPDIR="$(mktemp -d -t mkdumprd.XXXXXX)"
[ -d "$MKDUMPRD_TMPDIR" ] || perror_exit "dracut: mktemp -p -d -t dracut.XXXXXX failed."
readonly MKDUMPRD_TMPMNT="$MKDUMPRD_TMPDIR/target"
trap '
ret=$?;
is_mounted $MKDUMPRD_TMPMNT && umount -f $MKDUMPRD_TMPMNT;
[[ -d $MKDUMPRD_TMPDIR ]] && rm --one-file-system -rf -- "$MKDUMPRD_TMPDIR";
exit $ret;
' EXIT
# clean up after ourselves no matter how we die.
trap 'exit 1;' SIGINT
is_wdt_addition_needed() {
local active
is_wdt_mod_omitted
[[ $? -eq 0 ]] && return 1
[[ -d /sys/class/watchdog/ ]] || return 1
for dir in /sys/class/watchdog/*; do
[[ -f "$dir/state" ]] || continue
active=$(< "$dir/state")
[[ "$active" = "active" ]] && return 0
done
return 1
}
add_dracut_arg() {
dracut_args="$dracut_args $@"
}
add_dracut_module() {
add_dracut_arg "--add" "\"$1\""
}
add_dracut_mount() {
add_dracut_arg "--mount" "\"$1\""
}
add_dracut_sshkey() {
add_dracut_arg "--sshkey" "\"$1\""
}
# caller should ensure $1 is valid and mounted in 1st kernel
to_mount() {
local _target=$1 _fstype=$2 _options=$3 _new_mntpoint _mntopts _pdev
_new_mntpoint=$(get_kdump_mntpoint_from_target $_target)
_fstype="${_fstype:-$(get_fs_type_from_target $_target)}"
_options="${_options:-$(get_mntopt_from_target $_options)}"
_options="${_options:-defaults}"
if [[ "$_fstype" == "nfs"* ]]; then
_options=$(echo $_options | sed 's/,addr=[^,]*//')
_options=$(echo $_options | sed 's/,proto=[^,]*//')
_options=$(echo $_options | sed 's/,clientaddr=[^,]*//')
fi
# mount fs target as rw in 2nd kernel
_options=$(echo $_options | sed 's/\(^\|,\)ro\($\|,\)/\1rw\2/g')
# with 'noauto' in fstab nfs and non-root disk mount will fail in 2nd
# kernel, filter it out here.
_options=$(echo $_options | sed 's/\(^\|,\)noauto\($\|,\)/\1/g')
# drop nofail or nobootwait
_options=$(echo $_options | sed 's/\(^\|,\)nofail\($\|,\)/\1/g')
_options=$(echo $_options | sed 's/\(^\|,\)nobootwait\($\|,\)/\1/g')
# use both nofail and x-systemd.before to ensure systemd will try best to
# mount it before kdump starts, this is an attempt to improve robustness
_options="$_options,nofail,x-systemd.before=initrd-fs.target"
_mntopts="$_new_mntpoint $_fstype $_options"
# for non-nfs _target converting to use udev persistent name
if [ -b "$_target" ]; then
_pdev="$(get_persistent_dev $_target)"
if [ -z "$_pdev" ]; then
return 1
fi
else
_pdev=$_target
fi
echo "$_pdev $_mntopts"
}
#Function: get_ssh_size
#$1=dump target
#called from while loop and shouldn't read from stdin, so we're using "ssh -n"
get_ssh_size() {
local _opt _out _size
_opt="-i $SSH_KEY_LOCATION -o BatchMode=yes -o StrictHostKeyChecking=yes"
_out=$(ssh -q -n $_opt $1 "df -P $SAVE_PATH")
[ $? -ne 0 ] && {
perror_exit "checking remote ssh server available size failed."
}
#ssh output removed the line break, so print field NF-2
_size=$(echo -n $_out| awk '{avail=NF-2; print $avail}')
echo -n $_size
}
#mkdir if save path does not exist on ssh dump target
#$1=ssh dump target
#caller should ensure write permission on $1:$SAVE_PATH
#called from while loop and shouldn't read from stdin, so we're using "ssh -n"
mkdir_save_path_ssh()
{
local _opt _dir
_opt="-i $SSH_KEY_LOCATION -o BatchMode=yes -o StrictHostKeyChecking=yes"
ssh -qn $_opt $1 mkdir -p $SAVE_PATH 2>&1 > /dev/null
_ret=$?
if [ $_ret -ne 0 ]; then
perror_exit "mkdir failed on $1:$SAVE_PATH"
fi
#check whether user has write permission on $1:$SAVE_PATH
_dir=$(ssh -qn $_opt $1 mktemp -dqp $SAVE_PATH 2>/dev/null)
_ret=$?
if [ $_ret -ne 0 ]; then
perror_exit "Could not create temporary directory on $1:$SAVE_PATH. Make sure user has write permission on destination"
fi
ssh -qn $_opt $1 rmdir $_dir
return 0
}
#Function: get_fs_size
#$1=dump target
get_fs_size() {
local _mnt=$(get_mntpoint_from_target $1)
echo -n $(df -P "${_mnt}/$SAVE_PATH"|tail -1|awk '{print $4}')
}
#Function: get_raw_size
#$1=dump target
get_raw_size() {
echo -n $(fdisk -s "$1")
}
#Function: check_size
#$1: dump type string ('raw', 'fs', 'ssh')
#$2: dump target
check_size() {
local avail memtotal
memtotal=$(awk '/MemTotal/{print $2}' /proc/meminfo)
case "$1" in
raw)
avail=$(get_raw_size "$2")
;;
ssh)
avail=$(get_ssh_size "$2")
;;
fs)
avail=$(get_fs_size "$2")
;;
*)
return
esac
if [ $? -ne 0 ]; then
perror_exit "Check dump target size failed"
fi
if [ $avail -lt $memtotal ]; then
echo "Warning: There might not be enough space to save a vmcore."
echo " The size of $2 should be greater than $memtotal kilo bytes."
fi
}
check_save_path_fs()
{
local _path=$1
if [ ! -d $_path ]; then
perror_exit "Dump path $_path does not exist."
fi
}
check_user_configured_target()
{
local _target=$1 _cfg_fs_type=$2 _mounted
local _mnt=$(get_mntpoint_from_target $_target)
local _opt=$(get_mntopt_from_target $_target)
local _fstype=$(get_fs_type_from_target $_target)
if [ -n "$_fstype" ]; then
# In case of nfs4, nfs should be used instead, nfs* options is deprecated in kdump.conf
[[ $_fstype = "nfs"* ]] && _fstype=nfs
if [ -n "$_cfg_fs_type" ] && [ "$_fstype" != "$_cfg_fs_type" ]; then
perror_exit "\"$_target\" have a wrong type config \"$_cfg_fs_type\", expected \"$_fstype\""
fi
else
_fstype="$_cfg_fs_type"
_fstype="$_cfg_fs_type"
fi
# For noauto mount, mount it inplace with default value.
# Else use the temporary target directory
if [ -n "$_mnt" ]; then
if ! is_mounted "$_mnt"; then
if [[ $_opt = *",noauto"* ]]; then
mount $_mnt
[ $? -ne 0 ] && perror_exit "Failed to mount $_target on $_mnt for kdump preflight check."
_mounted=$_mnt
else
perror_exit "$_target is configured in fstab but not mounted, please check its usability."
fi
fi
else
_mnt=$MKDUMPRD_TMPMNT
mkdir -p $_mnt
mount $_target $_mnt -t $_fstype -o defaults
[ $? -ne 0 ] && perror_exit "Failed to mount $_target for kdump preflight check."
_mounted=$_mnt
fi
# For user configured target, use $SAVE_PATH as the dump path within the target
if [ ! -d "$_mnt/$SAVE_PATH" ]; then
perror_exit "Dump path \"$SAVE_PATH\" does not exist in dump target \"$_target\""
fi
check_size fs "$_target"
# Unmount it early, if function is interrupted and didn't reach here, the shell trap will clear it up anyway
if [ -n "$_mounted" ]; then
umount -f -- $_mounted
fi
}
# $1: core_collector config value
verify_core_collector() {
local _cmd="${1%% *}"
local _params="${1#* }"
if [ "$_cmd" != "makedumpfile" ]; then
if is_raw_dump_target; then
echo "Warning: specifying a non-makedumpfile core collector, you will have to recover the vmcore manually."
fi
return
fi
if is_ssh_dump_target || is_raw_dump_target; then
if ! strstr "$_params" "-F"; then
perror_exit "The specified dump target needs makedumpfile \"-F\" option."
fi
_params="$_params vmcore"
else
_params="$_params vmcore dumpfile"
fi
if ! $_cmd --check-params $_params; then
perror_exit "makedumpfile parameter check failed."
fi
}
add_mount() {
local _mnt=$(to_mount $@)
if [ $? -ne 0 ]; then
exit 1
fi
add_dracut_mount "$_mnt"
}
#handle the case user does not specify the dump target explicitly
handle_default_dump_target()
{
local _target
local _mntpoint
is_user_configured_dump_target && return
check_save_path_fs $SAVE_PATH
_save_path=$(get_bind_mount_source $SAVE_PATH)
_target=$(get_target_from_path $_save_path)
_mntpoint=$(get_mntpoint_from_target $_target)
SAVE_PATH=${_save_path##"$_mntpoint"}
add_mount "$_target"
check_size fs $_target
}
get_override_resettable()
{
local override_resettable
override_resettable=$(grep "^override_resettable" $conf_file)
if [ -n "$override_resettable" ]; then
OVERRIDE_RESETTABLE=$(echo $override_resettable | cut -d' ' -f2)
if [ "$OVERRIDE_RESETTABLE" != "0" ] && [ "$OVERRIDE_RESETTABLE" != "1" ];then
perror_exit "override_resettable value $OVERRIDE_RESETTABLE is invalid"
fi
fi
}
# $1: function name
for_each_block_target()
{
local dev majmin
for dev in $(get_kdump_targets); do
[ -b "$dev" ] || continue
majmin=$(get_maj_min $dev)
check_block_and_slaves $1 $majmin && return 1
done
return 0
}
#judge if a specific device with $1 is unresettable
#return false if unresettable.
is_unresettable()
{
local path="/sys/$(udevadm info --query=all --path=/sys/dev/block/$1 | awk '/^P:/ {print $2}' | sed -e 's/\(cciss[0-9]\+\/\).*/\1/g' -e 's/\/block\/.*$//')/resettable"
local resettable=1
if [ -f "$path" ]
then
resettable="$(cat $path)"
[ $resettable -eq 0 -a "$OVERRIDE_RESETTABLE" -eq 0 ] && {
local device=$(udevadm info --query=all --path=/sys/dev/block/$1 | awk -F= '/DEVNAME/{print $2}')
echo "Error: Can not save vmcore because device $device is unresettable"
return 0
}
fi
return 1
}
#check if machine is resettable.
#return true if resettable
check_resettable()
{
local _ret _target
get_override_resettable
for_each_block_target is_unresettable
_ret=$?
[ $_ret -eq 0 ] && return
return 1
}
# $1: maj:min
is_crypt()
{
local majmin=$1 dev line ID_FS_TYPE=""
line=$(udevadm info --query=property --path=/sys/dev/block/$majmin \
| grep "^ID_FS_TYPE")
eval "$line"
[[ "$ID_FS_TYPE" = "crypto_LUKS" ]] && {
dev=$(udevadm info --query=all --path=/sys/dev/block/$majmin | awk -F= '/DEVNAME/{print $2}')
echo "Device $dev is encrypted."
return 0
}
return 1
}
check_crypt()
{
local _ret _target
for_each_block_target is_crypt
_ret=$?
[ $_ret -eq 0 ] && return
return 1
}
if ! check_resettable; then
exit 1
fi
if ! check_crypt; then
echo "Warning: Encrypted device is in dump path. User will prompted for password during second kernel boot."
fi
# firstly get right SSH_KEY_LOCATION
keyfile=$(awk '/^sshkey/ {print $2}' $conf_file)
if [ -f "$keyfile" ]; then
# canonicalize the path
SSH_KEY_LOCATION=$(/usr/bin/readlink -m $keyfile)
fi
if [ "$(uname -m)" = "s390x" ]; then
add_dracut_module "znet"
fi
if is_wdt_addition_needed; then
add_dracut_arg "-a" "watchdog"
fi
while read config_opt config_val;
do
# remove inline comments after the end of a directive.
case "$config_opt" in
extra_modules)
extra_modules="$extra_modules $config_val"
;;
ext[234]|xfs|btrfs|minix|nfs)
check_user_configured_target "$config_val" "$config_opt"
add_mount "$config_val" "$config_opt"
;;
raw)
# checking raw disk writable
dd if=$config_val count=1 of=/dev/null > /dev/null 2>&1 || {
perror_exit "Bad raw disk $config_val"
}
_praw=$(persistent_policy="by-id" get_persistent_dev $config_val)
if [ -z "$_praw" ]; then
exit 1
fi
add_dracut_arg "--device" "$_praw"
check_size raw $config_val
;;
ssh)
if strstr "$config_val" "@";
then
mkdir_save_path_ssh $config_val
check_size ssh $config_val
add_dracut_module "ssh-client"
add_dracut_sshkey "$SSH_KEY_LOCATION"
else
perror_exit "Bad ssh dump target $config_val"
fi
;;
core_collector)
verify_core_collector "$config_val"
;;
dracut_args)
add_dracut_arg $config_val
;;
*)
;;
esac
done <<< "$(read_strip_comments $conf_file)"
handle_default_dump_target
if [ -n "$extra_modules" ]
then
add_dracut_arg "--add-drivers" "$extra_modules"
fi
if ! is_fadump_capable; then
# The 2nd rootfs mount stays behind the normal dump target mount,
# so it doesn't affect the logic of check_dump_fs_modified().
is_dump_to_rootfs && add_mount "$(to_dev_name $(get_root_fs_device))"
add_dracut_arg "--no-hostonly-default-device"
fi
echo "$dracut_args $@" | xargs dracut
_rc=$?
sync
exit $_rc