kexec-tools/dracut-kdump.sh

#!/bin/sh
#
# The main kdump routine in capture kernel
#

. /lib/dracut-lib.sh
. /lib/kdump-logger.sh
. /lib/kdump-lib-initramfs.sh

#initiate the kdump logger
if ! dlog_init; then
    echo "failed to initiate the kdump logger."
    exit 1
fi

KDUMP_PATH="/var/crash"
KDUMP_LOG_FILE="/run/initramfs/kexec-dmesg.log"
CORE_COLLECTOR=""
DEFAULT_CORE_COLLECTOR="makedumpfile -l --message-level 7 -d 31"
DMESG_COLLECTOR="/sbin/vmcore-dmesg"
FAILURE_ACTION="systemctl reboot -f"
DATEDIR=$(date +%Y-%m-%d-%T)
HOST_IP='127.0.0.1'
DUMP_INSTRUCTION=""
SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa"
DD_BLKSIZE=512
FINAL_ACTION="systemctl reboot -f"
KDUMP_PRE=""
KDUMP_POST=""
NEWROOT="/sysroot"
OPALCORE="/sys/firmware/opal/mpipl/core"
KDUMP_CONF_PARSED="/tmp/kdump.conf.$$"

# POSIX doesn't have pipefail, only apply when using bash
# shellcheck disable=SC3040
[ -n "$BASH" ] && set -o pipefail

DUMP_RETVAL=0

kdump_read_conf > $KDUMP_CONF_PARSED

get_kdump_confs()
{
    while read -r config_opt config_val; do
        # remove inline comments after the end of a directive.
        case "$config_opt" in
            path)
                KDUMP_PATH="$config_val"
            ;;
            core_collector)
                [ -n "$config_val" ] && CORE_COLLECTOR="$config_val"
            ;;
            sshkey)
                if [ -f "$config_val" ]; then
                    SSH_KEY_LOCATION=$config_val
                fi
            ;;
            kdump_pre)
                KDUMP_PRE="$config_val"
            ;;
            kdump_post)
                KDUMP_POST="$config_val"
            ;;
            fence_kdump_args)
                FENCE_KDUMP_ARGS="$config_val"
            ;;
            fence_kdump_nodes)
                FENCE_KDUMP_NODES="$config_val"
            ;;
            failure_action|default)
                case $config_val in
                    shell)
                        FAILURE_ACTION="kdump_emergency_shell"
                    ;;
                    reboot)
                        FAILURE_ACTION="systemctl reboot -f && exit"
                    ;;
                    halt)
                        FAILURE_ACTION="halt && exit"
                    ;;
                    poweroff)
                        FAILURE_ACTION="systemctl poweroff -f && exit"
                    ;;
                    dump_to_rootfs)
                        FAILURE_ACTION="dump_to_rootfs"
                    ;;
                esac
            ;;
            final_action)
                case $config_val in
                    reboot)
                        FINAL_ACTION="systemctl reboot -f"
                    ;;
                    halt)
                        FINAL_ACTION="halt"
                    ;;
                    poweroff)
                        FINAL_ACTION="systemctl poweroff -f"
                    ;;
                esac
            ;;
        esac
    done < "$KDUMP_CONF_PARSED"

    if [ -z "$CORE_COLLECTOR" ]; then
        CORE_COLLECTOR="$DEFAULT_CORE_COLLECTOR"
        if is_ssh_dump_target || is_raw_dump_target; then
            CORE_COLLECTOR="$CORE_COLLECTOR -F"
        fi
    fi
}

# store the kexec kernel log to a file.
save_log()
{
    dmesg -T > $KDUMP_LOG_FILE

    if command -v journalctl > /dev/null; then
        journalctl -ab >> $KDUMP_LOG_FILE
    fi
    chmod 600 $KDUMP_LOG_FILE
}

# $1: dump path, must be a mount point
dump_fs()
{
    ddebug "dump_fs _mp=$1"

    if ! is_mounted "$1"; then
        dinfo "dump path '$1' is not mounted, trying to mount..."
        if ! mount --target "$1"; then
            derror "failed to dump to '$1', it's not a mount point!"
            return 1
        fi
    fi

    # Remove -F in makedumpfile case. We don't want a flat format dump here.
    case $CORE_COLLECTOR in
        *makedumpfile* )
            CORE_COLLECTOR=$(echo "$CORE_COLLECTOR" | sed -e "s/-F//g")
            ;;
    esac

    _dump_fs_path=$(echo "$1/$KDUMP_PATH/$HOST_IP-$DATEDIR/" | tr -s /)
    dinfo "saving to $_dump_fs_path"

    # Only remount to read-write mode if the dump target is mounted read-only.
    _dump_mnt_op=$(get_mount_info OPTIONS target "$1" -f)
    case $_dump_mnt_op in
        ro* )
            dinfo "Remounting the dump target in rw mode."
            mount -o remount,rw "$1" || return 1
            ;;
    esac

    mkdir -p "$_dump_fs_path" || return 1

    save_vmcore_dmesg_fs ${DMESG_COLLECTOR} "$_dump_fs_path"
    save_opalcore_fs "$_dump_fs_path"

    dinfo "saving vmcore"
    $CORE_COLLECTOR /proc/vmcore "$_dump_fs_path/vmcore-incomplete"
    _dump_exitcode=$?
    if [ $_dump_exitcode -eq 0 ]; then
        mv "$_dump_fs_path/vmcore-incomplete" "$_dump_fs_path/vmcore"
        sync
        dinfo "saving vmcore complete"
    else
        derror "saving vmcore failed, exitcode:$_dump_exitcode"
    fi

    dinfo "saving the $KDUMP_LOG_FILE to $_dump_fs_path/"
    save_log
    mv "$KDUMP_LOG_FILE" "$_dump_fs_path/"
    if [ $_dump_exitcode -ne 0 ]; then
        return 1
    fi

    # improper kernel cmdline can cause the failure of echo, we can ignore this kind of failure
    return 0
}

# $1: dmesg collector
# $2: dump path
save_vmcore_dmesg_fs() {
    dinfo "saving vmcore-dmesg.txt to $2"
    if $1 /proc/vmcore > "$2/vmcore-dmesg-incomplete.txt"; then
        mv "$2/vmcore-dmesg-incomplete.txt" "$2/vmcore-dmesg.txt"
        chmod 600 "$2/vmcore-dmesg.txt"

        # Make sure file is on disk. There have been instances where later
        # saving vmcore failed and system rebooted without sync and there
        # was no vmcore-dmesg.txt available.
        sync
        dinfo "saving vmcore-dmesg.txt complete"
    else
        if [ -f "$2/vmcore-dmesg-incomplete.txt" ]; then
            chmod 600 "$2/vmcore-dmesg-incomplete.txt"
        fi
        derror "saving vmcore-dmesg.txt failed"
    fi
}

# $1: dump path
save_opalcore_fs() {
    if [ ! -f $OPALCORE ]; then
        # Check if we are on an old kernel that uses a different path
        if [ -f /sys/firmware/opal/core ]; then
            OPALCORE="/sys/firmware/opal/core"
        else
            return 0
        fi
    fi

    dinfo "saving opalcore:$OPALCORE to $1/opalcore"
    if ! cp $OPALCORE "$1/opalcore"; then
        derror "saving opalcore failed"
        return 1
    fi

    sync
    dinfo "saving opalcore complete"
    return 0
}

dump_to_rootfs()
{

    if [ "$(systemctl status dracut-initqueue | sed -n "s/^\s*Active: \(\S*\)\s.*$/\1/p")" = "inactive" ]; then
        dinfo "Trying to bring up initqueue for rootfs mount"
        systemctl start dracut-initqueue
    fi

    dinfo "Clean up dead systemd services"
    systemctl cancel
    dinfo "Waiting for rootfs mount, will timeout after 90 seconds"
    systemctl start --no-block sysroot.mount

    _loop=0
    while [ $_loop -lt 90 ] && ! is_mounted /sysroot; do
        sleep 1
        _loop=$((_loop + 1))
    done

    if ! is_mounted /sysroot; then
        derror "Failed to mount rootfs"
        return
    fi

    ddebug "NEWROOT=$NEWROOT"
    dump_fs $NEWROOT
}

kdump_emergency_shell()
{
    ddebug "Switching to kdump emergency shell..."

    [ -f /etc/profile ] && . /etc/profile
    export PS1='kdump:${PWD}# '

    . /lib/dracut-lib.sh
    if [ -f /dracut-state.sh ]; then
        . /dracut-state.sh 2>/dev/null
    fi

    source_conf /etc/conf.d

    type plymouth >/dev/null 2>&1 && plymouth quit

    source_hook "emergency"
    while read -r _tty rest; do
        (
        echo
        echo
        echo 'Entering kdump emergency mode.'
        echo 'Type "journalctl" to view system logs.'
        echo 'Type "rdsosreport" to generate a sosreport, you can then'
        echo 'save it elsewhere and attach it to a bug report.'
        echo
        echo
        ) > "/dev/$_tty"
    done < /proc/consoles
    sh -i -l
    /bin/rm -f -- /.console_lock
}

do_failure_action()
{
    dinfo "Executing failure action $FAILURE_ACTION"
    eval $FAILURE_ACTION
}

do_final_action()
{
    dinfo "Executing final action $FINAL_ACTION"
    eval $FINAL_ACTION
}

do_dump()
{
    eval $DUMP_INSTRUCTION
    _ret=$?

    if [ $_ret -ne 0 ]; then
        derror "saving vmcore failed"
    fi

    return $_ret
}

do_kdump_pre()
{
    if [ -n "$KDUMP_PRE" ]; then
        "$KDUMP_PRE"
        _ret=$?
        if [ $_ret -ne 0 ]; then
            derror "$KDUMP_PRE exited with $_ret status"
            return $_ret
        fi
    fi

    # if any script fails, it just raises warning and continues
    if [ -d /etc/kdump/pre.d ]; then
        for file in /etc/kdump/pre.d/*; do
            "$file"
            _ret=$?
            if [ $_ret -ne 0 ]; then
                derror "$file exited with $_ret status"
            fi
        done
    fi
    return 0
}

do_kdump_post()
{
    if [ -d /etc/kdump/post.d ]; then
        for file in /etc/kdump/post.d/*; do
            "$file" "$1"
            _ret=$?
            if [ $_ret -ne 0 ]; then
                derror "$file exited with $_ret status"
            fi
        done
    fi

    if [ -n "$KDUMP_POST" ]; then
        "$KDUMP_POST" "$1"
        _ret=$?
        if [ $_ret -ne 0 ]; then
            derror "$KDUMP_POST exited with $_ret status"
        fi
    fi
}

# $1: block target, eg. /dev/sda
dump_raw()
{
    [ -b "$1" ] || return 1

    dinfo "saving to raw disk $1"

    if ! echo "$CORE_COLLECTOR" | grep -q makedumpfile; then
        _src_size=$(stat --format %s /proc/vmcore)
        _src_size_mb=$((_src_size / 1048576))
        /kdumpscripts/monitor_dd_progress $_src_size_mb &
    fi

    dinfo "saving vmcore"
    $CORE_COLLECTOR /proc/vmcore | dd of="$1" bs=$DD_BLKSIZE >> /tmp/dd_progress_file 2>&1 || return 1
    sync

    dinfo "saving vmcore complete"
    return 0
}

# $1: ssh key file
# $2: ssh address in <user>@<host> format
dump_ssh()
{
    _ret=0
    _ssh_opt="-i $1 -o BatchMode=yes -o StrictHostKeyChecking=yes"
    _ssh_dir="$KDUMP_PATH/$HOST_IP-$DATEDIR"
    if is_ipv6_address "$2"; then
        _scp_address=${2%@*}@"[${2#*@}]"
    else
        _scp_address=$2
    fi

    dinfo "saving to $2:$_ssh_dir"

    cat /var/lib/random-seed > /dev/urandom
    ssh -q $_ssh_opt "$2" mkdir -p "$_ssh_dir" || return 1

    save_vmcore_dmesg_ssh "$DMESG_COLLECTOR" "$_ssh_dir" "$_ssh_opt" "$2"
    dinfo "saving vmcore"

    save_opalcore_ssh "$_ssh_dir" "$_ssh_opt" "$2" "$_scp_address"

    if [ "${CORE_COLLECTOR%%[[:blank:]]*}" = "scp" ]; then
        scp -q $_ssh_opt /proc/vmcore "$_scp_address:$_ssh_dir/vmcore-incomplete"
        _ret=$?
        _vmcore="vmcore"
    else
        $CORE_COLLECTOR /proc/vmcore | ssh $_ssh_opt "$2" "umask 0077 && dd bs=512 of='$_ssh_dir/vmcore-incomplete'"
        _ret=$?
        _vmcore="vmcore.flat"
    fi

    if [ $_ret -eq 0 ]; then
        ssh $_ssh_opt "$2" "mv '$_ssh_dir/vmcore-incomplete' '$_ssh_dir/$_vmcore'"
        _ret=$?
        if [ $_ret -ne 0 ]; then
            derror "moving vmcore failed, exitcode:$_ret"
        else
            dinfo "saving vmcore complete"
        fi
    else
        derror "saving vmcore failed, exitcode:$_ret"
    fi

    dinfo "saving the $KDUMP_LOG_FILE to $2:$_ssh_dir/"
    save_log
    if ! scp -q $_ssh_opt $KDUMP_LOG_FILE "$_scp_address:$_ssh_dir/"; then
        derror "saving log file failed, _exitcode:$_ret"
    fi

    return $_ret
}

# $1: dump path
# $2: ssh opts
# $3: ssh address in <user>@<host> format
# $4: scp address, similar with ssh address but IPv6 addresses are quoted
save_opalcore_ssh() {
    if [ ! -f $OPALCORE ]; then
        # Check if we are on an old kernel that uses a different path
        if [ -f /sys/firmware/opal/core ]; then
            OPALCORE="/sys/firmware/opal/core"
        else
            return 0
        fi
    fi

    dinfo "saving opalcore:$OPALCORE to $3:$1"

    if ! scp $2 $OPALCORE "$4:$1/opalcore-incomplete"; then
        derror "saving opalcore failed"
        return 1
    fi

    ssh $2 "$3" mv "$1/opalcore-incomplete" "$1/opalcore"
    dinfo "saving opalcore complete"
    return 0
}

# $1: dmesg collector
# $2: dump path
# $3: ssh opts
# $4: ssh address in <user>@<host> format
save_vmcore_dmesg_ssh() {
    dinfo "saving vmcore-dmesg.txt to $4:$2"
    if $1 /proc/vmcore | ssh $3 "$4" "umask 0077 && dd of='$2/vmcore-dmesg-incomplete.txt'"; then
        ssh -q $3 "$4" mv "$2/vmcore-dmesg-incomplete.txt" "$2/vmcore-dmesg.txt"
        dinfo "saving vmcore-dmesg.txt complete"
    else
        derror "saving vmcore-dmesg.txt failed"
    fi
}

get_host_ip()
{
    if is_nfs_dump_target || is_ssh_dump_target
    then
        kdumpnic=$(getarg kdumpnic=)
        if [ -z "$kdumpnic" ]; then
            derror "failed to get kdumpnic!"
            return 1
        fi
        if ! kdumphost=$(ip addr show dev "$kdumpnic" | grep '[ ]*inet'); then
            derror "wrong kdumpnic: $kdumpnic"
            return 1
        fi
        kdumphost=$(echo "$kdumphost" | head -n 1 | awk '{print $2}')
        kdumphost="${kdumphost%%/*}"
        if [ -z "$kdumphost" ]; then
            derror "wrong kdumpnic: $kdumpnic"
            return 1
        fi
        HOST_IP=$kdumphost
    fi
    return 0
}

read_kdump_confs()
{
    if [ ! -f "$KDUMP_CONFIG_FILE" ]; then
        derror "$KDUMP_CONFIG_FILE not found"
        return
    fi

    get_kdump_confs

    # rescan for add code for dump target
    while read -r config_opt config_val;
    do
        # remove inline comments after the end of a directive.
        case "$config_opt" in
        dracut_args)
            config_val=$(get_dracut_args_target "$config_val")
            if [ -n "$config_val" ]; then
                config_val=$(get_mntpoint_from_target "$config_val")
                DUMP_INSTRUCTION="dump_fs $config_val"
            fi
            ;;
        ext[234]|xfs|btrfs|minix|nfs)
            config_val=$(get_mntpoint_from_target "$config_val")
            DUMP_INSTRUCTION="dump_fs $config_val"
            ;;
        raw)
            DUMP_INSTRUCTION="dump_raw $config_val"
            ;;
        ssh)
            DUMP_INSTRUCTION="dump_ssh $SSH_KEY_LOCATION $config_val"
            ;;
        esac
    done < "$KDUMP_CONF_PARSED"
}

fence_kdump_notify()
{
    if [ -n "$FENCE_KDUMP_NODES" ]; then
        # shellcheck disable=SC2086
        $FENCE_KDUMP_SEND $FENCE_KDUMP_ARGS $FENCE_KDUMP_NODES &
    fi
}

if [ "$1" = "--error-handler" ]; then
    get_kdump_confs
    do_failure_action
    do_final_action

    exit $?
fi

# continue here only if we have to save dump.
if [ -f /etc/fadump.initramfs ] && [ ! -f /proc/device-tree/rtas/ibm,kernel-dump ] && [ ! -f /proc/device-tree/ibm,opal/dump/mpipl-boot ]; then
    exit 0
fi

read_kdump_confs
fence_kdump_notify

if ! get_host_ip; then
    derror "get_host_ip exited with non-zero status!"
    exit 1
fi

if [ -z "$DUMP_INSTRUCTION" ]; then
    DUMP_INSTRUCTION="dump_fs $NEWROOT"
fi

if ! do_kdump_pre; then
    derror "kdump_pre script exited with non-zero status!"
    do_final_action
    # During systemd service to reboot the machine, stop this shell script running
    exit 1
fi
make_trace_mem "kdump saving vmcore" '1:shortmem' '2+:mem' '3+:slab'
do_dump
DUMP_RETVAL=$?

if ! do_kdump_post $DUMP_RETVAL; then
    derror "kdump_post script exited with non-zero status!"
fi

if [ $DUMP_RETVAL -ne 0 ]; then
    exit 1
fi

do_final_action