kexec-tools/mkdumprd

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2006-07-20 03:36:18 +00:00
#!/bin/bash --norc
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# New mkdumprd
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#
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# Copyright 2011 Red Hat, Inc.
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#
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# Written by Cong Wang <amwang@redhat.com>
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#
. /lib/kdump/kdump-lib.sh
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export IN_KDUMP=1
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conf_file="/etc/kdump.conf"
SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa"
SAVE_PATH=$(grep ^path $conf_file| cut -d' ' -f2)
[ -z "$SAVE_PATH" ] && SAVE_PATH=$DEFAULT_PATH
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extra_modules=""
dracut_args=("--hostonly" "-o" "plymouth dash resume")
OVERRIDE_RESETTABLE=0
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perror_exit() {
echo $@ >&2
exit 1
}
perror() {
echo $@ >&2
}
get_persistent_dev() {
local i _tmp _dev
_dev=$(udevadm info --query=name --name="$1" 2>/dev/null)
[ -z "$_dev" ] && {
perror_exit "Kernel dev name of $1 is not found."
}
for i in /dev/mapper/* /dev/disk/by-uuid/* /dev/disk/by-id/*; do
_tmp=$(udevadm info --query=name --name="$i" 2>/dev/null)
if [ "$_tmp" = "$_dev" ]; then
echo $i
return
fi
done
perror "WARNING: Persistent device name of $1 not found. Using $1 as dump target name"
echo $1
}
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add_dracut_arg() {
add dracut_args option to kdump.conf mkdumprd call dracut to rebuilding kdump initrd, sometimes passing extra dracut args is helpful. For example user can enable debug output with --debug, --printsize to print roughly increased initramfs size by each module, --omit-drivers to omit kernel modules, etc. This patch enables dracut_args option for passing extra args to dracut. Also it modifies add_dracut_arg() to treat a string with-in quote as single string because for dracut options which has its own args, the args need to be quoted and space seperated. If add_dracut_arg() gets an string read from kdump.conf and if that string contains double quotes, then while converting to positional parameters those double quotes are not interpreted. Hence if /etc/kdump.conf contains following. dracut_args --add-drivers "driver1 driver2" then add_dracut_args() sees following positional parameters $1= --add-drivers $2= "driver1 $3= driver2" Notice, double quotes have been ignored and parameters have been broken based on white space. Modify add_dracut_arg() to look for parameters starting with " and if one is found, it tries to merge all the next parameters till one is found with ending double quote. Hence effectively simulating following behavior. $1= --add-drivers $2= "driver1 driver2" [v1->v2]: address quoted substring in dracut_args, also handle the leading and ending spaces in substring. [v2->v3]: fix dracut arguments seperator in kdump.conf. [v3->v4]: improve changelog, thanks vivek. [v4->v5]: make the manpage more verbose [vivek]. Tested with below dracut_args test cases: 1. dracut_args --add-drivers "pcspkr virtio_net" --omit-drivers "sdhci-pci hid-logitech-dj e1000" 2. dracut_args --add-drivers " pcspkr virtio_net " --omit-drivers "sdhci-pci hid-logitech-dj e1000" Signed-off-by: Dave Young <dyoung@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
2013-04-15 02:12:05 +00:00
local arg qarg is_quoted=0
while [ $# -gt 0 ];
do
add dracut_args option to kdump.conf mkdumprd call dracut to rebuilding kdump initrd, sometimes passing extra dracut args is helpful. For example user can enable debug output with --debug, --printsize to print roughly increased initramfs size by each module, --omit-drivers to omit kernel modules, etc. This patch enables dracut_args option for passing extra args to dracut. Also it modifies add_dracut_arg() to treat a string with-in quote as single string because for dracut options which has its own args, the args need to be quoted and space seperated. If add_dracut_arg() gets an string read from kdump.conf and if that string contains double quotes, then while converting to positional parameters those double quotes are not interpreted. Hence if /etc/kdump.conf contains following. dracut_args --add-drivers "driver1 driver2" then add_dracut_args() sees following positional parameters $1= --add-drivers $2= "driver1 $3= driver2" Notice, double quotes have been ignored and parameters have been broken based on white space. Modify add_dracut_arg() to look for parameters starting with " and if one is found, it tries to merge all the next parameters till one is found with ending double quote. Hence effectively simulating following behavior. $1= --add-drivers $2= "driver1 driver2" [v1->v2]: address quoted substring in dracut_args, also handle the leading and ending spaces in substring. [v2->v3]: fix dracut arguments seperator in kdump.conf. [v3->v4]: improve changelog, thanks vivek. [v4->v5]: make the manpage more verbose [vivek]. Tested with below dracut_args test cases: 1. dracut_args --add-drivers "pcspkr virtio_net" --omit-drivers "sdhci-pci hid-logitech-dj e1000" 2. dracut_args --add-drivers " pcspkr virtio_net " --omit-drivers "sdhci-pci hid-logitech-dj e1000" Signed-off-by: Dave Young <dyoung@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
2013-04-15 02:12:05 +00:00
arg="${1//\'/\"}"
#Handle quoted substring properly for passing it to dracut_args array.
if [ $is_quoted -eq 0 ]; then
if [[ "$arg" == "\"" ]] || [[ $arg != ${arg#\"} ]]; then
is_quoted=1
arg=${arg#\"}
fi
fi
if [ $is_quoted -eq 1 ]; then
qarg="$qarg $arg"
if [[ "$arg" == "\"" ]] || [[ $arg != ${arg%\"} ]]; then
is_quoted=0
arg=${qarg%\"}
qarg=""
else
shift
continue
fi
fi
dracut_args+=("$arg")
shift
done
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}
add_dracut_module() {
add_dracut_arg "--add" "$1"
}
add_dracut_mount() {
add_dracut_arg "--mount" "$1"
}
add_dracut_sshkey() {
add_dracut_arg "--sshkey" "$1"
}
# Generic substring function. If $2 is in $1, return 0.
strstr() { [[ $1 =~ $2 ]]; }
target_is_root() {
local _t
_t=$(findmnt -k -n -r -o TARGET $1|sort|head -1)
[ "$_t" = "/" ]
}
# caller should ensure $1 is valid and mounted in 1st kernel
to_mount() {
local _dev=$1 _source _target _fstype _options _mntopts _pdev
_source=$(findmnt -k -f -n -r -o SOURCE $_dev)
_target=$(findmnt -k -f -n -r -o TARGET $_dev)
# mount under /sysroot in 2nd kernel, and we umount -R /sysroot before exit
_target="/sysroot$_target"
_fstype=$(findmnt -k -f -n -r -o FSTYPE $_dev)
_options=$(findmnt --fstab -f -n -r -o OPTIONS $_dev)
[ -z "$_options" ] && _options=$(findmnt -k -f -n -r -o OPTIONS $_dev)
_options=${_options/#ro/rw} #mount fs target as rw in 2nd kernel
mkdumprd: append "x-initrd.mount" to the mount options. Now when mount in /etc/fstab fails, systemd would not consider it as critical and it would continue to boot. In fact, emergency service is triggered, but not in a isolation mode, and it results in the emergency service getting shutdown at some point later of the boot process. We need isolation otherwise we won't see any emergency service. That is because in kdump initramfs, mount units specified in /etc/fstab are required by "local-fs.target". When any of these mounts fails, local-fs.target fails. For kdump initramfs, we need to isolate to emergency service on any of the mount failure, that said, every service should be stopped and onlu emergency service would run. But local-fs.target won't trigger that on its failure. That means in case of mount failure, local-fs.target also enters failure state, but all the service will continue without any interruption. After digging looking into source code of systemd-fstab-generator. I find "x-initrd.mount" using in initramfs mount, will make the mount units required by "initrd-root-fs.target" rather than it's used to be "local-fs.target". "initrd-root-fs.target" is suitable to us because if it fails, it will isolate to emergency service. That means in case of any mount failure, the emergeny service will start and everything else will stop. We want this effect because we need to take kdump fail-safe action when there's a mount failure. From systemd unit point of view, "initrd-root-fs.target" has OnFailureIsolate=yes, but "local-fs.target" doesn't. From systemd.unit(5): OnFailureIsolate= Takes a boolean argument. If true, the unit listed in OnFailure= will be enqueued in isolation mode, i.e. all units that are not its dependency will be stopped. If this is set, only a single unit may be listed in OnFailure=. Defaults to false. NOTE: Harald who contributed "x-initrd.mount" in systemd, confirmed that this feature will stay. Signed-off-by: WANG Chao <chaowang@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-06-16 08:57:21 +00:00
# "x-initrd.mount" mount failure will trigger isolate emergency service
# W/o this, systemd won't isolate, thus we won't get to emergency.
# This is not applicable to remote fs mount, because if we use
# "x-initrd.mount", remote mount will become required by
# "initrd-root-fs.target", instead of "remote-fs.target". That's how it is
# handled within systemd internal. We need remote mount to be required
# "remote-fs.target", because we need to bring up network before any remote
# mount and "remote-fs.target" can be a checkpoint of that.
# If remote mount fails, dracut-initqueue will still start and once
# dracut-initqueue finishes, kdump service will start. Because remote mount
# failed, kdump service will fail and it will lead to kdump error handler.
if ! is_nfs_dump_target; then
_options="$_options,x-initrd.mount"
fi
_mntopts="$_target $_fstype $_options"
#for non-nfs _dev converting to use udev persistent name
if [ -b "$_source" ]; then
_pdev="$(get_persistent_dev $_source)"
if [ $? -ne 0 ]; then
return 1
fi
else
_pdev=$_dev
fi
echo "$_pdev $_mntopts"
}
to_mount_point() {
echo $(findmnt -k -f -n -r -o TARGET $1)
}
is_readonly_mount() {
local _mnt
_mnt=$(findmnt -k -f -n -r -o OPTIONS $1)
#fs/proc_namespace.c: show_mountinfo():
#seq_puts(m, mnt->mnt_flags & MNT_READONLY ? " ro" : " rw");
[[ "$_mnt" =~ ^ro ]]
}
#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 $DUMP_TARGET:$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 $DUMP_TARGET:$SAVE_PATH"
fi
#check whether user has write permission on $SAVE_PATH/$DUMP_TARGET
_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 $DUMP_TARGET:$SAVE_PATH. Make sure user has write permission on destination"
fi
ssh -qn $_opt $1 rmdir $_dir
return 0
}
#Function: get_fs_size
#$1=dump target
get_fs_size() {
local _mnt=$(to_mount_point $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
}
# $1: core_collector config value
verify_core_collector() {
if grep -q "^raw" $conf_file && [ "${1%% *}" != "makedumpfile" ]; then
echo "Warning: specifying a non-makedumpfile core collector, you will have to recover the vmcore manually."
fi
if is_ssh_dump_target || is_raw_dump_target; then
if [ "${1%% *}" = "makedumpfile" ]; then
! strstr "$1" "-F" && {
perror_exit "The specified dump target needs makedumpfile \"-F\" option."
}
fi
fi
}
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add_mount() {
if ! target_is_root "$1"; then
local _mnt=$(to_mount "$1")
if [ $? -ne 0 ]; then
exit 1
fi
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add_dracut_mount "$_mnt"
fi
}
# get_maj_min <device>
# Prints the major and minor of a device node.
# Example:
# $ get_maj_min /dev/sda2
# 8:2
get_maj_min() {
local _dev
_dev=$(stat -L -c '$((0x%t)):$((0x%T))' "$1" 2>/dev/null)
_dev=$(eval "echo $_dev")
echo $_dev
}
# ugly workaround for the lvm design
# There is no volume group device,
# so, there are no slave devices for volume groups.
# Logical volumes only have the slave devices they really live on,
# but you cannot create the logical volume without the volume group.
# And the volume group might be bigger than the devices the LV needs.
check_vol_slaves() {
local _lv _vg _pv
for i in /dev/mapper/*; do
_lv=$(get_maj_min $i)
if [[ $_lv = $2 ]]; then
_vg=$(lvm lvs --noheadings -o vg_name $i 2>/dev/null)
# strip space
_vg=$(echo $_vg)
if [[ $_vg ]]; then
for _pv in $(lvm vgs --noheadings -o pv_name "$_vg" 2>/dev/null)
do
check_block_and_slaves $1 $(get_maj_min $_pv) && return 0
done
fi
fi
done
return 1
}
# Walk all the slave relationships for a given block device.
# Stop when our helper function returns success
# $1 = function to call on every found block device
# $2 = block device in major:minor format
check_block_and_slaves() {
local _x
[[ -b /dev/block/$2 ]] || return 1 # Not a block device? So sorry.
"$1" $2 && return
check_vol_slaves "$@" && return 0
if [[ -f /sys/dev/block/$2/../dev ]]; then
check_block_and_slaves $1 $(cat "/sys/dev/block/$2/../dev") && return 0
fi
[[ -d /sys/dev/block/$2/slaves ]] || return 1
for _x in /sys/dev/block/$2/slaves/*/dev; do
[[ -f $_x ]] || continue
check_block_and_slaves $1 $(cat "$_x") && return 0
done
return 1
}
to_dev_name() {
local dev="${1//\"/}"
case "$dev" in
UUID=*)
dev=`blkid -U "${dev#UUID=}"`
;;
LABEL=*)
dev=`blkid -L "${dev#LABEL=}"`
;;
esac
echo $dev
}
get_block_dump_target()
{
local _target
_target=$(get_user_configured_dump_disk)
[ -n "$_target" ] && echo $(to_dev_name $_target) && return
#get rootfs device name
_target=$(get_root_fs_device)
[ -b "$_target" ] && echo $(to_dev_name $_target)
}
#handle the case user does not specify the dump target explicitly
handle_default_dump_target()
{
local _target
local _mntpoint
local _fstype
is_user_configured_dump_target && return
check_save_path_fs $SAVE_PATH
_mntpoint=$(get_mntpoint_from_path $SAVE_PATH)
_target=$(get_target_from_path $SAVE_PATH)
if [ "$_mntpoint" != "/" ]; then
SAVE_PATH=${SAVE_PATH##"$_mntpoint"}
_fstype=$(get_fs_type_from_target $_target)
if $(is_fs_type_nfs $_fstype); then
add_dracut_module "nfs"
fi
add_mount "$_target"
check_size fs $_target
fi
}
get_default_action_target()
{
local _target
local _action=$(grep "^default" /etc/kdump.conf 2>/dev/null | awk '{print $2}')
if [ -n "$_action" ] && [ "$_action" = "dump_to_rootfs" ]; then
#get rootfs device name
_target=$(findmnt -k -f -n -o SOURCE /)
[ -b "$_target" ] && echo $(to_dev_name $_target)
fi
return
}
get_override_resettable()
{
local override_resettable
override_resettable=$(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
}
# $1: function name
for_each_block_target()
{
local dev majmin
#check dump target
dev=$(get_block_dump_target)
if [ -n "$dev" ]; then
majmin=$(get_maj_min $dev)
check_block_and_slaves $1 $majmin && return 1
fi
#check rootfs when default action dump_to_rootfs is set
dev=$(get_default_action_target)
if [ -n "$dev" ]; then
majmin=$(get_maj_min $dev)
check_block_and_slaves $1 $majmin && return 2
fi
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 "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
if [ $_ret -eq 1 ]; then
_target=$(get_block_dump_target)
perror "Can not save vmcore to target device $_target . This device can not be initialized in kdump kernel as it is not resettable"
elif [ $_ret -eq 2 ]; then
_target=$(get_default_action_target)
perror "Rootfs device $_target is not resettable, can not be used as the default target, please specify a default action"
fi
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
while read config_opt config_val;
do
# remove inline comments after the end of a directive.
config_val=$(strip_comments $config_val)
case "$config_opt" in
extra_modules)
extra_modules="$extra_modules $config_val"
;;
ext[234]|xfs|btrfs|minix|nfs)
if ! findmnt $config_val >/dev/null; then
perror_exit "Dump target $config_val is probably not mounted."
fi
if [ "$config_opt" = "nfs" ]; then
add_dracut_module "nfs"
fi
add_mount "$config_val"
check_save_path_fs $(make_absolute_save_path $config_val)
check_size fs $config_val
;;
raw)
#checking raw disk writable
dd if=$config_val count=1 of=/dev/null > /dev/null 2>&1 || {
perror_exit "Bad raw disk $config_val"
}
_praw=$(get_persistent_dev $config_val)
if [ $? -ne 0 ]; then
exit 1
fi
add_dracut_arg "--device" "$_praw"
check_size raw $config_val
;;
ssh)
if strstr "$config_val" "@";
then
check_size ssh $config_val
mkdir_save_path_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"
;;
add dracut_args option to kdump.conf mkdumprd call dracut to rebuilding kdump initrd, sometimes passing extra dracut args is helpful. For example user can enable debug output with --debug, --printsize to print roughly increased initramfs size by each module, --omit-drivers to omit kernel modules, etc. This patch enables dracut_args option for passing extra args to dracut. Also it modifies add_dracut_arg() to treat a string with-in quote as single string because for dracut options which has its own args, the args need to be quoted and space seperated. If add_dracut_arg() gets an string read from kdump.conf and if that string contains double quotes, then while converting to positional parameters those double quotes are not interpreted. Hence if /etc/kdump.conf contains following. dracut_args --add-drivers "driver1 driver2" then add_dracut_args() sees following positional parameters $1= --add-drivers $2= "driver1 $3= driver2" Notice, double quotes have been ignored and parameters have been broken based on white space. Modify add_dracut_arg() to look for parameters starting with " and if one is found, it tries to merge all the next parameters till one is found with ending double quote. Hence effectively simulating following behavior. $1= --add-drivers $2= "driver1 driver2" [v1->v2]: address quoted substring in dracut_args, also handle the leading and ending spaces in substring. [v2->v3]: fix dracut arguments seperator in kdump.conf. [v3->v4]: improve changelog, thanks vivek. [v4->v5]: make the manpage more verbose [vivek]. Tested with below dracut_args test cases: 1. dracut_args --add-drivers "pcspkr virtio_net" --omit-drivers "sdhci-pci hid-logitech-dj e1000" 2. dracut_args --add-drivers " pcspkr virtio_net " --omit-drivers "sdhci-pci hid-logitech-dj e1000" Signed-off-by: Dave Young <dyoung@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
2013-04-15 02:12:05 +00:00
dracut_args)
add_dracut_arg $config_val
;;
*)
if [ -n $(echo $config_opt | grep "^#.*$") ]
then
continue
fi
;;
esac
done < $conf_file
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handle_default_dump_target
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if [ -n "$extra_modules" ]
then
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add_dracut_arg "--add-drivers" "$extra_modules"
fi
dracut "${dracut_args[@]}" "$@"
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_rc=$?
sync
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exit $_rc