[PATCH 00/10] All recent patches linearly

[PATCH 00/10] All recent patches linearly

[Michal Soltys]

As they kind of slowly started piling up and messing with each other.

Only new things are (last two patches):

- thorough checks for chosen/fallback terminal before calling shell
- emergency_shell moved into single place in dracut-lib, with two simple knobs
- added documentation for --ctty

Additionally,

The following changes since commit d239b550ce9e6a80342965974c4503cfde736fbe:

  explicitly verify bash version (2011-10-11 09:37:02 +0200)

  are available in the git repository at:
    git://git.hasevolq.net/dracut.git fixup


Michal Soltys (10):
  features: RUNDIR, imgdir, prefix, prefix_mnt and related changes
  features: RUNDIR, imgdir, ... [update 1]
  minor changes
  dracut: remove duplicate options
  dracut: detect lib paths more carefully
  check root candidates more carefully
  introduce optional job control
  job control fixup
  prepare common emergency_shell function (1), shell job control fixups (2)
  optional shell job control - add documentation

 dracut                           |  130 ++++++++++++++----------
 dracut-functions                 |   71 +++++++++-----
 dracut.8.xml                     |    9 ++
 dracut.kernel.7.xml              |   15 +++
 modules.d/10i18n/console_init    |    1 +
 modules.d/99base/dracut-lib.sh   |  109 ++++++++++++++++++++
 modules.d/99base/init            |  205 ++++++++++++++++++--------------------
 modules.d/99base/module-setup.sh |   14 ++-
 modules.d/99shutdown/shutdown    |   29 +-----
 9 files changed, 363 insertions(+), 220 deletions(-)

-- 
1.7.5.3

[PATCH 01/10] features: RUNDIR, imgdir, prefix, prefix_mnt and related changes

[Michal Soltys]

1) $prefix, $prefix_mnt

The prefix itself (and new prefix_mnt option) is used only during /run --move
(pre-pivot, preiously --bind), while internally - dracut files and /run are
kept _separately_ in $imgdir and $rundir.

$prefix is sanitized before use, and its final (adjusted) value is always
relative to /run (not being under /run has little point). If user provided
$prefix doesn't start with /run, or consists only of /run - it's assumed to be
/run relative. Otherwise (2 or more components and beginning with /run) it's
assumed to be absolute.

$prefix_mnt allows us to request tmpfs mount at $newrun/$prefix, before copying
dracut tree.

2) $RUNDIR (inside init only), $imgdir

The crux of changes are these two. Internal split, which previously was based
on $prefix is now based on $imgdir. All /run references from $imgdir point to
/run, which inside init is adjusted to /run -> $RUNDIR. All tmp references
point to just initramfs root's /tmp (as we don't care about the junk after
pivot).

This gives us decoupled runtime tree and dracut image tree. The latter can be
installed if $prefix is set or completely ignored. runtime is always --moved.
Furthermore, $RUNDIR is symlinked from run, so it can be easily kept fully
functional, with trivial symlink adjustment.

Everything in imgdir is symlinked from initramfs's root (similary as it's been
done until now).

All inst*() functions are aware of $imgdir; imgdir, prefix, prefix_mnt and
newroot are exported, and also available in init (after uppercasing, sourced
from simple config file).

Of course, /tmp and /run stuff has to be set differently during installation
phase (e.g. ..../var/run -> ${initdir}/run, etc.) and differenty during
initramfs execution (e.g. ..../var/run -> /run). In dracut script, it's
respectively "initial sewing pass" and "final sewing pass". The latter one also
verifies if all symlinks are valid.

This way of handling $prefix opens path to making it runtime argument (e.g.
rd.prefix).

3) /run ($RUNDIR) move

/run is moved to either $NEWROOT/run or if not possible - to /dev/.run (with
/dev/.initramfs -> .run/initramfs symlink). If $prefix is specified, contents
of $imgdir are copied to the $NEWRUN/$prefix or alternatively (if $prefix_mnt
is set), tmpfs is mounted at $NEWRUN/$prefix and then the $imgdir is copied;
init will refuse overmount, if the directory is already present.

4) udev and /dev/.udev vs /run/udev

There's possibility, that sufficiently new udev will prefer /run during
initramfs stage, while host may still be not run ready. This might lead to
losing certain db entries (e.g. lvm's). If we detect such situation, contents
of /run/udev are moved to /dev/.udev before pivoting.

5) enforcing options of premounted directories

For special directories - /proc, /sys, etc. - as we should assure that the
actual mount options are sane. Though the only realistically pre-mountable
thing is /dev (for now at least).

6) other smaller changes:

 - copying cp -a -t <dst> . after cd <src>, instead of <dst> <src>/* - as this
   also handles .* files (otherwise we would have to tinker with some crude
   globbing and/or dotglob)
 - We don't try to mimic host's directory layout anymore (if some directories
   are symlinked, which is rarely the case either way and serves little
   purpose)
 - removed certain mkdirs, that are guaranteed to be handled by dracut
---
 dracut                           |  115 +++++++++++++++++++------------
 dracut-functions                 |   50 +++++++-------
 modules.d/99base/init            |  137 ++++++++++++++++++++++++--------------
 modules.d/99base/module-setup.sh |   13 ++--
 4 files changed, 189 insertions(+), 126 deletions(-)

diff --git a/dracut b/dracut
index 205f5d1..1d5f2f4 100755
--- a/dracut
+++ b/dracut
@@ -53,7 +53,11 @@ Creates initial ramdisk images for preloading modules
   --no-kernel           Do not install kernel drivers and firmware files
   --strip               Strip binaries in the initramfs
   --nostrip             Do not strip binaries in the initramfs (default)
-  --prefix [DIR]        Prefix initramfs files with [DIR]
+  --prefix [DIR]        Prefix initramfs files with [DIR]. If DIR doesn't
+                        start with /run (or if it's the only component), it's
+                        assumed to be relative to /run.
+  --prefix_mnt          Copy initramfs into additional tmpfs mount, instead of
+                        directly into prefix subdirectory.
   --noprefix            Do not prefix initramfs files (default)
   --mdadmconf           Include local /etc/mdadm.conf
   --nomdadmconf         Do not include local /etc/mdadm.conf
@@ -222,6 +226,7 @@ while (($# > 0)); do
         --strip)       do_strip_l="yes";;
         --nostrip)     do_strip_l="no";;
         --noprefix)    prefix_l="/";;
+        --prefix_mnt)  prefix_mnt_l="yes";;
         --mdadmconf)   mdadmconf_l="yes";;
         --nomdadmconf) mdadmconf_l="no";;
         --lvmconf)     lvmconf_l="yes";;
@@ -378,8 +383,6 @@ stdloglvl=$((stdloglvl + verbosity_mod_l))
 
 [[ $drivers_dir_l ]] && drivers_dir=$drivers_dir_l
 [[ $do_strip_l ]] && do_strip=$do_strip_l
-[[ $prefix_l ]] && prefix=$prefix_l
-[[ $prefix = "/" ]] && unset prefix
 [[ $hostonly_l ]] && hostonly=$hostonly_l
 [[ $use_fstab_l ]] && use_fstab=$use_fstab_l
 [[ $mdadmconf_l ]] && mdadmconf=$mdadmconf_l
@@ -390,6 +393,7 @@ stdloglvl=$((stdloglvl + verbosity_mod_l))
 [[ $compress_l ]] && compress=$compress_l
 [[ $show_modules_l ]] && show_modules=$show_modules_l
 [[ $nofscks_l ]] && nofscks="yes"
+[[ $prefix_mnt_l ]] && prefix_mnt="yes"
 # eliminate IFS hackery when messing with fw_dir
 fw_dir=${fw_dir//:/ }
 
@@ -428,6 +432,19 @@ fi
 dracutfunctions=$dracutbasedir/dracut-functions
 export dracutfunctions
 
+# sanitize and handle prefix.
+# If /run is the only component, or if $prefix_l doesn't start with /run, then
+# the path is assumed to be relative to /run, otherwise it's absolute.
+# Final prefix is always set as relative to /run
+if [[ "$prefix_l" =~ [[:alnum:]] ]]; then
+    prefix=$(normalize_path "/$prefix_l")
+    prefix=${prefix#/}
+    prefix=${prefix#run/}
+else
+    unset prefix
+    unset prefix_mnt
+fi
+
 ddebug "Executing $0 $dracut_args"
 
 [[ $do_list = yes ]] && {
@@ -494,6 +511,7 @@ readonly initdir=$(mktemp --tmpdir=/var/tmp/ -d -t initramfs.XXXXXX)
     dfatal "mktemp failed."
     exit 1
 }
+readonly imgdir=/_img newroot=/sysroot
 
 # clean up after ourselves no matter how we die.
 trap 'ret=$?;[[ $keep ]] && echo "Not removing $initdir." >&2 || rm -rf "$initdir";exit $ret;' EXIT
@@ -508,48 +526,30 @@ export initdir dracutbasedir dracutmodules drivers \
     add_drivers mdadmconf lvmconf filesystems \
     use_fstab libdir usrlibdir fscks nofscks \
     stdloglvl sysloglvl fileloglvl kmsgloglvl logfile \
-    debug
-
-# Create some directory structure first
-[[ $prefix ]] && mkdir -m 0755 -p "${initdir}${prefix}"
-
-[[ -h /lib ]] || mkdir -m 0755 -p "${initdir}${prefix}/lib"
-[[ $prefix ]] && ln -sfn "${prefix#/}/lib" "$initdir/lib"
-
-if [[ $prefix ]]; then
-    for d in bin etc lib "$libdir" sbin tmp usr var; do
-        ln -sfn "${prefix#/}/${d#/}" "$initdir/$d"
-    done
-fi
+    debug imgdir prefix prefix_mnt newroot
 
+# initial directory layout + host safe symlinks
 if [[ $kernel_only != yes ]]; then
-    for d in bin etc lib "$libdir" sbin tmp usr var usr/bin usr/sbin; do
-        [[ -e "${initdir}${prefix}/$d" ]] && continue
-        if [ -h "/$d" ]; then
-            inst "/$d" "${prefix}/$d"
-        else
-            mkdir -m 0755 -p "${initdir}${prefix}/$d"
-        fi
-    done
-
-    for d in dev proc sys sysroot root run run/lock run/initramfs; do
-        if [ -h "/$d" ]; then
-            inst "/$d"
-        else
-            mkdir -m 0755 -p "$initdir/$d"
-        fi
+    mkdir -m 0755 -p \
+        "${initdir}${imgdir}"/{bin,etc,lib,${libdir#/},sbin,var,usr/{bin,sbin}} \
+        "${initdir}"/{dev,proc,sys,${newroot#/},root,run/{lock,initramfs},tmp}
+
+    # host safe symlinks (will be adjusted later), needed during inst*() calls
+    ln -sfn "${initdir}"/tmp      "${initdir}${imgdir}"/tmp
+    ln -sfn "${initdir}"/tmp      "${initdir}${imgdir}"/var/tmp
+    ln -sfn "${initdir}"/run      "${initdir}${imgdir}"/run
+    ln -sfn "${initdir}"/run      "${initdir}${imgdir}"/var/run
+    ln -sfn "${initdir}"/run/lock "${initdir}${imgdir}"/var/lock
+    # initial sewing pass
+    for d in bin etc lib "${libdir#/}" sbin var usr; do
+        ln -sfn "${imgdir#/}/$d" "${initdir}/$d"
     done
-
-    ln -sfn /run "$initdir/var/run"
-    ln -sfn /run/lock "$initdir/var/lock"
 else
-    for d in lib "$libdir"; do
-        [[ -e "${initdir}${prefix}/$d" ]] && continue
-        if [ -h "/$d" ]; then
-            inst "/$d" "${prefix}/$d"
-        else
-            mkdir -m 0755 -p "${initdir}${prefix}/$d"
-        fi
+    mkdir -m 0755 -p "${initdir}${imgdir}/"{lib,${libdir#/}}
+
+    # initial sewing pass
+    for d in lib "${libdir#/}"; do
+        ln -sfn "${imgdir#/}/$d" "${initdir}/$d"
     done
 fi
 
@@ -593,18 +593,20 @@ while pop include_src src && pop include_target tgt; do
             inst $src $tgt
         else
             ddebug "Including directory: $src"
-            mkdir -p "${initdir}/${tgt}"
+            mkdir -p "${initdir}${imgdir}/${tgt}"
             # check for preexisting symlinks, so we can cope with the
             # symlinks to $prefix
             for i in "$src"/*; do
                 [[ -e "$i" || -h "$i" ]] || continue
-                s=${initdir}/${tgt}/${i#$src/}
+                s=${initdir}${imgdir}/${tgt}/${i#$src/}
                 if [[ -d "$i" ]]; then
                     if ! [[ -e "$s" ]]; then
                         mkdir -m 0755 -p "$s"
                         chmod --reference="$i" "$s"
                     fi
-                    cp -a -t "$s" "$i"/*
+                    pushd "$i" &>/dev/null
+                    cp -a -t "$s" .
+                    popd &>/dev/null
                 else
                     cp -a -t "$s" "$i"
                 fi
@@ -620,7 +622,6 @@ while pop install_items items; do
 done
 unset item
 
-
 if [[ $kernel_only != yes ]]; then
     # make sure that library links are correct and up to date
     for f in /etc/ld.so.conf /etc/ld.so.conf.d/*; do
@@ -672,6 +673,30 @@ if strstr "$modules_loaded" " fips " && command -v prelink >/dev/null; then
     done
 fi
 
+# final sewing pass
+# remove helper /run & /tmp links, set symlinks to match initramfs's root, link
+# remaining directories (if any)
+if [[ $kernel_only != yes ]]; then
+    rm -f             "${initdir}${imgdir}"/{run,tmp}
+    ln -sfn /tmp      "${initdir}${imgdir}"/var/tmp
+    ln -sfn /run      "${initdir}${imgdir}"/var/run
+    ln -sfn /run/lock "${initdir}${imgdir}"/var/lock
+fi
+for d in "${initdir}${imgdir}"/*; do
+    s="${initdir}/${d##*/}"
+    if [[ -h ${s} ]]; then
+        # verify if everything is fine
+        t=$(readlink -e "${s}")
+        if [[ $t != $d ]]; then
+            dfatal "dracut: symlink mismatch ${d##*/} -/-> ${d#${initdir}/}"
+            exit 1
+        fi
+    else
+        ln -sfn "${imgdir#/}/${d##*/}" "${s}"
+    fi
+done
+
+# create the image
 if ! ( cd "$initdir"; find . |cpio -R 0:0 -H newc -o --quiet| \
     $compress > "$outfile"; ); then
     dfatal "dracut: creation of $outfile failed"
diff --git a/dracut-functions b/dracut-functions
index 1ef5269..3b971c7 100755
--- a/dracut-functions
+++ b/dracut-functions
@@ -269,13 +269,13 @@ check_vol_slaves() {
 
 # Install a directory, keeping symlinks as on the original system.
 # Example: if /lib points to /lib64 on the host, "inst_dir /lib/file"
-# will create ${initdir}/lib64, ${initdir}/lib64/file,
-# and a symlink ${initdir}/lib -> lib64.
+# will create ${initdir}${imgdir}/lib64, ${initdir}${imgdir}/lib64/file,
+# and a symlink ${initdir}${imgdir}/lib -> lib64.
 inst_dir() {
-    [[ -e ${initdir}"$1" ]] && return 0  # already there
+    [[ -e ${initdir}${imgdir}"$1" ]] && return 0  # already there
 
     local _dir="$1" _part="${1%/*}" _file
-    while [[ "$_part" != "${_part%/*}" ]] && ! [[ -e "${initdir}${_part}" ]]; do
+    while [[ "$_part" != "${_part%/*}" ]] && ! [[ -e "${initdir}${imgdir}${_part}" ]]; do
         _dir="$_part $_dir"
         _part=${_part%/*}
     done
@@ -290,12 +290,12 @@ inst_dir() {
             inst_dir "$target"
             inst_symlink "$_file"
         else
-            [[ -h ${initdir}$_file ]] && _file=$(readlink "${initdir}$_file")
+            [[ -h ${initdir}${imgdir}$_file ]] && _file=$(readlink "${initdir}${imgdir}$_file")
             # create directory
-            mkdir -m 0755 -p "${initdir}$_file" || return 1
+            mkdir -m 0755 -p "${initdir}${imgdir}$_file" || return 1
             if [[ -d "$_file" ]]; then
-                chmod --reference="$_file" "${initdir}$_file"
-                chmod u+w "${initdir}$_file"
+                chmod --reference="$_file" "${initdir}${imgdir}$_file"
+                chmod u+w "${initdir}${imgdir}$_file"
             fi
         fi
     done
@@ -303,15 +303,15 @@ inst_dir() {
 
 # $1 = file to copy to ramdisk
 # $2 (optional) Name for the file on the ramdisk
-# Location of the image dir is assumed to be $initdir
+# Location of the image dir is assumed to be ${initdir}${imgdir}
 # We never overwrite the target if it exists.
 inst_simple() {
     [[ -f $1 ]] || return 1
 
     local _src=$1 target="${2:-$1}"
-    if ! [[ -d ${initdir}$target ]]; then
-        [[ -e ${initdir}$target ]] && return 0
-        [[ -h ${initdir}$target ]] && return 0
+    if ! [[ -d ${initdir}${imgdir}$target ]]; then
+        [[ -e ${initdir}${imgdir}$target ]] && return 0
+        [[ -h ${initdir}${imgdir}$target ]] && return 0
         inst_dir "${target%/*}"
     fi
     # install checksum files also
@@ -319,7 +319,7 @@ inst_simple() {
         inst "${_src%/*}/.${_src##*/}.hmac" "${target%/*}/.${target##*/}.hmac"
     fi
     ddebug "Installing $_src"
-    cp --sparse=always -pfL "$_src" "${initdir}$target" 
+    cp --sparse=always -pfL "$_src" "${initdir}${imgdir}$target"
 }
 
 # find symlinks linked to given library file
@@ -352,7 +352,7 @@ rev_lib_symlinks() {
 # is referenced.
 inst_library() {
     local _src=$1 _dest=${2:-$1} _lib _reallib _symlink
-    [[ -e $initdir$_dest ]] && return 0
+    [[ -e ${initdir}${imgdir}$_dest ]] && return 0
     if [[ -L $_src ]]; then
         # install checksum files also
         if [[ -e "${_src%/*}/.${_src##*/}.hmac" ]]; then
@@ -361,14 +361,14 @@ inst_library() {
         _reallib=$(readlink -f "$_src")
         inst_simple "$_reallib" "$_reallib"
         inst_dir "${_dest%/*}"
-        ln -sfn $(convert_abs_rel "${_dest}" "${_reallib}") "${initdir}${_dest}"
+        ln -sfn $(convert_abs_rel "${_dest}" "${_reallib}") "${initdir}${imgdir}${_dest}"
     else
         inst_simple "$_src" "$_dest"
     fi
 
     # Create additional symlinks.  See rev_symlinks description.
     for _symlink in $(rev_lib_symlinks $_src) $(rev_lib_symlinks $_reallib); do
-        [[ ! -e $initdir$_symlink ]] && {
+        [[ ! -e ${initdir}${imgdir}$_symlink ]] && {
             ddebug "Creating extra symlink: $_symlink"
             inst_symlink $_symlink
         }
@@ -396,7 +396,7 @@ inst_binary() {
     _bin=$(find_binary "$1") || return 1
     _target=${2:-$_bin}
     inst_symlink $_bin $_target && return 0
-    [[ -e $initdir$_target ]] && return 0
+    [[ -e ${initdir}${imgdir}$_target ]] && return 0
 
     # If the binary being installed is also a library, add it to the loop.
     _so_regex='([^ ]*/lib[^/]*/[^ ]*\.so[^ ]*)'
@@ -414,7 +414,7 @@ inst_binary() {
         fi
         [[ $_line =~ $_so_regex ]] || continue
         _file=${BASH_REMATCH[1]}
-        [[ -e ${initdir}$_file ]] && continue
+        [[ -e ${initdir}${imgdir}$_file ]] && continue
 
         # See if we are loading an optimized version of a shared lib.
         if [[ $_file =~ $_lib_regex ]]; then
@@ -451,7 +451,7 @@ inst_script() {
 
 # same as above, but specialized for symlinks
 inst_symlink() {
-    local _src=$1 _target=$initdir${2:-$1} _realsrc
+    local _src=$1 _target=${initdir}${imgdir}${2:-$1} _realsrc
     [[ -L $1 ]] || return 1
     [[ -L $_target ]] && return 0
     _realsrc=$(readlink -f "$_src")
@@ -459,7 +459,7 @@ inst_symlink() {
     if [[ -d $_realsrc ]]; then
         inst_dir "$_realsrc"
     else
-        inst "$_realsrc" && mkdir -m 0755 -p "${_target%/*}" 
+        inst "$_realsrc" && mkdir -m 0755 -p "${_target%/*}"
     fi
     if [[ -e "${_src}" ]]; then
         ln -sfn $(convert_abs_rel "${_src}" "${_realsrc}") "$_target"
@@ -604,9 +604,9 @@ inst_decompress() {
             _realsrc="$(readlink -f ${_src})" # symlink target with extension
             _dst="${_src%.*}" # symlink without extension
             _realdst="${_realsrc%.*}" # symlink target without extension
-            mksubdirs "${initdir}/${_src}"
+            mksubdirs "${initdir}${imgdir}/${_src}"
             # Create symlink without extension to target without extension.
-            ln -sfn "${_realdst}" "${initdir}/${_dst}"
+            ln -sfn "${_realdst}" "${initdir}${imgdir}/${_dst}"
         fi
 
         # If the source is symlink we operate on its target.
@@ -614,7 +614,7 @@ inst_decompress() {
         inst ${_src}
         # Decompress with chosen tool.  We assume that tool changes name e.g.
         # from 'name.gz' to 'name'.
-        ${_cmd} "${initdir}${_src}"
+        ${_cmd} "${initdir}${imgdir}${_src}"
     done
 }
 
@@ -787,7 +787,7 @@ check_module_dir() {
 # $1 = full path to kernel module to install
 install_kmod_with_fw() {
     # no need to go further if the module is already installed
-    [[ -e "${initdir}/lib/modules/$kernel/${1##*/lib/modules/$kernel/}" ]] \
+    [[ -e "${initdir}${imgdir}/lib/modules/$kernel/${1##*/lib/modules/$kernel/}" ]] \
         && return 0
     inst_simple "$1" "/lib/modules/$kernel/${1##*/lib/modules/$kernel/}" \
         || return $?
@@ -915,7 +915,7 @@ instmods() {
 
                 # if we are already installed, skip this module and go on
                 # to the next one.
-                [[ -f $initdir/$1 ]] && return
+                [[ -f ${initdir}${imgdir}/$1 ]] && return
 
                 # If we are building a host-specific initramfs and this
                 # module is not already loaded, move on to the next one.
diff --git a/modules.d/99base/init b/modules.d/99base/init
index 06d61a8..0970a48 100755
--- a/modules.d/99base/init
+++ b/modules.d/99base/init
@@ -66,25 +66,31 @@ emergency_shell()
     fi
 }
 
-NEWROOT="/sysroot"
-[ -d $NEWROOT ] || mkdir -p -m 0755 $NEWROOT
-
 trap "emergency_shell Signal caught!" 0
 OLDPATH=$PATH
 PATH=/usr/sbin:/usr/bin:/sbin:/bin
 export PATH
 
 RD_DEBUG=""
+. /etc/dracut-init.conf
 . /lib/dracut-lib.sh
 
 [ -c /dev/null ] || mknod -m 0666 /dev/null c 1 3
 
-# mount some important things
-[ ! -d /proc/self ] && \
-    mount -t proc -o nosuid,noexec,nodev proc /proc >/dev/null 2>&1
+# mount some important things; if something is already mounted,
+# we sanitize mount options by remounting
+# note: although -t would be ignored during remount, we play
+# it safe and make sure -t is not specified in such case
+# note: at this point, only /dev can be premounted by kernel, so
+# maybe just skip those checks altogether ?
+
+_opt="-o nosuid,noexec,nodev"; _fs="-t proc"
+[ -d /proc/self ] && { _opt="$_opt,remount"; unset _fs; }
+mount $_fs $_opt proc /proc >/dev/null 2>&1
 
-[ ! -d /sys/kernel ] && \
-    mount -t sysfs -o nosuid,noexec,nodev sysfs /sys >/dev/null 2>&1
+_opt="-o nosuid,noexec,nodev"; _fs="-t sysfs"
+[ -d /sys/kernel ] && { _opt="$_opt,remount"; unset _fs; }
+mount $_fs $_opt sysfs /sys >/dev/null 2>&1
 
 if [ -x /lib/systemd/systemd-timestamp ]; then
     RD_TIMESTAMP=$(/lib/systemd/systemd-timestamp)
@@ -101,44 +107,50 @@ if [ "$RD_DEBUG" = "yes" ]; then
     [ -n "$a" ] && [ $a -ge 8 ] && unset DRACUT_QUIET
 fi
 
-if ! ismounted /dev; then
-    # try to mount devtmpfs
-    if ! mount -t devtmpfs -o mode=0755,nosuid devtmpfs /dev >/dev/null 2>&1; then
-        # if it failed fall back to normal tmpfs
-        mount -t tmpfs -o mode=0755,nosuid tmpfs /dev >/dev/null 2>&1
-        # Make some basic devices first, let udev handle the rest
-        mknod -m 0666 /dev/null c 1 3
-        mknod -m 0666 /dev/ptmx c 5 2
-        mknod -m 0600 /dev/console c 5 1
-        mknod -m 0660 /dev/kmsg c 1 11
-    fi
+_opt="-o mode=0755,nosuid,exec"; _fs="-t devtmpfs"
+ismounted /dev && { _opt="$_opt,remount"; unset _fs; }
+if ! mount $_fs $_opt devtmpfs /dev >/dev/null 2>&1; then
+    # if it failed (remount can't fail - no need to redo $_opt), fall back to
+    # normal tmpfs
+    mount -t tmpfs $_opt tmpfs /dev >/dev/null 2>&1
+    # Make some basic devices first, let udev handle the rest
+    mknod -m 0666 /dev/null c 1 3
+    mknod -m 0666 /dev/ptmx c 5 2
+    mknod -m 0600 /dev/console c 5 1
+    mknod -m 0660 /dev/kmsg c 1 11
 fi
 
-# prepare the /dev directory
+# prepare the /dev directory (note: newer udevd takes care of it automatically)
 [ ! -h /dev/fd ] && ln -s /proc/self/fd /dev/fd >/dev/null 2>&1
 [ ! -h /dev/stdin ] && ln -s /proc/self/fd/0 /dev/stdin >/dev/null 2>&1
 [ ! -h /dev/stdout ] && ln -s /proc/self/fd/1 /dev/stdout >/dev/null 2>&1
 [ ! -h /dev/stderr ] && ln -s /proc/self/fd/2 /dev/stderr >/dev/null 2>&1
 
-if ! ismounted /dev/pts; then
-    mkdir -m 0755 /dev/pts
-    mount -t devpts -o gid=5,mode=620,noexec,nosuid devpts /dev/pts >/dev/null 2>&1
-fi
-
-if ! ismounted /dev/shm; then
-    mkdir -m 0755 /dev/shm
-    mount -t tmpfs -o mode=1777,nosuid,nodev tmpfs /dev/shm >/dev/null 2>&1
-fi
-
-if ! ismounted /run; then
-    mkdir -m 0755 /newrun
-    mount -t tmpfs -o mode=0755,nosuid,nodev tmpfs /newrun >/dev/null 2>&1
-    cp -a -t /newrun /run/*
-    mount --move /newrun /run
-    rm -fr /newrun
-fi
-
-[ -d /run/initramfs ] || mkdir -p -m 0755 /run/initramfs
+_opt="-o gid=5,mode=620,noexec,nosuid"; _fs="-t devpts"
+ismounted /dev/pts && { _opt="$_opt,remount"; unset _fs; } || mkdir -m 0755 /dev/pts
+mount $_fs $_opt devpts /dev/pts >/dev/null 2>&1
+
+_opt="-o mode=1777,nosuid,nodev"; _fs="-t tmpfs"
+ismounted /dev/shm && { _opt="$_opt,remount"; unset _fs; } || mkdir -m 0755 /dev/shm
+mount $_fs $_opt tmpfs /dev/shm >/dev/null 2>&1
+
+# Prepare proper tmpfs mount for /run:
+# - /run is just a symlink to real staging area. This allows us to be
+#   independent from any mount place, with trivial symlink manipulation
+# - checking if /run is premounted, is pretty crazy in initramfs ...
+
+_opt="-o mode=0755,nosuid,nodev,exec"; _fs="-t tmpfs"
+RUNDIR=/_run
+ismounted /run && { _opt="$_opt,remount"; unset _fs; }
+mkdir -m 0755 -p $RUNDIR
+# move + remount or mount
+[ -z "$_fs" ] && mount --move /run $RUNDIR
+mount $_fs $_opt tmpfs $RUNDIR >/dev/null 2>&1
+# copy if mount
+[ -z "$_fs" ] || { cd /run; cp -a -t $RUNDIR .; cd /; }
+# set symlink
+rm -rf /run
+ln -sfn ${RUNDIR#/} /run
 
 UDEVVERSION=$(udevadm --version)
 if [ $UDEVVERSION -gt 166 ]; then
@@ -410,20 +422,43 @@ else
 fi
 [ "$RD_DEBUG" = "yes" ] && set -x
 
-if [ -d "$NEWROOT"/run ]; then
-    NEWRUN="${NEWROOT}/run"
-    mount --bind /run "$NEWRUN"
-    NEWINITRAMFSROOT="$NEWRUN/initramfs"
+# /run move, udev adjustment (if applicable), prefix handling
+if [ -d "$NEWROOT/run" ]; then
+    NEWRUN="$NEWROOT/run"
+else
+    NEWRUN=/dev/.run
+    mkdir -p -m 0755 "$NEWRUN"
+    [ -n "$PREFIX" ] && ln -sfn .run/initramfs /dev/.initramfs
+    # if initramfs's udev uses /run by default, but the host is
+    # still /run-less, we should copy udev's data to legacy
+    # /dev/.udev, so the necessary info is available for the host
+    # (e.g. lvm db entries)
+    if [ -d /run/udev/data -o -d /run/udev/db ]; then
+        mkdir -p -m 0755 /dev/.udev
+        cd /run/udev
+        cp -a -t /dev/.udev .
+        cd /
+        rm -rf /run/udev
+    fi
+fi
 
-    if [ "$NEWINITRAMFSROOT/lib" -ef "/lib" ]; then
-        for d in bin etc lib lib64 sbin tmp usr var; do
-            [ -h /$d ] && ln -fsn $NEWINITRAMFSROOT/$d /$d
-        done
+mount --move "$RUNDIR" "$NEWRUN"
+ln -sfn "${NEWRUN#/}" /run
+
+if [ -n "$PREFIX" ]; then
+    if [ -d "$NEWRUN/$PREFIX" ]; then
+        [ -n "$PREFIX_MNT" ] &&
+            warn "'$NEWRUN/$PREFIX' already exists, dracut files will be copied directly to this directory"
+        unset PREFIX_MNT
+    else
+        mkdir -p -m 0755 "$NEWRUN/$PREFIX"
     fi
-else
-    NEWRUN=/dev/.initramfs
-    mkdir -m 0755 "$NEWRUN"
-    mount --bind /run/initramfs "$NEWRUN"
+    if [ -n "$PREFIX_MNT" ]; then
+        mount -t tmpfs -o mode=0755,nosuid,nodev,exec tmpfs "$NEWRUN/$PREFIX"
+    fi
+    cd "$IMGDIR"
+    cp -a -t "$NEWRUN/$PREFIX" .
+    cd /
 fi
 
 wait_for_loginit
diff --git a/modules.d/99base/module-setup.sh b/modules.d/99base/module-setup.sh
index f6dc920..2a9b643 100755
--- a/modules.d/99base/module-setup.sh
+++ b/modules.d/99base/module-setup.sh
@@ -12,7 +12,7 @@ depends() {
 }
 
 install() {
-    local _d
+    local _d _x
     dracut_install mount mknod mkdir modprobe pidof sleep chroot \
         sed ls flock cp mv dmesg rm ln rmmod mkfifo umount readlink
     dracut_install -o less
@@ -25,7 +25,6 @@ install() {
     inst "$moddir/initqueue" "/sbin/initqueue"
     inst "$moddir/loginit" "/sbin/loginit"
 
-    [ -e "${initdir}/lib" ] || mkdir -m 0755 -p ${initdir}/lib
     mkdir -m 0755 -p ${initdir}/lib/dracut
     mkdir -m 0755 -p ${initdir}/lib/dracut/hooks
     for _d in $hookdirs emergency \
@@ -33,13 +32,17 @@ install() {
         mkdir -m 0755 -p ${initdir}/lib/dracut/hooks/$_d
     done
 
-    mkdir -p ${initdir}/tmp
-
     dracut_install switch_root || dfatal "Failed to install switch_root"
 
     inst "$moddir/dracut-lib.sh" "/lib/dracut-lib.sh"
     inst_hook cmdline 10 "$moddir/parse-root-opts.sh"
-    mkdir -p "${initdir}/var"
+
     [ -x /lib/systemd/systemd-timestamp ] && inst /lib/systemd/systemd-timestamp
+
+    # export certain settings to init
+    for _d in newroot imgdir prefix prefix_mnt; do
+        _x=$(echo $_d | tr "a-z" "A-Z")
+        [ -n "$_d" ] && echo "${_x}=${!_d}" >>${initdir}/etc/dracut-init.conf
+    done
 }
 
-- 
1.7.5.3

[PATCH 02/10] features: RUNDIR, imgdir, ... [update 1]

[Michal Soltys]

Make sure we actually mimic host's structure to not end with duplicate
files (harmless but wasteful) on hosts, where lib and lib64 point to the
same place.

We detect symlink/dir presence in the creation loop, so we don't have to
worry about $[usr]libdir.

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 dracut |   30 ++++++++++++++++--------------
 1 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/dracut b/dracut
index 1d5f2f4..191998a 100755
--- a/dracut
+++ b/dracut
@@ -530,9 +530,13 @@ export initdir dracutbasedir dracutmodules drivers \
 
 # initial directory layout + host safe symlinks
 if [[ $kernel_only != yes ]]; then
+    for d in /{bin,sbin,etc,lib{,64},var,usr{,/{bin,sbin,lib{,64}}}}; do
+        if [[ -h $d ]]; then inst_symlink $d
+        elif [[ -d $d ]]; then inst_dir $d; fi
+    done
+
     mkdir -m 0755 -p \
-        "${initdir}${imgdir}"/{bin,etc,lib,${libdir#/},sbin,var,usr/{bin,sbin}} \
-        "${initdir}"/{dev,proc,sys,${newroot#/},root,run/{lock,initramfs},tmp}
+        "${initdir}"/{dev,proc,sys,${newroot#/},root,run{,/{lock,initramfs}},tmp}
 
     # host safe symlinks (will be adjusted later), needed during inst*() calls
     ln -sfn "${initdir}"/tmp      "${initdir}${imgdir}"/tmp
@@ -540,18 +544,16 @@ if [[ $kernel_only != yes ]]; then
     ln -sfn "${initdir}"/run      "${initdir}${imgdir}"/run
     ln -sfn "${initdir}"/run      "${initdir}${imgdir}"/var/run
     ln -sfn "${initdir}"/run/lock "${initdir}${imgdir}"/var/lock
-    # initial sewing pass
-    for d in bin etc lib "${libdir#/}" sbin var usr; do
-        ln -sfn "${imgdir#/}/$d" "${initdir}/$d"
-    done
 else
-    mkdir -m 0755 -p "${initdir}${imgdir}/"{lib,${libdir#/}}
-
-    # initial sewing pass
-    for d in lib "${libdir#/}"; do
-        ln -sfn "${imgdir#/}/$d" "${initdir}/$d"
+    for d in /lib{,64}; do
+        if [[ -h $d ]]; then inst_symlink $d
+        elif [[ -d $d ]]; then inst_dir $d; fi
     done
 fi
+# initial sewing pass
+for d in "${initdir}${imgdir}"/*; do
+    ln -sfn "${imgdir#/}/${d##*/}" "${initdir}/${d##*/}"
+done
 
 # check all our modules to see if they should be sourced.
 # This builds a list of modules that we will install next.
@@ -686,13 +688,13 @@ for d in "${initdir}${imgdir}"/*; do
     s="${initdir}/${d##*/}"
     if [[ -h ${s} ]]; then
         # verify if everything is fine
-        t=$(readlink -e "${s}")
-        if [[ $t != $d ]]; then
+        t=$(readlink "${s}")
+        if [[ $t != ${d#${initdir}/} ]]; then
             dfatal "dracut: symlink mismatch ${d##*/} -/-> ${d#${initdir}/}"
             exit 1
         fi
     else
-        ln -sfn "${imgdir#/}/${d##*/}" "${s}"
+        ln -sfn "${d#${initdir}/}" "${s}"
     fi
 done
 
-- 
1.7.5.3

[PATCH 03/10] minor changes

[Michal Soltys]

- in 10i18n - do stty -iutf8 on non-utf8 consoles, for consistency with
  iutf8 on utf8 ones
- vim modeline in xml file

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 dracut.kernel.7.xml           |    1 +
 modules.d/10i18n/console_init |    1 +
 2 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/dracut.kernel.7.xml b/dracut.kernel.7.xml
index 8d50d94..0571031 100644
--- a/dracut.kernel.7.xml
+++ b/dracut.kernel.7.xml
@@ -1,5 +1,6 @@
 <?xml version='1.0' encoding='UTF-8'?>
 <!-- This document was created with Syntext Serna Free. --><!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd" []>
+<!-- vim: set ts=8 sts=2 sw=2 et: -->
 <refentry id="dracutkernel7">
   <refentryinfo>
     <title>dracut.kernel</title>
diff --git a/modules.d/10i18n/console_init b/modules.d/10i18n/console_init
index 110cb0a..b46046b 100755
--- a/modules.d/10i18n/console_init
+++ b/modules.d/10i18n/console_init
@@ -22,6 +22,7 @@ set_terminal() {
         stty -F ${dev} iutf8
     else
         printf '\033%%@' >&7
+        stty -F ${dev} -iutf8
     fi
 }
 
-- 
1.7.5.3

[PATCH 04/10] dracut: remove duplicate options

[Michal Soltys]

'-I' and '--fwdir' were both read_arg and push_arg, and the latter has
priority.

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 dracut |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/dracut b/dracut
index 191998a..a93dade 100755
--- a/dracut
+++ b/dracut
@@ -216,8 +216,6 @@ while (($# > 0)); do
         -c|--conf)     read_arg conffile             "$@" || shift;;
         --confdir)     read_arg confdir              "$@" || shift;;
         -L|--stdlog)   read_arg stdloglvl_l          "$@" || shift;;
-        -I|--install)  read_arg install_items        "$@" || shift;;
-        --fwdir)       read_arg fw_dir_l             "$@" || shift;;
         --compress)    read_arg compress_l           "$@" || shift;;
         --prefix)      read_arg prefix_l             "$@" || shift;;
         -f|--force)    force=yes;;
-- 
1.7.5.3

[PATCH 05/10] dracut: detect lib paths more carefully

[Michal Soltys]

- consider that they can point to the same directory - in such case
  ignore the one that is a symlink
- move the detection function to dracut-functions

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 dracut           |   12 ++----------
 dracut-functions |   21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/dracut b/dracut
index a93dade..115f1c4 100755
--- a/dracut
+++ b/dracut
@@ -456,16 +456,8 @@ ddebug "Executing $0 $dracut_args"
 }
 
 # Detect lib paths
-[[ $libdir ]] || for libdir in /lib64 /lib; do
-    [[ -d $libdir ]] && break
-done || {
-    dfatal 'No lib directory?!!!'
-    exit 1
-}
-
-[[ $usrlibdir ]] || for usrlibdir in /usr/lib64 /usr/lib; do
-    [[ -d $usrlibdir ]] && break
-done || dwarn 'No usr/lib directory!'
+libdir="$(det_lib_paths)" || { dfatal 'No lib directory?!!!'; exit 1; }
+usrlibdir="$(det_lib_paths /usr)" || dwarn 'No usr/lib directory!'
 
 # This is kinda legacy -- eventually it should go away.
 case $dracutmodules in
diff --git a/dracut-functions b/dracut-functions
index 3b971c7..7b6aa5a 100755
--- a/dracut-functions
+++ b/dracut-functions
@@ -958,3 +958,24 @@ instmods() {
     | egrep -v 'FATAL: Module .* not found.' | derror
     return $?
 }
+
+# determine lib paths in specified prefix
+# if they point to the same, ignore the one that is a symlink
+# prefer lib64 over lib
+function det_lib_paths() {
+    local _lib _d _d64
+    _d=$(readlink -e "$1/lib")
+    _d64=$(readlink -e "$1/lib64")
+    if [[ $_d = $_d64 ]]; then
+        [[ -h $1/lib ]] && unset _d
+        [[ -h $1/lib64 ]] && unset _d64
+    fi
+    if [[ -n $_d64 ]]; then
+        _lib=$1/lib64
+    elif [[ -n $_d ]]; then
+        _lib=$1/lib
+    else
+        return 1
+    fi
+    echo "$_lib"
+}
-- 
1.7.5.3

[PATCH 06/10] check root candidates more carefully

[Michal Soltys]

This is from the following thread:

http://thread.gmane.org/gmane.linux.raid/35753/focus=35795

Additional tests + more specific info.

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 modules.d/99base/dracut-lib.sh |   11 +++++++++++
 modules.d/99base/init          |   12 ++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/modules.d/99base/dracut-lib.sh b/modules.d/99base/dracut-lib.sh
index 62c3bf5..cf5aae6 100755
--- a/modules.d/99base/dracut-lib.sh
+++ b/modules.d/99base/dracut-lib.sh
@@ -544,3 +544,14 @@ foreach_uuid_until() (
 
     return 1
 )
+
+usable_root() {
+    local _d
+    [ -d $1 ] || return 1
+    for _d in "$1"/{etc,proc,sys,dev,tmp,usr,var}; do
+        [ -e $_d ] || return 1
+    done
+    [ -e "$1/bin" -o -e "$1/sbin" ] || return 1
+    [ -e "$1/lib" -o -e "$1/lib64" ] || return 1
+    return 0
+}
diff --git a/modules.d/99base/init b/modules.d/99base/init
index 0970a48..bc5d2ba 100755
--- a/modules.d/99base/init
+++ b/modules.d/99base/init
@@ -298,10 +298,18 @@ getarg 'rd.break=mount' 'rdbreak=mount' && emergency_shell -n mount "Break mount
 # be sourced any number of times. As soon as one suceeds, no more are sourced.
 i=0
 while :; do
-    [ -d "$NEWROOT/proc" ] && break;
+    if ismounted "$NEWROOT"; then
+        usable_root "$NEWROOT" && break;
+        umount "$NEWROOT"
+    fi
     for f in $hookdir/mount/*.sh; do
         [ -f "$f" ] && . "$f"
-        [ -d "$NEWROOT/proc" ] && break;
+        if ismounted "$NEWROOT"; then
+            usable_root "$NEWROOT" && break;
+            warn "$NEWROOT has no proper rootfs layout, ignoring and removing offending mount hook"
+            umount "$NEWROOT"
+            rm -f "$f"
+        fi
     done
 
     i=$(($i+1))
-- 
1.7.5.3

[PATCH 07/10] introduce optional job control

[Michal Soltys]

Option --ctty will optionally add setsid binary to dracut's image.

During runtime, if rd.ctty is set and is a character device,
emergency shells will be spawned with job control.

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 dracut                           |    3 ++-
 modules.d/99base/init            |   10 ++++++++--
 modules.d/99base/module-setup.sh |    1 +
 modules.d/99shutdown/shutdown    |   11 +++++++++--
 4 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/dracut b/dracut
index 115f1c4..4cfcab8 100755
--- a/dracut
+++ b/dracut
@@ -231,6 +231,7 @@ while (($# > 0)); do
         --nolvmconf)   lvmconf_l="no";;
         --debug)       debug="yes";;
         --profile)     profile="yes";;
+        --ctty)        cttyhack="yes";;
         -v|--verbose)  ((verbosity_mod_l++));;
         -q|--quiet)    ((verbosity_mod_l--));;
         -l|--local)    allowlocal="yes" ;;
@@ -514,7 +515,7 @@ chmod 755 "$initdir"
 export initdir dracutbasedir dracutmodules drivers \
     fw_dir drivers_dir debug no_kernel kernel_only \
     add_drivers mdadmconf lvmconf filesystems \
-    use_fstab libdir usrlibdir fscks nofscks \
+    use_fstab libdir usrlibdir fscks nofscks cttyhack \
     stdloglvl sysloglvl fileloglvl kmsgloglvl logfile \
     debug imgdir prefix prefix_mnt newroot
 
diff --git a/modules.d/99base/init b/modules.d/99base/init
index bc5d2ba..e532bfe 100755
--- a/modules.d/99base/init
+++ b/modules.d/99base/init
@@ -40,6 +40,7 @@ wait_for_loginit()
 
 emergency_shell()
 {
+    local _ctty
     set +e
     if [ "$1" = "-n" ]; then
         _rdshell_name=$2
@@ -57,8 +58,13 @@ emergency_shell()
         echo "Dropping to debug shell."
         echo
         export PS1="$_rdshell_name:\${PWD}# "
-        [ -e /.profile ] || echo "exec 0<>/dev/console 1<>/dev/console 2<>/dev/console" > /.profile
-        sh -i -l
+        [ -e /.profile ] || >/.profile
+        _ctty="$(getarg rd.ctty=)" && _ctty="/dev/${_ctty##*/}"
+        if type setsid >/dev/null 2>&1 && [ -c "$_ctty" ] ; then
+            setsid sh -i -l 0<$_ctty 1>$_ctty 2>&1
+        else
+            sh -i -l
+        fi
     else
         warn "Boot has failed. To debug this issue add \"rdshell\" to the kernel command line."
         # cause a kernel panic
diff --git a/modules.d/99base/module-setup.sh b/modules.d/99base/module-setup.sh
index 2a9b643..4c64bca 100755
--- a/modules.d/99base/module-setup.sh
+++ b/modules.d/99base/module-setup.sh
@@ -16,6 +16,7 @@ install() {
     dracut_install mount mknod mkdir modprobe pidof sleep chroot \
         sed ls flock cp mv dmesg rm ln rmmod mkfifo umount readlink
     dracut_install -o less
+    [[ $cttyhack = yes ]] && dracut_install -o setsid
     if [ ! -e "${initdir}/bin/sh" ]; then
         dracut_install bash
         (ln -s bash "${initdir}/bin/sh" || :)
diff --git a/modules.d/99shutdown/shutdown b/modules.d/99shutdown/shutdown
index a31a95d..9473b5b 100755
--- a/modules.d/99shutdown/shutdown
+++ b/modules.d/99shutdown/shutdown
@@ -13,6 +13,7 @@ export TERM=linux
 
 emergency_shell()
 {
+    local _ctty
     set +e
     if [ "$1" = "-n" ]; then
         _rdshell_name=$2
@@ -29,8 +30,14 @@ emergency_shell()
         echo "Dropping to debug shell."
         echo
         export PS1="$_rdshell_name:\${PWD}# "
-        [ -e /.profile ] || echo "exec 0<>/dev/console 1<>/dev/console 2<>/dev/console" > /.profile
-        sh -i -l
+        [ -e /.profile ] || >/.profile
+        _ctty="$(getarg rd.ctty=)" && _ctty="/dev/${_ctty##*/}"
+        if type setsid >/dev/null 2>&1 && [ -c "$_ctty" ] ; then
+            _ctty=/dev/${_ctty##*/}
+            setsid sh -i -l 0<$_ctty 1>$_ctty 2>&1
+        else
+            sh -i -l
+        fi
     else
         exec /lib/systemd/systemd-shutdown "$@"
         warn "Shutdown has failed. To debug this issue add \"rdshell\" to the kernel command line."
-- 
1.7.5.3

[PATCH 08/10] job control fixup

[Michal Soltys]

- in case no ctty was provided, shell was spawned without caring about
  /dev/console

Also, the ctty is more opportunistic. If the image was generated with
--ctty, we will fallback to /dev/tty1 if rc.ctty is invalid or missing.
Otherwise we spawn standard shell on /dev/console

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 modules.d/99base/init         |    8 +++++---
 modules.d/99shutdown/shutdown |    9 +++++----
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/modules.d/99base/init b/modules.d/99base/init
index e532bfe..3da6abd 100755
--- a/modules.d/99base/init
+++ b/modules.d/99base/init
@@ -59,11 +59,13 @@ emergency_shell()
         echo
         export PS1="$_rdshell_name:\${PWD}# "
         [ -e /.profile ] || >/.profile
-        _ctty="$(getarg rd.ctty=)" && _ctty="/dev/${_ctty##*/}"
-        if type setsid >/dev/null 2>&1 && [ -c "$_ctty" ] ; then
+        _ctty=/dev/console
+        if type setsid >/dev/null 2>&1; then
+            _ctty="$(getarg rd.ctty=)" && _ctty="/dev/${_ctty##*/}"
+            [ -c "$_ctty" ] || _ctty=/dev/tty1
             setsid sh -i -l 0<$_ctty 1>$_ctty 2>&1
         else
-            sh -i -l
+            sh -i -l 0<$_ctty 1>$_ctty 2>&1
         fi
     else
         warn "Boot has failed. To debug this issue add \"rdshell\" to the kernel command line."
diff --git a/modules.d/99shutdown/shutdown b/modules.d/99shutdown/shutdown
index 9473b5b..21bb37f 100755
--- a/modules.d/99shutdown/shutdown
+++ b/modules.d/99shutdown/shutdown
@@ -31,12 +31,13 @@ emergency_shell()
         echo
         export PS1="$_rdshell_name:\${PWD}# "
         [ -e /.profile ] || >/.profile
-        _ctty="$(getarg rd.ctty=)" && _ctty="/dev/${_ctty##*/}"
-        if type setsid >/dev/null 2>&1 && [ -c "$_ctty" ] ; then
-            _ctty=/dev/${_ctty##*/}
+        _ctty=/dev/console
+        if type setsid >/dev/null 2>&1; then
+            _ctty="$(getarg rd.ctty=)" && _ctty="/dev/${_ctty##*/}"
+            [ -c "$_ctty" ] || _ctty=/dev/tty1
             setsid sh -i -l 0<$_ctty 1>$_ctty 2>&1
         else
-            sh -i -l
+            sh -i -l 0<$_ctty 1>$_ctty 2>&1
         fi
     else
         exec /lib/systemd/systemd-shutdown "$@"
-- 
1.7.5.3

[PATCH 09/10] prepare common emergency_shell function (1), shell job control fixups (2)

[Michal Soltys]

1) prepare common emergency_shell

emergency_shell functions from 99base/init and 99shutdown/shutdown were
very similar, which forced to do similar changes in both places

The core functionality was moved to 99base/dracut-lib.sh as
emergency_shell_core(), which is now called through wrapping
emergency_shell(), with two simple internal knobs (type and error
message). wait_for_loginit() was moved to the lib as well.

2) shell job control fixups

Terminal (the one provided to command line) is thoroughly checked if it
really is terminal. In case of any problems we fallback to /dev/tty1
(if --ctty was used) or if it doesn't exist for whatever reason (or no
--ctty was used), to /dev/console. Additionally, shell is never spawned
through setsid on /dev/console (little point to do so).

This should cover all possible corner cases.
---
 modules.d/99base/dracut-lib.sh |   98 ++++++++++++++++++++++++++++++++++++++++
 modules.d/99base/init          |   64 --------------------------
 modules.d/99shutdown/shutdown  |   37 ++-------------
 3 files changed, 102 insertions(+), 97 deletions(-)

diff --git a/modules.d/99base/dracut-lib.sh b/modules.d/99base/dracut-lib.sh
index cf5aae6..ff80eda 100755
--- a/modules.d/99base/dracut-lib.sh
+++ b/modules.d/99base/dracut-lib.sh
@@ -555,3 +555,101 @@ usable_root() {
     [ -e "$1/lib" -o -e "$1/lib64" ] || return 1
     return 0
 }
+
+wait_for_loginit()
+{
+    set +x
+    [ "$RD_DEBUG" = "yes" ] || return
+    [ -e /run/initramfs/loginit.pipe ] || return
+    echo "DRACUT_LOG_END"
+    exec 0<>/dev/console 1<>/dev/console 2<>/dev/console
+    # wait for loginit
+    i=0
+    while [ $i -lt 10 ]; do
+        if [ ! -e /run/initramfs/loginit.pipe ]; then
+            j=$(jobs)
+            [ -z "$j" ] && break
+            [ -z "${j##*Running*}" ] || break
+        fi
+        sleep 0.1
+        i=$(($i+1))
+    done
+
+    if [ $i -eq 10 ]; then
+        kill %1 >/dev/null 2>&1
+        kill $(while read line;do echo $line;done</run/initramfs/loginit.pid)
+    fi
+
+    set -x
+    rm -f /run/initramfs/loginit.pipe /run/initramfs/loginit.pid
+}
+
+# meant only to be called through emergency_shell wrapper function;
+# standard version is defined below, shutdown override is in
+# 99shutdown/shutdown
+#
+# $1     - 's' or 'i', depending if it was called from shutdown or init
+# $2     - error message
+# $3     - "name", or:
+# $3, $4 - "-n" "name"
+# remaining arguments - remaining message passed to wrapper
+#
+emergency_shell_core()
+{
+    local _type; local _mesg
+    set +e
+
+    _type="$1"; _mesg="$2"; shift 2
+    if [ "$1" = "-n" ]; then
+        _rdshell_name=$2
+        shift 2
+    else
+        _rdshell_name=dracut
+    fi
+    echo ; echo
+    warn "$*"
+    echo
+    if [ $_type = i ]; then
+        source_hook emergency
+        wait_for_loginit
+        [ -e /run/initramfs/.die ] && exit 1
+    else
+        source_hook shutdown-emergency
+    fi
+    if getargbool 1 rd.shell -y rdshell || getarg rd.break rdbreak; then
+        local _tty; local _tmp
+
+        _tty=/dev/console
+        if type setsid >/dev/null 2>&1; then
+            [ -c /dev/tty1 ] && _tty=/dev/tty1
+            _tmp="$(getarg rd.ctty=)" && _tmp="/dev/${_tmp##*/}"
+            if [ -c "$_tmp" ] && exec 9<>$_tmp >/dev/null 2>&1; then
+                [ -t 9 ] && _tty=$_tmp
+                exec 9>&-
+            fi
+        fi
+        [ -x /lib/udev/console_init ] && /lib/udev/console_init $_tty
+
+        echo "Dropping to debug shell."
+        echo
+        export PS1="$_rdshell_name:\${PWD}# "
+        [ -e /.profile ] || >/.profile
+        if [ $_tty != /dev/console ]; then
+            setsid sh -i -l 0<$_tty 1>$_tty 2>&1
+        else
+            sh -i -l 0<$_tty 1>$_tty 2>&1
+        fi
+    else
+        [ $_type = s ] && exec /lib/systemd/systemd-shutdown "$@"
+        warn "$_mesg"
+        # cause a kernel panic
+        exit 1
+    fi
+}
+
+emergency_shell()
+{
+    emergency_shell_core i \
+        "Boot has failed. To debug this issue add \"rd.shell\" to the kernel command line." \
+        "$@"
+}
diff --git a/modules.d/99base/init b/modules.d/99base/init
index 3da6abd..16ed3fc 100755
--- a/modules.d/99base/init
+++ b/modules.d/99base/init
@@ -10,70 +10,6 @@
 
 export -p > /tmp/export.orig
 
-wait_for_loginit()
-{
-    set +x
-    [ "$RD_DEBUG" = "yes" ] || return
-    [ -e /run/initramfs/loginit.pipe ] || return
-    echo "DRACUT_LOG_END"
-    exec 0<>/dev/console 1<>/dev/console 2<>/dev/console
-        # wait for loginit
-    i=0
-    while [ $i -lt 10 ]; do
-        if [ ! -e /run/initramfs/loginit.pipe ]; then
-            j=$(jobs)
-            [ -z "$j" ] && break
-            [ -z "${j##*Running*}" ] || break
-        fi
-        sleep 0.1
-        i=$(($i+1))
-    done
-
-    if [ $i -eq 10 ]; then
-        kill %1 >/dev/null 2>&1
-        kill $(while read line;do echo $line;done</run/initramfs/loginit.pid)
-    fi
-
-    set -x
-    rm -f /run/initramfs/loginit.pipe /run/initramfs/loginit.pid
-}
-
-emergency_shell()
-{
-    local _ctty
-    set +e
-    if [ "$1" = "-n" ]; then
-        _rdshell_name=$2
-        shift 2
-    else
-        _rdshell_name=dracut
-    fi
-    echo ; echo
-    warn $@
-    source_hook emergency
-    echo
-    wait_for_loginit
-    [ -e /run/initramfs/.die ] && exit 1
-    if getargbool 1 rd.shell -y rdshell || getarg rd.break rdbreak; then
-        echo "Dropping to debug shell."
-        echo
-        export PS1="$_rdshell_name:\${PWD}# "
-        [ -e /.profile ] || >/.profile
-        _ctty=/dev/console
-        if type setsid >/dev/null 2>&1; then
-            _ctty="$(getarg rd.ctty=)" && _ctty="/dev/${_ctty##*/}"
-            [ -c "$_ctty" ] || _ctty=/dev/tty1
-            setsid sh -i -l 0<$_ctty 1>$_ctty 2>&1
-        else
-            sh -i -l 0<$_ctty 1>$_ctty 2>&1
-        fi
-    else
-        warn "Boot has failed. To debug this issue add \"rdshell\" to the kernel command line."
-        # cause a kernel panic
-        exit 1
-    fi
-}
-
 trap "emergency_shell Signal caught!" 0
 OLDPATH=$PATH
 PATH=/usr/sbin:/usr/bin:/sbin:/bin
diff --git a/modules.d/99shutdown/shutdown b/modules.d/99shutdown/shutdown
index 21bb37f..8a44e8f 100755
--- a/modules.d/99shutdown/shutdown
+++ b/modules.d/99shutdown/shutdown
@@ -7,44 +7,15 @@
 # Copyright 2011, Red Hat, Inc.
 # Harald Hoyer <harald-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
 
-#!/bin/sh
 . /lib/dracut-lib.sh
 export TERM=linux
 
+# override standard function
 emergency_shell()
 {
-    local _ctty
-    set +e
-    if [ "$1" = "-n" ]; then
-        _rdshell_name=$2
-        shift 2
-    else
-        _rdshell_name=dracut
-    fi
-    echo ; echo
-    warn $@
-    source_hook shutdown-emergency
-    echo
-    if getargbool 1 rd.shell -y rdshell || getarg rd.break rdbreak; then
-        [ -x /lib/udev/console_init ] && /lib/udev/console_init /dev/console
-        echo "Dropping to debug shell."
-        echo
-        export PS1="$_rdshell_name:\${PWD}# "
-        [ -e /.profile ] || >/.profile
-        _ctty=/dev/console
-        if type setsid >/dev/null 2>&1; then
-            _ctty="$(getarg rd.ctty=)" && _ctty="/dev/${_ctty##*/}"
-            [ -c "$_ctty" ] || _ctty=/dev/tty1
-            setsid sh -i -l 0<$_ctty 1>$_ctty 2>&1
-        else
-            sh -i -l 0<$_ctty 1>$_ctty 2>&1
-        fi
-    else
-        exec /lib/systemd/systemd-shutdown "$@"
-        warn "Shutdown has failed. To debug this issue add \"rdshell\" to the kernel command line."
-        # cause a kernel panic
-        exit 1
-    fi
+    emergency_shell_core s \
+        "Shutdown has failed. To debug this issue add \"rd.shell\" to the kernel command line." \
+        "$@"
 }
 
 trap "emergency_shell Signal caught!" 0
-- 
1.7.5.3

[PATCH 10/10] optional shell job control - add documentation

[Michal Soltys]

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 dracut.8.xml        |    9 +++++++++
 dracut.kernel.7.xml |   14 ++++++++++++++
 2 files changed, 23 insertions(+), 0 deletions(-)

diff --git a/dracut.8.xml b/dracut.8.xml
index d4689ee..8947780 100644
--- a/dracut.8.xml
+++ b/dracut.8.xml
@@ -297,6 +297,15 @@ include in the generic initramfs. This parameter can be specified multiple times
         </varlistentry>
         <varlistentry>
           <term>
+            <option>--ctty</option>
+          </term>
+          <listitem>
+            <para>if possible, try to spawn an emergency shell on a terminal
+              with job control</para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
+          <term>
             <option>-h</option>
           </term>
           <term>
diff --git a/dracut.kernel.7.xml b/dracut.kernel.7.xml
index 0571031..08f1838 100644
--- a/dracut.kernel.7.xml
+++ b/dracut.kernel.7.xml
@@ -109,6 +109,20 @@ This parameter can be specified multiple times.</para>
 	    <para>force loading kernel module &lt;drivername&gt; after all automatic loading modules have been loaded. This parameter can be specified multiple times.</para>
           </listitem>
         </varlistentry>
+        <varlistentry>
+          <term>
+            <envar>rd.ctty=<replaceable>&lt;terminal&gt;</replaceable></envar>
+          </term>
+          <listitem>
+            <para>
+              if the dracut image was generated with --ctty option, try to
+              spawn an emergency shell on the specified terminal; if
+              <envar>rd.ctty</envar> is specified without a value or not
+              provided at all, the default is /dev/tty1. The '/dev' prefix
+              can be omitted.
+            </para>
+          </listitem>
+        </varlistentry>
       </variablelist>
     </refsect2>
     <refsect2 id="dracut-kernel-debug">
-- 
1.7.5.3

[PATCH 11/10] dracut: sewing fixup

[Michal Soltys]

We accidentally tried to make upwards symlinks when directories existed.

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 dracut |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/dracut b/dracut
index 4cfcab8..72af2c0 100755
--- a/dracut
+++ b/dracut
@@ -543,7 +543,9 @@ else
 fi
 # initial sewing pass
 for d in "${initdir}${imgdir}"/*; do
-    ln -sfn "${imgdir#/}/${d##*/}" "${initdir}/${d##*/}"
+    if [[ ! -e "${initdir}/${d##*/}" ]]; then
+        ln -sfn "${imgdir#/}/${d##*/}" "${initdir}/${d##*/}"
+    fi
 done
 
 # check all our modules to see if they should be sourced.
@@ -684,7 +686,7 @@ for d in "${initdir}${imgdir}"/*; do
             dfatal "dracut: symlink mismatch ${d##*/} -/-> ${d#${initdir}/}"
             exit 1
         fi
-    else
+    elif [[ ! -e ${s} ]]; then
         ln -sfn "${d#${initdir}/}" "${s}"
     fi
 done
-- 
1.7.5.3

Re: [PATCH 00/10] All recent patches linearly

[Michal Soltys]

Should I redo the set against latest HEAD ? There're few (trivial) 
conflicts regarding first patch after latest upstream updates, and some 
of the patches below were applied already. I have tiny one-liner patch 
to add as well.

Everything is well tested at this point, at least I haven't experienced 
any misbehaviour - both regarding /run treatment or ctty functionality.

[PATCH] init: /dev/.initramfs symlink fixup

[Michal Soltys]

It's not related to $PREFIX being set or not (anymore).

Signed-off-by: Michal Soltys <soltys-R61QfzASbfY@public.gmane.org>
---
 modules.d/99base/init |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/modules.d/99base/init b/modules.d/99base/init
index c109ae4..0ce8ed8 100755
--- a/modules.d/99base/init
+++ b/modules.d/99base/init
@@ -380,7 +380,7 @@ if [ -d "$NEWROOT/run" ]; then
 else
     NEWRUN=/dev/.run
     mkdir -p -m 0755 "$NEWRUN"
-    [ -n "$PREFIX" ] && ln -sfn .run/initramfs /dev/.initramfs
+    ln -sfn .run/initramfs /dev/.initramfs
     # if initramfs's udev uses /run by default, but the host is
     # still /run-less, we should copy udev's data to legacy
     # /dev/.udev, so the necessary info is available for the host
-- 
1.7.7.1

[PATCH 13/10] features: RUNDIR, imgdir, ... [update 2]

[Michal Soltys]

- don't use cp -t (due to busybox's cp)
- add intermediate link to image's tree, to simplify life in init;
  this allows us to switch whole image tree with single 'ln' manipulation,
  instead of going in loop through all /bin, /sbin, ... symlinks;
  we employ that early (see the next point) and before /run move (to not
  lose access to binaries)
- create $prefix (and $prefix_mnt) early, so everything is de-facto
  started from /run/$prefix
- keep /tmp and /var/tmp inside image tree
- simplify det_lib_paths() - make it essentially the same as before
  an earlier patch, but keep it as a separate function
- add a few comments and corner cases fixups

---
 dracut                           |   31 ++++++++++--------
 dracut-functions                 |   29 ++++++----------
 modules.d/99base/init            |   64 ++++++++++++++++++++++---------------
 modules.d/99base/module-setup.sh |    2 +-
 4 files changed, 67 insertions(+), 59 deletions(-)

diff --git a/dracut b/dracut
index 72af2c0..e26e0c3 100755
--- a/dracut
+++ b/dracut
@@ -502,7 +502,7 @@ readonly initdir=$(mktemp --tmpdir=/var/tmp/ -d -t initramfs.XXXXXX)
     dfatal "mktemp failed."
     exit 1
 }
-readonly imgdir=/_img newroot=/sysroot
+readonly imgdir=/_img imglnk=/__img newroot=/sysroot
 
 # clean up after ourselves no matter how we die.
 trap 'ret=$?;[[ $keep ]] && echo "Not removing $initdir." >&2 || rm -rf "$initdir";exit $ret;' EXIT
@@ -517,34 +517,38 @@ export initdir dracutbasedir dracutmodules drivers \
     add_drivers mdadmconf lvmconf filesystems \
     use_fstab libdir usrlibdir fscks nofscks cttyhack \
     stdloglvl sysloglvl fileloglvl kmsgloglvl logfile \
-    debug imgdir prefix prefix_mnt newroot
+    debug imgdir imglnk prefix prefix_mnt newroot
 
 # initial directory layout + host safe symlinks
 if [[ $kernel_only != yes ]]; then
-    for d in /{bin,sbin,etc,lib{,64},var,usr{,/{bin,sbin,lib{,64}}}}; do
+    # directories inside ${initdir}${imgdir}
+    for d in /{bin,sbin,etc,lib{64,},var{,/tmp},usr{,/{bin,sbin,lib{64,}}},tmp}; do
         if [[ -h $d ]]; then inst_symlink $d
         elif [[ -d $d ]]; then inst_dir $d; fi
     done
 
+    # directories inside ${initdir}
     mkdir -m 0755 -p \
-        "${initdir}"/{dev,proc,sys,${newroot#/},root,run{,/{lock,initramfs}},tmp}
+        "${initdir}"/{dev,proc,sys,run{,/{lock,initramfs}},root,${newroot#/}}
 
     # host safe symlinks (will be adjusted later), needed during inst*() calls
-    ln -sfn "${initdir}"/tmp      "${initdir}${imgdir}"/tmp
-    ln -sfn "${initdir}"/tmp      "${initdir}${imgdir}"/var/tmp
     ln -sfn "${initdir}"/run      "${initdir}${imgdir}"/run
     ln -sfn "${initdir}"/run      "${initdir}${imgdir}"/var/run
     ln -sfn "${initdir}"/run/lock "${initdir}${imgdir}"/var/lock
 else
-    for d in /lib{,64}; do
+    for d in /lib{64,}; do
         if [[ -h $d ]]; then inst_symlink $d
         elif [[ -d $d ]]; then inst_dir $d; fi
     done
 fi
+
 # initial sewing pass
+# go through intermediate symlink (${imglnk}) - this greatly simplifies our life
+# inside init
+ln -sfn "${imgdir#/}" "${initdir}${imglnk}"
 for d in "${initdir}${imgdir}"/*; do
     if [[ ! -e "${initdir}/${d##*/}" ]]; then
-        ln -sfn "${imgdir#/}/${d##*/}" "${initdir}/${d##*/}"
+        ln -sfn "${imglnk#/}/${d##*/}" "${initdir}/${d##*/}"
     fi
 done
 
@@ -669,11 +673,10 @@ if strstr "$modules_loaded" " fips " && command -v prelink >/dev/null; then
 fi
 
 # final sewing pass
-# remove helper /run & /tmp links, set symlinks to match initramfs's root, link
+# remove helper /run link, set symlinks to match initramfs's root, link
 # remaining directories (if any)
 if [[ $kernel_only != yes ]]; then
-    rm -f             "${initdir}${imgdir}"/{run,tmp}
-    ln -sfn /tmp      "${initdir}${imgdir}"/var/tmp
+    rm -f             "${initdir}${imgdir}"/run
     ln -sfn /run      "${initdir}${imgdir}"/var/run
     ln -sfn /run/lock "${initdir}${imgdir}"/var/lock
 fi
@@ -682,12 +685,12 @@ for d in "${initdir}${imgdir}"/*; do
     if [[ -h ${s} ]]; then
         # verify if everything is fine
         t=$(readlink "${s}")
-        if [[ $t != ${d#${initdir}/} ]]; then
-            dfatal "dracut: symlink mismatch ${d##*/} -/-> ${d#${initdir}/}"
+        if [[ $t != ${imglnk#/}/${d##*/} ]]; then
+            dfatal "dracut: symlink mismatch ${d##*/} -/-> ${imglnk#/}/${d##*/}"
             exit 1
         fi
     elif [[ ! -e ${s} ]]; then
-        ln -sfn "${d#${initdir}/}" "${s}"
+        ln -sfn "${imglnk#/}/${d##*/}" "${s}"
     fi
 done
 
diff --git a/dracut-functions b/dracut-functions
index 7b6aa5a..0298585 100755
--- a/dracut-functions
+++ b/dracut-functions
@@ -959,23 +959,16 @@ instmods() {
     return $?
 }
 
-# determine lib paths in specified prefix
-# if they point to the same, ignore the one that is a symlink
-# prefer lib64 over lib
+# determine lib paths in specified prefix ($1)
+# order of preference: lib64, lib, lib32
 function det_lib_paths() {
-    local _lib _d _d64
-    _d=$(readlink -e "$1/lib")
-    _d64=$(readlink -e "$1/lib64")
-    if [[ $_d = $_d64 ]]; then
-        [[ -h $1/lib ]] && unset _d
-        [[ -h $1/lib64 ]] && unset _d64
-    fi
-    if [[ -n $_d64 ]]; then
-        _lib=$1/lib64
-    elif [[ -n $_d ]]; then
-        _lib=$1/lib
-    else
-        return 1
-    fi
-    echo "$_lib"
+    local _lib
+
+    for _lib in "$1"/lib{64,}; do
+        if [[ -d $_lib ]]; then
+            echo "$_lib"
+            return 0
+        fi
+    done
+    return 1
 }
diff --git a/modules.d/99base/init b/modules.d/99base/init
index 0397e36..00fcc27 100755
--- a/modules.d/99base/init
+++ b/modules.d/99base/init
@@ -81,20 +81,44 @@ mount $_fs $_opt tmpfs /dev/shm >/dev/null 2>&1
 # Prepare proper tmpfs mount for /run:
 # - /run is just a symlink to real staging area. This allows us to be
 #   independent from any mount place, with trivial symlink manipulation
-# - checking if /run is premounted, is pretty crazy in initramfs ...
-
+# - it handles both: if /run is present with content and/or if it's mounted
 _opt="-o mode=0755,nosuid,nodev,exec"; _fs="-t tmpfs"
 RUNDIR=/_run
 ismounted /run && { _opt="$_opt,remount"; unset _fs; }
-mkdir -m 0755 -p $RUNDIR
+mkdir -m 0755 -p "$RUNDIR"
 # move + remount or mount
-[ -z "$_fs" ] && mount --move /run $RUNDIR
-mount $_fs $_opt tmpfs $RUNDIR >/dev/null 2>&1
+[ -z "$_fs" ] && mount --move /run "$RUNDIR"
+mount $_fs $_opt tmpfs "$RUNDIR" >/dev/null 2>&1
 # copy if mount
-[ -z "$_fs" ] || { cd /run; cp -a -t $RUNDIR .; cd /; }
+[ -n "$_fs" ] && { cd /run; cp -a . "$RUNDIR"; cd /; }
 # set symlink
 rm -rf /run
-ln -sfn ${RUNDIR#/} /run
+ln -sfn "${RUNDIR#/}" /run
+
+# Prepare (if applicable) image tree inside $PREFIX under /run; we do it
+# here, as we want to run everything de-facto from /run/$PREFIX/...
+if [ -n "$PREFIX" ]; then
+    mkdir -p -m 0755 "/run/.prefix"
+    cd "$IMGLNK"
+    cp -a . "/run/.prefix"
+    if [ -d "/run/$PREFIX" ]; then
+        cd "/run/$PREFIX"; cp -a . "/run/.prefix"; cd /
+        umount "/run/$PREFIX" >/dev/null 2>&1
+        rm -rf "/run/$PREFIX"
+    fi
+    if [ -n "$PREFIX_MNT" ]; then
+        mkdir -p -m 0755 "/run/$PREFIX"
+        mount -t tmpfs -o mode=0755,nosuid,nodev,exec tmpfs "/run/$PREFIX"
+        cd "/run/.prefix"; cp -a . "/run/$PREFIX"; cd /
+        rm -rf "/run/.prefix"
+    else
+        _tgt="/run/$PREFIX"
+        mkdir -p -m 0755 "${_tgt%/*}"
+        mv "/run/.prefix" "$_tgt"
+    fi
+    # switch intermediary link to the image tree we actually want to use
+    ln -sfn "run/$PREFIX" "$IMGLNK"
+fi
 
 UDEVVERSION=$(udevadm --version)
 if [ $UDEVVERSION -gt 166 ]; then
@@ -374,7 +398,7 @@ else
 fi
 [ "$RD_DEBUG" = "yes" ] && set -x
 
-# /run move, udev adjustment (if applicable), prefix handling
+# /run move, udev adjustment (if applicable)
 if [ -d "$NEWROOT/run" ]; then
     NEWRUN="$NEWROOT/run"
 else
@@ -388,30 +412,18 @@ else
     if [ -d /run/udev/data -o -d /run/udev/db ]; then
         mkdir -p -m 0755 /dev/.udev
         cd /run/udev
-        cp -a -t /dev/.udev .
+        cp -a . /dev/.udev
         cd /
         rm -rf /run/udev
     fi
 fi
 
-mount --move "$RUNDIR" "$NEWRUN"
+# if we earlier moved away from IMGDIR, go back to it - or we lose access to
+# binaries briefly
+[ -n "$PREFIX" ] && ln -sfn "${IMGDIR#/}" "$IMGLNK"
 ln -sfn "${NEWRUN#/}" /run
-
-if [ -n "$PREFIX" ]; then
-    if [ -d "$NEWRUN/$PREFIX" ]; then
-        [ -n "$PREFIX_MNT" ] &&
-            warn "'$NEWRUN/$PREFIX' already exists, dracut files will be copied directly to this directory"
-        unset PREFIX_MNT
-    else
-        mkdir -p -m 0755 "$NEWRUN/$PREFIX"
-    fi
-    if [ -n "$PREFIX_MNT" ]; then
-        mount -t tmpfs -o mode=0755,nosuid,nodev,exec tmpfs "$NEWRUN/$PREFIX"
-    fi
-    cd "$IMGDIR"
-    cp -a -t "$NEWRUN/$PREFIX" .
-    cd /
-fi
+mount --move "$RUNDIR" "$NEWRUN"
+[ -n "$PREFIX" ] && ln -sfn "${NEWRUN#/}/$PREFIX" "$IMGLNK"
 
 wait_for_loginit
 
diff --git a/modules.d/99base/module-setup.sh b/modules.d/99base/module-setup.sh
index 4c64bca..2a59699 100755
--- a/modules.d/99base/module-setup.sh
+++ b/modules.d/99base/module-setup.sh
@@ -41,7 +41,7 @@ install() {
     [ -x /lib/systemd/systemd-timestamp ] && inst /lib/systemd/systemd-timestamp
 
     # export certain settings to init
-    for _d in newroot imgdir prefix prefix_mnt; do
+    for _d in newroot imgdir imglnk prefix prefix_mnt; do
         _x=$(echo $_d | tr "a-z" "A-Z")
         [ -n "$_d" ] && echo "${_x}=${!_d}" >>${initdir}/etc/dracut-init.conf
     done
-- 
1.7.7.1