dracut now has a horribly ugly switchroot implementation whose only good point is that it allows us to get rid of nash. It needs to be replaced by something more flexible as soon as possible, but it works well enough for testing purposes. As usual, this applies on top of my previous patch series. --- TODO | 9 +++------ dracut.spec | 2 -- init | 33 ++++++++++----------------------- modules/90gen-switch_root | 28 ++++++++++++++++++++++++++++ modules/99base | 2 +- switch_root | 3 --- switch_root.in | 30 ++++++++++++++++++++++++++++++ 7 files changed, 72 insertions(+), 35 deletions(-) diff --git a/TODO b/TODO index e04be3a..3ced6f7 100644 --- a/TODO +++ b/TODO @@ -4,12 +4,9 @@ are/should be marked with "FIXME" in the code INITRAMFS TODO -------------- -* Currently, our switch_root command uses nash's switchroot. Getting -a reasonable switchroot implementation into util-linux-ng is a -pre-condition for support on other distros. pjones has a basic -implementation at -http://pjones.fedorapeople.org/mkstart/usr/lib/mkstart/switchroot.c -and I've asked kzak about util-linux inclusion +* We have a horribly ugly switchroot implementation whose only + good point is that it gets rid of our dependency on nash. + It needs to be replaced by something nicer. * The hard-coded list of udev rules that we care about is kind of lame. See about getting /lib/udev/initrules.d or similar for storing the rules that we care about in the initramfs. These could be diff --git a/dracut.spec b/dracut.spec index 24f6513..04590cd 100644 --- a/dracut.spec +++ b/dracut.spec @@ -19,9 +19,7 @@ Requires: findutils Requires: grep Requires: mktemp Requires: mount -Requires: nash Requires: bash -Requires: /usr/bin/eu-readelf Obsoletes: mkinitrd < 7.0 Provides: mkinitrd = 7.0 BuildArch: noarch diff --git a/init b/init index c8ac4e5..69f4b7a 100755 --- a/init +++ b/init @@ -10,13 +10,12 @@ emergency_shell() echo ; echo echo "Bug in initramfs /init detected. Dropping to a shell. Good luck!" echo - sh -i 2>/dev/console + sh -i } getarg() { local o line - read -r line </proc/cmdline - for o in $line; do + for o in $CMDLINE; do [ "${o%%=*}" = "$1" ] && { echo $o; break; } done return 1 @@ -31,20 +30,18 @@ source_all() { echo "Starting initrd..." export PATH=/sbin:/bin:/usr/sbin:/usr/bin export TERM=linux - +CONSOLE=/dev/console +[ -c $CONSOLE ] && exec >$CONSOLE 2>&1 <$CONSOLE trap "emergency_shell" 0 -# /dev/console comes from the built-in initramfs crud in the kernel -# someday, we may need to mkdir /dev first here -# exec > /dev/console 2>&1 < /dev/console - # mount some important things mount -t proc /proc /proc mount -t sysfs /sys /sys mount -t tmpfs -omode=0755 udev /dev +read CMDLINE </proc/cmdline; + # FIXME: what device nodes does plymouth really _need_ ? mknod /dev/ptmx c 5 2 -mknod /dev/console c 5 0 mknod /dev/fb c 29 0 mkdir /dev/pts mount -t devpts -o gid=5,mode=620 /dev/pts /dev/pts @@ -59,7 +56,7 @@ udevd --daemon udevadm trigger >/dev/null 2>&1 # mount the rootfs -NEWROOT="/sysroot" +export NEWROOT="/sysroot" # FIXME: there's got to be a better way ... # it'd be nice if we had a udev rule that just did all of the bits for @@ -85,22 +82,12 @@ echo "Trying to mount rootfs $root" ln -s "$root" /dev/root mount -o ro /dev/root $NEWROOT || emergency_shell -# now we need to prepare to switchroot -mount --bind /dev $NEWROOT/dev - -# FIXME: now for a bunch of boiler-plate mounts. really, we should have -# some like /etc/fstab.sys that's provided by filesystem/initscripts -# and then do mount -f /etc/fstab.sys -a -mount -t proc /proc $NEWROOT/proc -mount -t sysfs /sys $NEWROOT/sys +i=$(getarg init) +[ "$i" ] && export INIT="${i#init=}" source_all pre-pivot -# kill off udev -kill $(pidof udevd) - -# FIXME: nash die die die -exec switch_root +exec switch_root $CMDLINE # davej doesn't like initrd bugs echo "Something went very badly wrong in the initrd. Please " echo "file a bug against mkinitrd." diff --git a/modules/90gen-switch_root b/modules/90gen-switch_root new file mode 100755 index 0000000..0699aed --- /dev/null +++ b/modules/90gen-switch_root @@ -0,0 +1,28 @@ +#!/bin/bash +( + RM=$(find_binary rm) + INIT=$(find_binary init) + CHROOT=$(find_binary chroot) + LIBPATH=":" + for bin in "$RM" "$INIT" "$CHROOT"; do + while read line; do + [[ $line =~ '(([^ ]*/lib[^/]*)/[^ ]*\.so[^ ]*)' ]] || continue + strstr "$LIBPATH" ":/sysroot${BASH_REMATCH[2]}:" || \ + LIBPATH+="/sysroot${BASH_REMATCH[2]}:" + [[ ! $LDSO && ${BASH_REMATCH[1]} = */ld-linux*.so.* ]] && { + LDSO=${BASH_REMATCH[1]} + LIBDIR="${LDSO%/*}" + } + done < <(ldd "$bin") + done + LIBPATH=${LIBPATH%:}; LIBPATH=${LIBPATH#:} + + sed -e "s,[@]RM[@],${RM}," \ + -e "s,[@]INIT[@],${INIT}," \ + -e "s,[@]CHROOT[@],${CHROOT}," \ + -e "s,[@]LIBPATH[@],${LIBPATH}," \ + -e "s,[@]LIBDIR[@],${LIBDIR}," \ + -e "s,[@]LDSO[@],${LDSO}," <"$dsrc/switch_root.in" >"$dsrc/switch_root" + chmod 775 "$dsrc/switch_root" + inst "$dsrc/switch_root" /sbin/switch_root +) diff --git a/modules/99base b/modules/99base index c746abc..e566a19 100755 --- a/modules/99base +++ b/modules/99base @@ -1,5 +1,5 @@ #!/bin/bash -dracut_install mount mknod mkdir modprobe pidof sleep chroot echo sed sh ls +dracut_install mount mknod mkdir modprobe pidof sleep chroot echo sed sh ls umount # install our scripts and hooks inst "$initfile" "/init" diff --git a/switch_root b/switch_root deleted file mode 100755 index 2f0b8fa..0000000 --- a/switch_root +++ /dev/null @@ -1,3 +0,0 @@ -#!/sbin/nash - -nash-switchroot diff --git a/switch_root.in b/switch_root.in new file mode 100755 index 0000000..88548c7 --- /dev/null +++ b/switch_root.in @@ -0,0 +1,30 @@ +#!/bin/sh +LIBDIR="${NEWROOT}@LIBDIR@" +LDSO="${NEWROOT}@LDSO@" +INIT="@INIT@" +CHROOT="${NEWROOT}@CHROOT@" +RM="${NEWROOT}@RM@" +LIB="${LIBDIR##*/}" +LIBPATH="@LIBPATH@" +die() { echo "$1"; exit 1; } +[ -d "$LIBDIR" ] || die "No /lib dir on $NEWROOT, dying horribly." +[ -f "$LDSO" ] || die "No library interpreter on $NEWROOT, dying horribly." +[ -x "$NEWROOT/$INIT" ] || die "No init on $NEWROOT, dying horribly." +[ -x "$CHROOT" ] || die "No chroot on $NEWROOT, dying horribly" +[ -x "$RM" ] || die "No rm on $NEWROOT, dying horribly" +cd / +# kill udevd, move all our mounts over to the new root +kill $(pidof udevd) +mount --move /proc $NEWROOT/proc +mount --move /sys $NEWROOT/sys +mount --move /dev $NEWROOT/dev +# redirect to new console. Our old initramfs will not be freed otherwise +CONSOLE=$NEWROOT/dev/console +[ -c $CONSOLE ] && exec >$CONSOLE 2>&1 <$CONSOLE +# remove everything on the initramfs +for x in *; do + [ "/$x" = "$NEWROOT" ] && continue + LD_LIBRARY_PATH="$LIBDIR" "$LDSO" "$RM" -rf "$x" +done +# start running on the real root filesystem +exec "$LDSO" --library-path "$LIBPATH" "$CHROOT" "$NEWROOT" "$INIT" "$@" -- 1.6.0.6 -- To unsubscribe from this list: send the line "unsubscribe initramfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
