ubuntu-touch-session needs to be able to start even if the homedir is filled to 100%

could you please attach the output of:

adb shell df -h

for when this happens ... it seems that this is solely related to the homedir (unlike bug 1270248)

Reported on utopic r2/ Nexus 4

root@ubuntu-phablet:~# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/loop0 2.0G 1.5G 415M 78% /
udev 916M 4.0K 916M 1% /dev
tmpfs 184M 632K 183M 1% /run
/dev/mmcblk0p23 5.7G 5.4G 8.0K 100% /home
/dev/loop1 106M 104M 1.5M 99% /lib/modules
none 4.0K 0 4.0K 0% /android
tmpfs 184M 632K 183M 1% /run
tmpfs 918M 4.0K 918M 1% /etc/fstab
tmpfs 918M 952K 917M 1% /var/lib/lxc/android/rootfs
/dev/disk/by-partlabel/cache 552M 9.9M 542M 2% /android/cache
/dev/disk/by-partlabel/persist 16M 4.2M 12M 27% /android/persist
/dev/disk/by-partlabel/modem 64M 54M 11M 83% /android/firmware
none 4.0K 0 4.0K 0% /sys/fs/cgroup
tmpfs 918M 0 918M 0% /tmp
none 5.0M 0 5.0M 0% /run/lock
none 918M 0 918M 0% /run/shm
none 100M 4.0K 100M 1% /run/user
tmpfs 918M 0 918M 0% /var/lib/lightdm
tmpfs 918M 0 918M 0% /var/lib/sudo
udev 916M 4.0K 916M 1% /var/lib/lxc/android/rootfs/socket
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/aboot
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/boot
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/misc
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/radio
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/recovery
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/rpm
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/sbl1
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/sbl2
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/sbl3
none 4.0K 0 4.0K 0% /var/lib/lxc/android/rootfs/tz

Same output as above, but attached so that formatting might survive better.

so after researching this for a day there are several issues with ubuntu-touch-session (and probably other packages too) ...

while we manage to bring up a desktop session on the desktop even when /home is 100% full, all the hackery in ubuntu-touch-session like writing to ~/.bashrc, having modified upstart jobs that expect to be able to write to the users homedir etc will not allow this.

the only option to at least get the session up again (to i.e. show a message to the user to free up space and to still allow emergency calls etc) will be a general re-write of ubuntu-touch-session and the additional changed upstart jobs here to only use XDG_RUNTIME_DIR or /tmp on session startup. i will start this re-write this week, i am not yet sure how we can present a message to the user (a discussion with design is anticipated at the malta sprint) to tell him/her to free up space and i can not make any prediction about the timeframe for fixing this bug (with luck only a few days, but there are system design issues in general here that we need to fix)

on a sidenote our standard testing suite should get a test to boot with a $HOME set to readonly after this bug is fixed so we can make sure this does not regress again.

adding CI service as reminder for adding a test once we have it fixed

with the changes in http://paste.ubuntu.com/7452072/ i can get a unity8 session to start even with a completely readonly home

I just felt the need to point out that unity8 doesn't really even use HUD any more (as of a week or so ago, the gesture to invoke HUD was disabled).

So if HUD failing to load due to DBus failure blocks unity8 startup, we could probably just cut a few more cords in the unty8 codebase to prevent the HUD UI component from attempting to initialise HUD. Either by deleting the UI components, or by ensuring they don't load.

as i understood the removal of the gesture is only temporary until an alternative is found ...
also doesnt the search function in the panel use the HUD as backend still ?

generally i'm just trying to move the dbus-session file to $XDG_RUNTIME_DIR and adjust all consumers to read it from there, the change to the HUD code is a trivial one liner (and you get cleanup of the messed up upstart job (duplicated pre-start script) for free with the MP)

Okay, cool. If you have a more general purpose fix, then awesome. In addition, the deduplication fix is included in an upcoming MR that's being SRU'd to trusty.

This bug was fixed in the package dbus - 1.6.18-0ubuntu11

---------------
dbus (1.6.18-0ubuntu11) 14.09; urgency=medium

  * write to $XDG_RUNTIME_DIR instead of the users home when creating the
    dbus-session file, so we can start our session even with 100% filled or
    readonly home dir (LP: #1316978)
 -- Oliver Grawert <email address hidden> Fri, 26 Sep 2014 14:18:38 +0200

This bug was fixed in the package ubuntu-touch-session - 0.108+14.10.20140926.1-0ubuntu1

---------------
ubuntu-touch-session (0.108+14.10.20140926.1-0ubuntu1) utopic; urgency=low

  [ Oliver Grawert ]
  * 'move to new dbus-session address handling in XDG_RUNTIME_DIR (LP:
    #1316978) (LP: #1316978)
 -- Ubuntu daily release <email address hidden> Fri, 26 Sep 2014 14:45:01 +0000

This bug was fixed in the package dbus - 1.8.8-1ubuntu2

---------------
dbus (1.8.8-1ubuntu2) utopic; urgency=medium

  * write to $XDG_RUNTIME_DIR instead of the users home when creating the
    dbus-session file, so we can start our session even with 100% filled or
    readonly home dir (LP: #1316978)
 -- Oliver Grawert <email address hidden> Fri, 26 Sep 2014 15:07:05 +0200