Comment 2 for bug 1086612

Looks like this is caused by the lack of any plymouth themes in the default lxc environment. Installing the plymouth-theme-ubuntu-text package, the following works:

# service tty2 stop
tty2 stop/waiting
# plymouthd --mode=boot --attach-to-session --tty=/dev/tty2
# plymouth show-splash
#

connecting to tty2 with 'lxc-console -n p1 -t 2' shows me the expected text splash screen.

# plymouth ask-for-password --prompt 'open sesame: '
#

the prompt is shown.

So either lxc should mask the 'splash' argument in /proc/cmdline by default, or plymouth-theme-ubuntu-text should be included.

The other problem is that by default, plymouth in Ubuntu looks to /dev/tty7, which isn't mapped anywhere usable under lxc. This could also be forced by forcing an alternate kernel commandline, such as 'console=/dev/lxc/console'.

If /proc/cmdline itself isn't virtualized, I'd be ok with a patch to /etc/init/plymouth.conf to pass an appropriate --kernel-command-line argument when in a container, provided it can be done in the same way as /etc/init/container-detect.conf using env vars. (AIUI, there may be a LIBVIRT_LXC_CMDLINE variable for this?)