Test version of Upstart with full chroot support available

[Clint Byrum]

Excerpts from James Hunt's message of Fri Apr 08 08:51:48 -0700 2011:
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> Hi All,
> 
> As a precursor to pushing this update out to Natty next week, I've
> updated my upstart-testing PPA with Upstart version 0.9.5-1ubuntu1:
> 
>     ppa:jamesodhunt/upstart-testing
> 
> Code is here:
> 
>     lp:~jamesodhunt/ubuntu/natty/upstart/fix-chroot-sessions
> 
> As the name suggests, chroots should now work fully [1], but we are keen
> to solicit feedback from the community.

FYI, on my natty box when I was running this, installing dbus in a schroot
session resulted in upstart consuming all available virtual memory and
eventually crashing the box.

Steps to reproduce:

(assuming you've setup schroots w/ mk-sbuild):

schroot -c natty-amd64 -u root
apt-get install dbus


At the 'setting up dbus' point, upstart starts to consume memory at an
alarming rate.

This is likely because the dbus upstart job has a post-start that sends
USR1 to pid 1, which is supposed to tell it to re-connect to dbus.

I believe the bug is because the USR1 handler needs to ignore requests
to re-connect to dbus from chrooted processes, but I haven't gotten very
deep in to debugging it yet.