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[Seth Forshee <seth.forshee+lp@xxxxxxxxxxxxx>]

I'm seeing a direct correlation here between the symptom and the kernel
emitting uevents. For example, in the host run:

 $ udevadm --monitor

And in another terminal in the host run:

 # losetup /dev/loop0 foo

This causes the symptoms even though it has no direct impact on the
container, but does generate a uevent. I've seen the same thing
consistently so far - any command I run which causes a uevent to be
generated also results in processes in the container being killed. You
can also observe that fuse mount command cause uevents to be generated.

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https://bugs.launchpad.net/bugs/1530617

Title:
  FUSE in wily image with upstart installed causes chaos

Status in linux package in Ubuntu:
  Incomplete
Status in lxc package in Ubuntu:
  Confirmed
Status in upstart package in Ubuntu:
  New

Bug description:
  Host:
  DISTRIB_ID=Ubuntu
  DISTRIB_RELEASE=15.10
  DISTRIB_CODENAME=wily
  DISTRIB_DESCRIPTION="Ubuntu 15.10"

  lxc version: 1.1.4-0ubuntu1

  In a LXC container running Ubuntu 15.10, install upstart-sysv to
  replace systemd. Using FUSE then causes almost all processes in the
  container to be killed.

  The following steps reproduce the problem using sshfs:

  # create a wily container and attach to it
  sudo lxc-create -t download -n wily -- -d ubuntu -r wily -a amd64
  sudo lxc-start -n wily
  sudo lxc-attach -n wily

  # inside the container, install upstart-sysv and reboot
  apt-get update && apt-get -y install upstart-sysv
  reboot

  # on the host, reattach to the container
  sudo lxc-attach -n wily

  # back in the container, install ssh and sshfs
  apt-get -y install openssh-server sshfs

  # create an ssh key pair in /root/.ssh
  ssh-keygen

  # set up passwordless ssh
  mkdir ~ubuntu/.ssh
  cat /root/.ssh/id_rsa.pub >> ~ubuntu/.ssh/authorized_keys
  eval $(ssh-agent)
  ssh-add /root/.ssh/id_rsa

  # take a note of the running processes and their PIDs
  ps axjf

  # run sshfs
  mkdir /fuse
  sshfs ubuntu@localhost:/ /fuse

  # we are kicked out of the container
  # run ps again in the container
  sudo lxc-attach -n wily -- ps axjf

  # a whole bunch of processes are now gone. the getty processes now
  have new PIDs, indicating they have been restarted.

  
  Other debugging performed:
  - On a 14.10 host with lxc version 1.1.0~alpha2-0ubuntu3.3, the problem does not occur. FUSE works fine.
  - On the same 14.10 host with lxc upgraded to 1.1.5-0ubuntu3~ubuntu14.04.1, the problem occurs.
  - On a 15.10 host, when running a wily container without upstart, the problem does not occur.
  - On a 15.10 host, when running a trusty container, the problem does not occur.
  - The problem can't be reproduced outside a container (15.10 host, install upstart-sysv, then use FUSE)

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