Comment 3 for bug 1584393

I've reproduced this on GCE also. Here's what ssh.service looks like during the hang (and it looks like the reload hasn't affected it):

$ sudo systemctl status ssh.service
● ssh.service - OpenBSD Secure Shell server
   Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
   Active: active (running) since Thu 2016-06-23 08:32:11 UTC; 6min ago
  Process: 2702 ExecReload=/bin/kill -HUP $MAINPID (code=exited, status=0/SUCCESS)
 Main PID: 1643 (sshd)
    Tasks: 1
   Memory: 3.8M
      CPU: 108ms
   CGroup: /system.slice/ssh.service
           └─1643 /usr/sbin/sshd -D

Jun 23 08:32:11 xenial-160623-0931 systemd[1]: Started OpenBSD Secure Shell server.
Jun 23 08:32:17 xenial-160623-0931 sshd[1747]: Accepted publickey for ubuntu from 86.179.225.58 port 46404 ssh2: RSA SHA256:HRlolnELGM4aMQXejVDjc0kWktid481/BsLIHtc7Tv0
Jun 23 08:32:17 xenial-160623-0931 sshd[1747]: pam_unix(sshd:session): session opened for user ubuntu by (uid=0)
Jun 23 08:37:17 xenial-160623-0931 systemd[1]: Reloading OpenBSD Secure Shell server.
Jun 23 08:37:17 xenial-160623-0931 sshd[1643]: Received SIGHUP; restarting.
Jun 23 08:37:17 xenial-160623-0931 systemd[1]: Reloaded OpenBSD Secure Shell server.
Jun 23 08:37:17 xenial-160623-0931 sshd[1643]: Server listening on 0.0.0.0 port 22.
Jun 23 08:37:17 xenial-160623-0931 sshd[1643]: Server listening on :: port 22.
Jun 23 08:37:22 xenial-160623-0931 sshd[3134]: Accepted publickey for ubuntu from 86.179.225.58 port 46520 ssh2: RSA SHA256:HRlolnELGM4aMQXejVDjc0kWktid481/BsLIHtc7Tv0
Jun 23 08:37:22 xenial-160623-0931 sshd[3134]: pam_unix(sshd:session): session opened for user ubuntu by (uid=0)