I see the same behaviour, but I'm not sure if the cause is the same, on
4.4.0-112-generic and 4.4.0-116-generic. In my case, the VM remains
responsive for a variable amount of time. Sometimes it works long enough
to login via SSH, at other times it does not get to the login screen. In
This seems to be a duplicate of
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I'm not sure if this is the cause or a red herring, but I found this on
one of the machines which got stuck on boot. Other instances usually
don't print anything.
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