I did an "apt-get update; apt-get dist-upgrade" on a multiprocessor xenial amd64 machine, and was not able to replicate this bug.
Linux armv8hello.local.lan 4.4.0-38-generic #57-Ubuntu SMP Wed Sep 7 10:19:14 UTC 2016 aarch64 aarch64 aarch64 GNU/Linux
Ubuntu 16.04
I did an "apt-get update; apt-get dist-upgrade" on a multiprocessor xenial amd64 machine, and was not able to replicate this bug.
Linux armv8hello. local.lan 4.4.0-38-generic #57-Ubuntu SMP Wed Sep 7 10:19:14 UTC 2016 aarch64 aarch64 aarch64 GNU/Linux
Ubuntu 16.04