Vagrant powershell still active even after guest system offline.

[darkn3rd]

After shutting down Windows guest, vagrant powershell still active.

Vagrant version

Vagrant 2.1.2 Virtual Box 5.2.16r123759

Host operating system

Windows 8.1

Guest operating system

Windows 2016

Vagrantfile

Vagrant.configure("2") do |config|
  config.vm.box = "my/windows2016"
end

Expected behavior

vagrant powershell session would terminate.

Actual behavior

vagrant powershell session still active, cannot exit session.

Steps to reproduce

1. vagrant init my/windows2016
2. vagrant up
3. vagrant powershell
4. In Virtual Machine Manager, PowerOff system created by vagrant.

[darkn3rd]

In Japan at the moment, so have no access to Windows host. I can help out with further investigation on this later (after Aug 28).