When you are running vm in virtual box, and try to start any vm in openstack. The vm that are running in virtualbox will crash immediately, you need to do the follow command to shut it down. If you want to restart that VM, please rmmod the kvm module.
vboxmanage controlvm "your vm name" power off
I guess is that the kvm mod try to take over the hypervisor of virtualbox, so the virtual box crash
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