I haven’t had much exposure to KVM yet, so over the weekend I decided to check it out on my laptop.  After playing around with it a bit, I needed to power on an instance of VMware Workstation, and the following error popped up on my screen …

The virtualization capability of your processor is already in use.  Disable any other running hypervisors before running VMware Workstation.

Well that makes sense.  So I uninstalled KVM and the issue was resolved … or so I thought.  This morning as I powered on another instance of VMware Workstation, I got the same error again.  Hmmmm.  That was a bit more confusing because, to my knowledge, KVM was completely removed from my system.  Again, so I thought.  But a quick look at the currently loaded kernel modules revealed both the kvm_intel and the kvm modules.

As it turns out, when you remove KVM via apt-get (meaning, this *could* be a debian / ubuntu issue, not sure if other package managers do the same thing), it doesn’t actually completely remove itself.  The kvm and kvm_intel modules not only remain, but they continue to get loaded upon startup.  When I removed the modules, my VMware Workstation powered on without issue.

So then, that voice inside of my head — the one I should NEVER listen to — said “I wonder what happens when you load the KVM modules after you’ve powered on your VM?”  I *knew* it could only lead to bad things, but I couldn’t help myself.  Guess what?  Not only did VMware Workstation completely freeze, but now I can’t power on my VM, no matter what I try.   Grrrr.  I swear, someday I’ll be a news headline that reads … An eyewitness confirms his last words were, “I wonder what this button does?”

Anyway, if you get this error, simply check for the kvm modules (lsmod | grep kvm should do the trick).  Simply removing the modules will fix the issue.