I had a problem running VirtualBox, and found the solution to this problem (collision with kvm) was to run:
sudo modprobe -r kvm_intel

The only problem is, I have to manually run this each time I boot. I would like this to happen automatically. I poked around /etc/modprobe.d/*.conf but these just seem to effect how the modprobe command works.

So, is there a nice safe way to save me from having to manually remove each time I boot (which is rare enough I'll probably forget the magic command by then)? Any way to do this would be great, but it would be especially nice to know if I can find why and where kvm_intel is coming from, and block it there.

Thanks!

You should be able to blacklist the module in /etc/modprobe.d/blacklist.conf but it's not clear from your post whether you already tried that and it didn't work. To blacklist the module just edit blacklist.conf by adding the following at the end of the file:

kvm_intel

If that doesn't do the job, edit /etc/rc.d/rc.local by adding this line at the end:

modprobe -r kvm_intel

rc.local is useful because it runs with root privileges during boot and is the last init script to run. If something keeps reinserting the module in the init sequence rc.local will clean it up at the end.

I hadn't tried blacklist-ing and it works perfectly. Thank you!

Instead of modifying /etc/modprobe.d/blacklist.conf, you can just add a new file into /etc/modprobe.d/ with the relevant blacklist command. The advantage of this is that /etc/modprobe.d/blacklist.conf is owned by the hwdata rpm and so could get changed on an update or upgrade. You would then have to track down what to modify to get the old behavior back. With a separate file for your own modifications, you will never have to worry about this.