I used to dual-boot windows, but I was too lazy to actually reboot, so naturally I had Virtualbox just boot the physical Windows partition while Linux was running. Which is totally fine!

It's not a real dual boot if you don't boot both partitions at the same time.

As long as you don't install guest VBox drivers, those would make it hang when it boots as the host on physical hardware, since there's no longer someone above to answer the hypercalls.

> I had Virtualbox just boot the physical Windows partition while Linux was running. Which is totally fine!

I had no idea that this was possible, and I learned something new today. Thank you!

I think Windows refused to do that at some point? So I booted the physical Linux partition from Windows if I needed both at the same time. That's on a laptop that otherwise almost always ran Linux.

Yeah. That is a valid use. I mean, this is how I installed Windows to begin with, from Linux via QEMU, onto my other hard drive. I did reboot and test it out, and it worked just fine.