AlpineLinux: Adjusting Xen VM to run on KVM
Adjust the following items to ensure a successful update.
You need to load additional kernel modules at boot:
Add them to /etc/update-extlinux.conf
Regenerate your initrd
(The boot device can still show your old one, that's not a problem)
Disable the Xen console in inittab
Check that acpid is enabled
Check your /etc/fstab
At the least change your disk paths from xvdN to vdN (Xen Blockfront to VirtIO Block).
If you're a big smarter, change them to mount using LABEL or UUID. That way you need almost no changes to migrate between different hypervisors.
When it's just too late
If you need to do this on a VM that was already migrated and doesn't boot, see how to get your root mounted in single user mode:
You'll also need to add the virtio modules to your command line (like the others there, you'll see it)