For several years I have run both the Knoppix ISO-image and disk-based versions under kvm for installs, maintenance etc. The basic method works for 8.3 too, but only as far as the first flash install.
Klaus K has made Knoppix more "fool-proof" to run under kvm by restricting it to read-only mode. For many users, that is clearly a feature: You may run your ordinary Knoppix install under kvm so it functions as both host and guest at once, but if persistent store is involved, and the host and the guest instances perform different updates to that, then what?
It is only a question of time until the file system is corrupted - it is easy to imagine that prof. Knopper has introduced this restriction from experiences with broken systems.
The bug is that it doesn't stop there. If you run different copies of Knoppix on different partitions, or run Knoppix under another OS variety, even another version of Knoppix, the only thing to be careful about is that the partition where the persistent store of the VM resides is not writable by other OS'es. But don't try to explain that to Knoppix 8.3. It only checks whether it is run under kvm, and in that case, the system is mounted read-only. Which kind of blocks many important uses of Knoppix images.
While the default behaviour is "correct", there must be a cheatcode for disabling it, e.g. VIRTWRITE. I guess specialists on minirt.gz should not have too much problems rolling their own, but this is a general issue, so for me it belongs in Knopper-land proper.
Vintage Dream Writer NTS 325 Computer Basic Language Notebook “Untested “
$30.00
Vintage Compaq 141649-004 2 Button PS/2 Gray Mouse M-S34 - FAST SHIPPING - NEW
$8.99
Vintage Classic Apple Macintosh System Boot Install Disk Floppy/CD *Pick Version
$10.39
VINTAGE MANUAL IBM / 5340 Volume D Field Service Logics
$74.99
Voltage Blaster (Enhanced) -5V ISA AT ATX Power for Vintage Retro PCs US Seller
$12.95
(2) Vintage MMI 256 x 4 ROM Chips for HP 3000 Minicomputer 1816-0070 1816-0072
$36.00
Vintage Black Microsoft intellimouse Optical USB Wheel Mouse 1.1/1.1a - EXC COND
$28.95
NEW Manufacture OLD STYLE Oval 3 Prong Power Cord HP style 125V 7A 875W Vintage
$39.95
$150.00
Vintage Comfort Keyboard Systems Ergomagic Mechanical AT/PS2 Keyboard
$149.99