Some CD-ROM types are bootable in theory, but unsupported by the CD. Examples:
- PCMCIA drives
- Drives connected to SCSI controllers that require firmware
We need to document unfixable cases.
Since booting from PCMCIA and having the possibility of CIS updates (needed for some Ethernet cards) conflict (because non-modular firmware loader cannot work), booting from PCMCIA will not be supported.
As for SCSI controllers that require firmware, the reason for their non-support is that, with the current initramfs structure with static device nodes, binary /init and no udev, it is impossible to load firmware at boot time.