> I just recently thought about that (Dosemu died and took my
> console with it).
>
> Would not something like the following be enough to always
> be able to recover?
On well-behaved hardware, sure. Many systems have gross hardware.
> 1. Make the kernel know how to reset the video card to a known state.
You can go from a known state to a known state.
You can go from any state to an unknown state -- useless.
Sorry, you can't get to a known state from an unknown state.
> This should essentially be a string of "output X to register Y";
> a user land application could configure it via some IOCTL.
Yes, it _should_ be. On many boards, it is not.
> (As to the userland configurator, I'd like to see something similar
> to the OS/2 SVGA utility - in a V86 jail, do a video card init
> (and mode switches), and simply record what the BIOS does.
Nice trick, but only useful to get X running on an unknown card.
It won't help you reset a card from some unknown state.