This is not a kernel problem.
/proc/kcore contains the kernel address space, and that address space
_includes_ any memory-mapped devices (the 640k-1MB range, for example).
As such, uncontrolled access to that file will result in undefined
behaviour (that's partly why the file is only root-readable).
The same thing can happen with /dev/mem and /dev/port.
> 2) The lp driver seems to behave badly when my printer is turned
> on. I'm using an HP DeskJet 540. Basically, when the driver
> is installed (I've seen the same behavior via module or built-in
> support), it will say
>
> lp: Driver configured but no interfaces found.
>
> instead of
>
> lp1 at 0x378 (polling)
>
> In short, the driver only starts correctly if I have the printer
> off when it starts. This is a bug, right? :)
Sounds like a bug. Anybody have an idea about this one?
Linus