[Pkg-virtualbox-devel] Bug#465597: virtualbox-ose: misleading

[Hilko Bengen]

Michael Meskes <meskes at debian.org> writes:

> On Mon, Feb 18, 2008 at 08:16:01PM +0100, Hilko Bengen wrote:
>> > Silly me, I simply forgot that we have an init script nowadays. When we
>> > started there was none and I don't like the idea of adding one just for
>> > a modprobe. Not sure what the others say, but I'll try to add the modprobe to
>> > the init script for the next upload
>> 
>> Let's make that configurable via a variable in
>> /etc/defaults/virtualbox-ose, please.
>
> Sure, no problem, but would you care to elaborate why?

SUPDrv-linux.c does some pretty *scary* things with kernel/CPU
internals for which the kernel doesn't export interfaces (and probably
for a good reason): It disables the NMI watchdog and manipulates the
Interrupt Descriptor Table and APIC.

Even if these things by themselves don't make the host machine
unstable, we can't be sure that vboxdrv and kernel modules that are
used by other VM won't step on each other's toes and possibly crash
the machine. AFAIK, all full x86 virtualizers need to patch at least
the IDT at some point if they want to achieve some performance.

Cheers,
-Hilko