Re: Questions about the device driver framework

[Vittore Scolari]

markus kaarn wrote:

> Vittore Scolari wrote:
>
> > How a bus driver serve and trust device drivers?
>
>
> Whom bus-driver trust?
> Maybe super-user is one who loads drivers. In monolithic
> kernels i.e. linux, only root can load & unload drivers, because
> he's the one who's trusted. If malicious driver is loaded, it can
> crash whole system down. So, root must know what device-drivers
> he uses to load.
>
> Here i can't see how diferent it can be on u-kernels.
> If say everybody can load device-drivers mm.. it's imposible. 0_0
> So what is system related - loads device-drivers.. super-user does that.
> And users can do everything else.
Yes, i tought it too. But how the bus-driver recognizes a task as a 
ddf-driver, knows that root loaded it and give it permissions on devices?
Supposed that the ddf system isn't integrated with the rest of the hurd, 
capabilities, etc..

Maybe throug the deva layer (that provides interfaces to task-server)? 
Am i wrong?


I think also that on every os drivers integrate togheter. so again, 
drivers need to have a some sort of facility to understand if an IPC 
comes from a driver or from a normal task.
If the IPC comes from a drivers, it should be trusted because it's root 
that loaded it.


Hey, why hurd-l4 can't let the user load a driver?
it would be useful


thanks, Vittore