Bug#660983: Licensed Symbol Conflicts with Some Non-GPL Modules

[Jonathan Nieder <jrnieder@gmail.com>]

David Baron wrote:

> Most of the discussion of the -rt seems to be amount linux-audio-users and 
> such. I am not in touch with NC or process control but these will want it 
> also. I believe that they would also be involved with non-gpl software.

Sorry to have veered so far off-topic.  I believe many -rt
applications have programs in userspace talking to hardware (for
example using a serial port).

[...]
> I like nouveau very much but unfortunately, there is no openGL in it.

Depends on your card.
http://nouveau.freedesktop.org/wiki/MesaDrivers

> Switching to nouveau means removing its modprobe blacklist and changing 
> xorg.conf. Simple enough but I would like to be able to do this at boot time, 
> either by command or by uname -r (in this case). Otherwise, this becomes a bit 
> of a pain.

Hm, that sounds like a reasonable request.  Blacklisting a driver in
modprobe.conf does not prevent it being loaded explicitly, and the
nouveau driver in X explicitly runs "modprobe nouveau" if I remember
correctly, so there should be no need to unblacklist nouveau, but
there would still be a need to prevent the nvidia driver from being
loaded and let X know what's going on.

Does DKMS offer a way to build a module only for some kernels?  If so,
perhaps the nvidia X driver could be taught to take care of falling
back to fbdev or vesa when the kernel-side driver is not loaded.

[...]
> One other regression issue though, maybe to file another bug:
> mpu401 module will not load. It is there but says "no such device"
> Loads fine on the non-rt kernel.

Yep, sounds worth a bug.  Be sure to attach full "dmesg" output from
booting a working and non-working kernel when reporting it.

Hope that helps,
Jonathan