I have an interesting situation for which I have not found an answer,
I've been pondering this for about two weeks.
I have two Nvidia cards: a 960 and a 1060. I am forced to use Ubuntu
16.04 when I would rather use Jessie.
When I install the nvidia driver package for Jessie or the one from
Jessie-backports on Jessie, qemu with VGA passthrough to the 1060 locks
up and does not function.
The same thing happens on Ubuntu 16.04 when installing the prebuilt
package there.
Manually installing the driver on Jessie is the same. However, when I
manually install the driver on 16.04; everything functions as it should.
There is no change in the VM settings. There is no change in the kernel
that would cause the issue. 16.04 uses the exact same kernel in both
cases and the exact same version of the nvidia driver - so it is not a
kernel patch.
It has to be something in the nvidia driver package, that affects both
Jessie and downstream Ubuntu 16.04, causing passthrough to fail and qemu
to lock up.
For the life of me, I can't fathom what it is. The VFIO device nodes
are present, and the card is properly bound - but it is acting like the
card is in a busy state unless I manually install the driver on 16.04.
At this point, I can dig through the file-system looking for some minute
change or I can ask for help.
Any thoughts?
