Comment # 3 on bug 966618 from Michael Andres

This is a packaging issue.

Already installed on the system:
  bbswitch-kmp-default-0.8_k4.4.0_3-24.26.x86_64

  (@System just indicates that the installed version
   is not available in any known repo anymore).

To be installed:
  bbswitch-kmp-default-0.8_k4.4.0_3-24.28.x86_64 from Bumblebee project

Obviously the  bbswitch-kmp is tagged as 'multiversion' install, but the
different versions share common files
(/lib/modules/4.4.0-3-default/updates/bbswitch.ko) with changing content. 

This causes a file conflict as install of one version damages the other.


=============
Most common problem is, that you want multiple bbswitch-kmps (one per installed
kernel version), but actually want to be able to update each kernel specific
kmp to a new release.

This can not be achieved by making the bbswitch-kmp as a whoole 'multiversion'.

You actually need no multiversion at al. You need the kernel version being part
of the kmp name ('bbswitch-kmp-4.4.0-3-default' i.e. 'bbswitch-kmp for kernel
4.4.0-3-default').

This way you have multiple kernel specific bbswitch-kmp-<KERNELTAG> packages.
And each package can be independently updated to a new release (a new
/lib/modules/<KERNELTAG>/updates/bbswitch.ko) without file conflicts.