apt-get autoremove "Before uninstall, this module version was ACTIVE on this kernel"

When running apt-get autoremove (or dry run with -s switch), what does the following message mean?

Status: Before uninstall, this module version was ACTIVE on this kernel.

And what should I do to diagnose if this is going to be a problem?

Edit: I'm on 13.10 but I think this question is version agnostic?

Solution 1:

It means that it's going to remove a package that contains a kernel module (or version of a kernel module) that's in use by the system. After removing it and rebooting, you won't be able to load that module.

Whether or not that's an issue for you really depends on the module and if you're replacing it with something else. I don't think there's a one-size-fits-all answer for this other than: read the message and work out if that's a problem. If it is, just reinstall that package and move on.

Solution 2:

It can also mean that an upgrade has just been done to your system, and that the version of the module which you are being warned about is actually the old version, running only until the next reboot (at which point it would have been removed anyway).

E.g. I was told that my in-use Broadcom wireless driver was being removed! From looking at the error message (plus a bit of trial and error) I worked out that the command to re-install it was:

sudo dkms install add bcmwl/6.30.223.271+bdcom

But on running this I was told that this driver was already installed, at a newer version than the in-use one which I was being warned about.

It's still almost certainly better not to just ignore this warning. But it's quite possible that a variant of the above command (modified to fit the package you're being warned about) will tell you that a newer version is installed, in which case the above is what is going on, and the warning is nothing to worry about.