After recent updates display and wi-fi is lost

[Liam Proven]

On Fri, 4 Dec 2020 at 15:04, Tuukka Härkönen via ubuntu-users
<ubuntu-users at lists.ubuntu.com> wrote:

> Update. Not sure if you got this already, but I was able to fix the problem by adding kernel headers that were missing. I came across with that solution when browsing about the Virtual Box issue on Ask Ubuntu. Very weird. I have no clue what the "kernel headers" even are and why they can go missing like that after update.
>
> This one solved it:
>
> sudo apt-get install linux-headers-$(uname -r)
>
> Everything worked well after that.
>
> Thank you Liam anyway.

Aha!

So, a different problem then.

GPU drivers have to interact closely with the Linux kernel. Virtualbox
installs a kernel driver too for its virtual networking switch, so
that VMs can communicate with each other, and/or the host, and/or the
public Internet.

For this close interaction, the drivers load into the kernel as
modules. Modules are specific to one specific version of the kernel.
Every time you update the kernel, these driver modules must be
rebuilt. This means they must be linked against the specific kernel
they are running on. A tool called DKMS does this automatically -- if
you don't have it, or don't know, try:

sudo apt install dkms

If it's not there, it will be added. If it is, nothing changes.

To rebuild kernel modules, the `build-essential` package supplies the
needed tools, and you also need the header files for that particular
kernel version.

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