You can get an overview of changes on KernelNewbies.org
If you use VirtualBox, install v6.0.4 or later from the official Oracle PPA. The version available in Ubuntu 18.04 repositories is very outdated (v5.2). VirtualBox 6.0.4 and later versions have support for the 5.0 kernel.
wget -q https://www.virtualbox.org/download/oracle_vbox_2016.asc -O- | sudo apt-key add - echo "deb https://download.virtualbox.org/virtualbox/debian bionic contrib" | sudo tee /etc/apt/sources.list.d/oracle_vbox.list sudo apt update sudo apt install virtualbox-6.0
There seems to be a few issues with the NVIDIA graphics drivers in Ubuntu repositories. You may be stuck on a lower resolution after installing the 5.0 kernel.
Ubuntu 18.04.2 HWE
Ubuntu 18.04.2 was released a few weeks ago with a new Hardware Enablement Stack (HWE). This brings Linux 4.18 and Mesa 18.2.2 to the Ubuntu 18.04 LTS platform.
Existing users can install the HWE stack with the following commands:
sudo apt install --install-recommends linux-generic-hwe-18.04 xserver-xorg-hwe-18.04
Updating Mainline Kernels
There are many security issues that are discovered and fixed daily in the Linux kernel. Fixes are first released in upstream kernels before reaching downstream distributions like Debian and Ubuntu.
If your system is connected to the internet, you need to keep the kernel updated to avoid security risks.
Official Ubuntu kernels can be updated by running a full system update at regular intervals.
Mainline kernels can be updated using Ukuu, or by downloading and installing packages manually. If you are using Ukuu, it is recommended to select the Install Automatically option from Settings, along with Stay on the same series. Staying on the same series ensures that you receive security updates for the installed series, but are not automatically upgraded to the next series (which may cause problems).
You need to install updates only for the kernel series that you are currently running. There is no need to move to the next series for sake of security.
For example, if you are running Linux 4.20 you need to install the latest update for that series (currently 4.20.13) in order to stay secure. These are called point updates and contain security patches and bug-fixes that are back-ported from the latest series (currently 5.0).
Every series receives security patches and bug-fixes for a couple of years after the initial release. Once it reaches End-of-life it will stop receiving updates and you should consider moving to the next series in order to stay secure.
A Long-term series (LTS) receives security updates for 6 years compared to one or two years for a normal series. Linux 4.19 for example, is an LTS series and will receive updates till 2022. Linux 4.20 is not LTS and will stop receiving security updates after next year. When that happens, you need to move to the next series to stay secure.
Skipping Updates for Official Kernels
This tip is for people who are using mainline kernels and wish to skip updates for official kernels.
If you use Ukuu to install mainline kernels on your system, you can skip updates for any official kernels that are installed. This will save some time and bandwidth during system updates.
This can be done using the apt-mark hold command which will “freeze” or hold back updates for specified packages.
sudo apt-mark hold linux-generic linux-image-generic linux-headers-generic
The next time you run a full system update, all packages will be updated, except the packages that you have put on hold.
You can undo this change using ‘apt-mark unhold’
sudo apt-mark unhold linux-generic linux-image-generic linux-headers-generic
If you are using HWE kernels, replace the package names in above commands with the ones below: