I upgraded to Ubuntu 18.04 without issues. However, after a certain update suddenly the laptop touchpad stopped working. I tried few fixes suggested and ended up disabling even the keyboard.
I didn’t have time to debug and left it as it is for few days. Today, finally I looked into it and found a simple fix.
You need to install Ubuntu Hardware Enablement. The Ubuntu LTS enablement aka HWE or Hardware Enablement stacks provide newer kernel and X support for existing Ubuntu LTS releases. The process is simple:
sudo apt install --install-recommends linux-generic-hwe-18.04 xserver-xorg-hwe-18.04
Reboot and everything should be working fine.