I cant relogon to my laptop because no keyboard, mouse or touchpad input is being accepted at logon. For keyboard this includes laptop keyboard, external USB keyboard and virtual onscreen keyboard, the latter not being accessible because tab, enter key, mouse and touchpad movements/input do not work to select onscreen numbers and letters.
Specs: Ubuntu 18.04 Full USB installation that has been working for ~ 2 months HP EliteBook Laptop;
I am not a complete Unix, Ubuntu newbie at all but have come back to it recently after 2 years away so general debug or recovery mode advice would be appreciated.
I don't think it's a hardware or BIOS issue because I'm typing this question on the same laptop using Ubuntu on another USB key. So the USB stick I'm using now has the same hardware and BIOS settings as the problematic installation on the other USB stick. The other stick is a full installation that has all my settings, customizations and data for two months on the USB.
I suspect changes I made yesterday to fix a brightness issue is causing the current issue. I do not recall all the steps but I'll describe in general what I did to successfully fix the issue of the brightness not being adjustable on the full USB installation.
a. installed brightness-controller, brightness-controller-simple and xbacklight. (Not sure if package names are exact.)
b. xbacklight installation in particular had some dependencies that required installing additional packages which I don't have the names of right now (hoping to research to find the pages of instructions I followed, but even that won't be complete because I installed some things that weren't in the instructions based on messages I received on dependencies when doing the install). Edit: these are packages I installed sudo apt install xbacklight xorg xserver-xorg-video-intel. The last package had dependencies requiring additional installs.
c. I had made the following grub change and updated grub about a week ago and have rebooted many times since. It didn't fix the brightness issue then but this change is part of xbacklight install instructions I followed. Since the change had already been made to grub a week ago I did not run grub update again yesterday:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"
d. Edit: I created and added following to /etc/X11/xorg.conf as part of xbacklight install:
Section "Device" Identifier "Device0" Driver "intel" Option "Backlight" "intel_backlight" EndSection
Section "Monitor" Identifier "Monitor0" EndSection
Section "Screen" Identifier "Screen0" Monitor "Monitor0" Device "Device0" EndSection
Any help or leads are very much appreciated.
Edit: I have rolled back installs related to fixing a brightness issue, updated the system so that sudo apt-get update has nothing to install and the problem still exists.
uninstalled: xbacklight, xorg, xserver-xorg-video-intel, brightness-controller-simple, brightness-controller