I'm using a laptop with a second monitor in portrait mode above it. Like this:
__
| |
| 2|
|__|
_______
| 1 |
|_______|
I can't find settings that let me access the second screen by moving the mouse to the top of the laptop screen. Currently I need to move the mouse to the left of the laptop to access the second monitor. Is it possible to access the top monitor by moving the mouse to the top on the bottom monitor?
Edit: I'm using Ubuntu 18.04.2 LTS
Go to settings > Displays
And drag the second display to your desired position, then click on Apply.
You could use ARandR, which is an XRandR GUI. It functions as a screen layout editor, in which you can rearrange your screens in any position you'd like as well as change the orientation of a screen (that would be helpful if your monitor doesn't support that option in its own controls).
Run the following command to install it:
You can see a screenshot of it being used here: