Crack all the way down the wall

[Mitchell Litam]

I recently noticed a crack about 1mm or a little less all the way from the ceiling of my room to the floor. This is on the 2nd floor. The first and third floor do not show any signs of cracks.

Is this just faulty drywall? I read it could be from the drywall settling and cracking a little or something. How can I fix this? Its in my bedroom. I dont think it is anything serious but want to confirm with more experienced people.

I have attached a photo below. Sorry Tried flipping it but it didnt work. Hopefully you get the idea.