Created attachment 1403639 [details]
This is a text file with commands such as lshw, lsmod, uname, etc.

Description of problem:
System hangs when going into suspend mode. The monitor goes into sleep mode but the PC never actually goes into sleep/suspend. The fan continues to run and the power light stays on. While in this hung state you cannot ctl_alt_del. You cannot ctl_alt_F(key) to toggle between tty's. You cannot re-awake the monitor under any circumstance. You cannot wake the system up by pressing the power button. I cannot SSH into the PC, even though I can when the machine is running When you press keys on the keyboard, the key backlights come on. But that's it.

The only things that do anything are to hold the power button till the machine shuts down OR press the reset button to restart the machine.

The above issue happens under normal default graphical startup mode
(systemctl get-default)
graphical.target


I have put together a list of my machine info for you in the attachment. If you would like other tests on my part I would be glad to provide them. BUT... I may possibly need some instructions, so be prepared to post me some links as to where I can read up on how to do what you're asking me for. Specifically like modprobe stuff or running specific kernel stuff.

This problem started in kernel 4.15.X
While using kernel 4.14.16 everything works perfectly.

I am curious if this may have something to do with the "Meltdown/Spectre" kernel updates. I have not updated my motherboard firmware for these exploits. But in case it is only a nouveau driver issue, I have posted all my info, including what I can find for my nouveau driver info.


Version-Release number of selected component (if applicable):
[root@localhost user]#strings /etc/os-release
NAME=Fedora
VERSION="27 (Twenty Seven)"
......

[root@localhost user]#uname -a
Linux localhost.localdomain 4.15.6-300.fc27.x86_64 #1 SMP Mon Feb 26 18:43:03 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux


How reproducible:
Completely 100% reproducible every time.


Steps to Reproduce:
1.Let the machine automatically go into suspend mode on its own.
OR you can...
2.Type systemctl suspend into the terminal.
Both cause the exact same problem listed above.


Actual results:
The machine hangs while going into suspend but never fully powers down into suspend mode. The fan stays running and the HDD continues spinning and the monitor goes into sleep(loses input signal) and the machine becomes completely unresponsive to anything but holding the power button down for 5 seconds or pressing the reset button. 

Expected results:
The machine is normally suspose to essentially turn off. the power light should start flashing and the fans and HDD should stop spinning. And when you press the ESC key the machine and monitor should come back up. 

Additional info:
If you change the login mode from graphical to text using the command...
systemctl set-default multi-user.target
  to start the machine in text mode and follow that by loging in and then issuing the command startx. Then suspend works perfect. It suspends normally and the fans and HDD will stop spinning and the power light starts flashing on and off. Just like normal.
The machine also turns back on and the monitor also turns back on normally.