Issues with Ubuntu 16.04.2 with kernel 4.8
 

I've just upgraded my Dell laptop to Ubuntu 16.04.2 with kernel 4.8. External monitor is totally unusable, everything slows down to the point that it freezes after a while. I attach 3 outputs of the Linux support tool. 01.zip contains the output with external monitor disabled, only built-in (everything is fine). 02.zip the output in the dual monitor configuration (freeze). 03.zip with the builtin monitor off, only external (freeze).

I tried to uninstall the driver then reinstall it again. Now it seems that the external display is completely ignored by the Operating System. No trace of DisplayLink among running processes. Attaching the output of the Linux Support Tool.

I've even tried to run a live Ubuntu 16.04 with kernel 4.8 (the one one would eventually get if he/she downloads ubuntu since today), tried to install the driver and the same happens. No sign of life from the external display.

I smell some problems with USB on your machine or maybe the connection of the dock to the laptop.

If you inspect the dmesg of the most recent attachment, it's full of:
[ 108.450644] usb 4-1-port4: Cannot enable. Maybe the USB cable is bad?

Cheers,
Michal

I don't think so... the cable is the same I used with the old kernel. Moreover, the docking station has working usb ports, audio outputs and LAN...

I'm more and more convinced that this is a software issue. I've tried to connect my docking station to another pc not upgraded to kernel 4.8. No errors in the syslog related to the cable. Then I've plugged it again to my laptop and the monitor woke up. No errors in the syslog related to the cable. But still unusable (very slow, high cpu usage by DisplayLink server). I attach the report of the Support Tool.

I am trying to get my head around it :)
Could you please clarify one thing: do I read correctly that this happens when you close the laptop lid (so the built-in screen is off)?
If yes, is the same problem visible when you keep the lid open (and do not disable the built-in screen)?

Cheers,
Michal

This is what it looked in the first place. I tried again this morning (the kernel updated, I hoped this was fixed) and it seems that the problem arises just connecting the external monitor, no matter if the lid is on or off. The problem is significantly amplified when I open Google Chorme, which is unusable. If I unplug the external monitor or I connect it with the displayport, everything works fine.

Let mi know it there's any test I can run to help you understand. Thank you!
I hoped that this morning's update of kernel and hardware enablement stack could fix the issue but still no luck. I attach the report of the support tool.

Same problem on Thinpad T540p
 

Hello,

I'm also running Ubuntu 16.04.2 with the 4.8 kernel and I'm experiencing massive slowdown as well. I tried to upgrade the driver to the version 1.3.52, but it made no observable difference. Chrome is really unusable, even gedit is super slow.

I believe I was on 4.8 kernel even before and it worked fine. The slowdown happened when I enabled the full Ubuntu HWE stack and Xorg got upgraded to a newer version.

glxgears reports 1 FPS when I move the window to a display connected via DisplayLink. Unfortunatekly I don't know FPS before the HWE upgrade.

I confirm each and every symptom. And the same happens if I boot Ubuntu with the 4.4 kernel choosing it from GRUB.

modesetting driver to blame?
 

Interestingly enough the slowdown appears to be caused by the modesetting driver the new Xorg uses for Intel cards by default!
I explicitly configured the old driver in my xorg.conf and it seems to work fine again!

Section "Device"

Identifier "Card0"
Driver "intel"
BusID "PCI:0:2:0"

EndSection

Apparently there is some bad interaction between the modesetting and DisplayLink drivers. This should be addressed as the modesetting thing is now default in many distributions.

I'vre tried your workaround but id did not work. But I may have done something wrong. Here's what I did. I edited the file /usr/share/doc/xserver-xorg-video-intel-hwe-16.04/xorg.conf which looked like this:
and I replaced it with your code. But maybe Card0 and the bus address are not correct on my machine, or I've edited the wrong file. Can you help me with that?
Thank you

xorg.conf
 

I actually used `# Xorg :1 -configure` to generate a config file. Strangely enough it did generate a config file with the intel driver not the the modesetting driver. Then I just copied this file into /etc/X11/xorg.conf

It's using the old(?) config style where all options are in a single file, so perhaps it's not very future-proof and it might break with another update. For a reference, here is the generated file.

I am getting around the slow graphics when I am turning on the Laptop display additionally. But I always have to reconnect the dock after X started. Things were working with 4.4 and older driver.

Same:
Thinkpad T430u (intel graphics - modesetting)
Thinkpad Dock USB3.0 Basic (latest drivers)
Ubuntu 16.04.02 - 4.4.0-65-generic #86-Ubuntu

Mouse movement is smooth, but keyboard input lags (on external displaylink screen).

Strangest behaviour I see, when I let the e.g. chrome window overlap just some pixels into the laptop screen, the lag (while typing into the addressbar) is not there, or at least less. If I pull the window completely on the external (displaylink) screen, it lags like 1hz.

For me with ubuntu 16.04.2 it doesn't work too. It worked with 16.04.1

Can somebody @DisplayLink like mlukaszek tell us if anybody is taking care of this issue? Because it seems impossible, or at least I don't know how, to rollback to the stable situation. Thanks a lot.

It seems that the workaround described here http://displaylink.org/forum/showpos...98&postcount=1 attenuates the issue. Currently I've connected the external monitor and it seems to work, even if it is not super smooth. Even if the "hot swap" connection of the monitor makes the session crash and disconnect, coming back to the greeter page.

Got it working
 

jerrinot's method worked for me! For anyone confused, my xorg.conf file in /usr/share/doc/xserver-xorg-video-intel-hwe-16.04/xorg.conf looks exactly the same as giuliocoluccia's. I did not edit that. I navigated to /etc/X11/ and ran the command "sudo gedit xorg.conf" to create a new file and then copied and pasted jerrinot's file (this file ) and saved it. Restarted my computer and now there is no more lag on either of my two monitors. I had to go to System Settings > Displays and fix some issues cause for some reason it had my built-in display inside the HDMI monitor and the Display Port monitor was turned off.

HOWEVER, sometimes Chrome does some strange flashing. It's not often but it is happening. But no lag, scrolling is super smooth, no problems other than the occasional flashes.

My setup: Ubuntu 16.04.2 on a Dell XPS 9350 using a StarTech USB3DOCKHDPC. I have one monitor connected to my USB-C port via HDMI, and one monitor connected to the docking station via Display Port. I could try the HDMI cable in the docking station, too...but I'm kind of scared to after spending so much time trying to get my dual-monitor setup working. XD

UPDATE: Finally plugged in both Display Port and HDMI to docking station. Both monitors working fine. Ocassional flashing still there though. My PC is getting hot now and the fan is pretty loud.

So, I started with the problems all the other people her have with Ubuntu 16.04 on the current XPS 13 version with a D3100 dock.
After multiple steps of debugging and upgrading with all variants of states from having no monitors, not being able to type (that was a bummer) I'm now at the state fotografo described with the xorg.conf on 17.04 and everything seems to work, more or less smoothly.

This should be fixed in any way, I've spent up to two full working days just running around my notebook trying to get a ready to work environment back again...

How do you guys get your audio work? Mine doesn't, neither the suspension operation closing the computer lid.

I have the same problem after re-installing last Ubuntu 16.04 and displaylink last driver (4.1). Computer freezes randomly and I have to reboot my laptop. Before re-installing the Ubuntu I had some previous version of displaylink driver and I didn't have this problem.