Public bug reported: [Impact]
* This impacts all Ubuntu releases which received an update of x.org to 1.18.3 or newer, i.e. Ubuntu 16.04, 16.10, 17.04 & 17.10 * End users are unable to use their USB displays unless they workaround the problem which currently involves disabling pageflip for modesetting in x.org.conf file * The fix which has been submitted to x.org extends blacklisting mechanism so the EVDI kernel module which is essential for DisplayLink USB 3.0 devices to work is correctly recognised by x.org. Then the PRIME sync is disabled in such case; The patch can be found here: https://cgit.freedesktop.org/xorg/xserver/commit/?id=fbd80b2c8ebe9fd41229dc5438524d107c071ff1 [Test Case] 1. On a PC device with Ubuntu install DisplayLink SW for Ubuntu v1.3.54 downloaded from http://www.displaylink.com/downloads/ubuntu. Detailed requirements and instructions can be found here: 2. Plug in a DisplayLink USB 3.0 compatible device, e.g. Dell D3100 docking station 3. Plug in an external monitor (HDMI or DisplayPort) to the docking station Expected result: The external monitor should light up and show the desktop Actual result: The monitor remains black or shows frozen desktop. [Regression Potential] * The patchset extends number of modules for which x.org changes its functionality. It checks if "evdi" string is in the syspath so it is quite unlikely there would be any impact on anything else then USB 3.0 displays which use EVDI module. [Other Info] * The patch has been applied to Ubuntu x.org source code built and tested. ** Affects: xorg (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1720133 Title: USB 3.0 displays are black on Ubuntu after x.org update to 1.18.3 or newer To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1720133/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp
