I don't know about ubuntu 18.04 but if it has a new enough software stack, specifically xorgproto/X.org, it may already be hiding the HMD with non-desktop. However, direct mode does not work yet without patching mesa/radv and xf86-video-amdgu or using modesetting ddx.
I have some more info about the current status at https://haagch.frickel.club/#!drmlease.md
tl;dr: If you run xrandr and see the HMD as disconnected but having modes, it is being hidden from X due to the non-desktop property. In this case you can termporarily enable extended mode with xrandr --output HDMI-A-0 --set non-desktop 0, subsituting the output name where your Vive is of course.
I found out it was the DisplayPort cable I was using. Switched to a DVI-D to HDMI cable for my monitor, and the Vive's included HDMI cable to connect to the link box. Now the Vive displays things. Will test more tonight. Thanks for the info!
Nothing extracted yet.
Your system information
Please describe your issue in as much detail as possible:
After having installed Kubuntu today, and installing the Vulkan Mesa drivers and following the other instructions here, I managed to get the Vive completely working except the most important part: the display. Motion works, controller works, setup works, what I'm seeing in the compositor window (that I can't move to the Vive display) works great.
It seems to me that my AMD card not supporting direct mode, and the latest -buntus using Linux 4.15, could be the problem:https://www.phoronix.com/scan.php?page=news_item&px=Linux-4.15-Non-Desktop-Quirk
EDIT: This person got their Vive working with Linux 4.15 on Debian Testing a month ago. Not sure what they have that I need, I tried moving that ICD file too.
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