PRIME Synchronization doesn't work with linux-kernel 4.15.
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
nvidia-graphics-drivers-390 (Ubuntu) |
Fix Released
|
High
|
Alberto Milone |
Bug Description
I believe this issue is pretty well known, ex. here on optimus machine
sudo cat /sys/module/
[sudo] password for doug:
Y
$ xrandr --prop | grep PRIME
PRIME Synchronization: 0 # this is the one needed to be 1
PRIME Synchronization: 1
PRIME Synchronization: 1
Though suppport seems to be there
$ dmesg |grep drm
[ 1.863499] [drm] [nvidia-drm] [GPU ID 0x00000100] Loading driver
[ 1.863501] [drm] Initialized nvidia-drm 0.0.0 20160202 for 0000:01:00.0 on minor 0
[ 1.873239] [drm] Memory usable by graphics device = 2048M
[ 1.873244] fb: switching to inteldrmfb from EFI VGA
[ 1.873323] [drm] Replacing VGA console driver
[ 1.879334] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 1.879334] [drm] Driver supports precise vblank timestamp query.
[ 1.908246] [drm] Initialized i915 1.6.0 20171023 for 0000:00:02.0 on minor 1
[ 1.945491] fbcon: inteldrmfb (fb0) is primary device
[ 1.945568] i915 0000:00:02.0: fb0: inteldrmfb frame buffer device
bug report in arch
https:/
If I install the older 384 driver then again with kernel 4.15 no prime sync but with the 4.13 kernel it works fine
I can confirm the results of xrandr and dmesg|grep drm above with the same kernel and nvidia driver versions on my system (a Thinkpad P50 with an M2000M).
An additional symptom I have is that the nvidia-settings application no longer supports PRIME at all; the PRIME Settings category in the application just doesn't appear. Here's the output when I start the application.
$ nvidia-settings
** Message: 15:46:31.025: PRIME: No offloading required. Abort
** Message: 15:46:31.026: PRIME: is it supported? no