Pointer is erratic without disabling the libinput Acceleration Profile

[Pedro Côrte-Real]

I have a Lenovo T460s and have upgraded to Ubuntu 18.04. To be able to use the trackpoint I need to disable the libinput acceleration with the following:

$ xinput --set-prop 'TPPS/2 IBM TrackPoint' 'libinput Accel Profile Enabled' 0, 1

Without doing this I get an extremely erratic pointer. Setting the acceleration profile to flat in the tweak tool doesn't fix it either.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: xserver-xorg-input-libinput 0.27.1-1
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
Uname: Linux 4.15.0-20-generic x86_64
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Sat May 19 18:26:20 2018
DistUpgraded: 2018-05-19 15:50:55,800 DEBUG icon theme changed, re-reading
DistroCodename: bionic
DistroVariant: ubuntu
InstallationDate: Installed on 2016-10-27 (568 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
Lsusb:
 Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
 Bus 001 Device 004: ID 138a:0090 Validity Sensors, Inc.
 Bus 001 Device 003: ID 5986:0706 Acer, Inc
 Bus 001 Device 002: ID 8087:0a2b Intel Corp.
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: LENOVO 20FAS5TS00
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-20-generic root=UUID=2a6b0b7e-668b-4c7f-82a9-de13f7ec5d57 ro quiet splash elevator=cfq vt.handoff=1
SourcePackage: xserver-xorg-input-libinput
UpgradeStatus: Upgraded to bionic on 2018-05-19 (0 days ago)
dmi.bios.date: 05/25/2017
dmi.bios.vendor: LENOVO
dmi.bios.version: N1CET57W (1.25 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20FAS5TS00
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40697 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrN1CET57W(1.25):bd05/25/2017:svnLENOVO:pn20FAS5TS00:pvrThinkPadT460s:rvnLENOVO:rn20FAS5TS00:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:
dmi.product.family: ThinkPad T460s
dmi.product.name: 20FAS5TS00
dmi.product.version: ThinkPad T460s
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.13.1+18.04.20180302-0ubuntu1
version.libdrm2: libdrm2 2.4.91-2
version.libgl1-mesa-dri: libgl1-mesa-dri 18.0.0~rc5-1ubuntu1
version.libgl1-mesa-glx: libgl1-mesa-glx 18.0.0~rc5-1ubuntu1
version.xserver-xorg-core: xserver-xorg-core 2:1.19.6-1ubuntu4
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.5-1ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.0.1-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2
xserver.bootTime: Sat May 19 14:54:55 2018
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.version: 2:1.19.5-0ubuntu2~16.04.1
xserver.video_driver: modeset

[Pedro Côrte-Real (pedrocr)]

After a clean reinstall of 18.04 this issue still exists. I did notice something else though. The default settings are usable but they become unusable with higher pointer speeds in settings. I end up preferring disabling the acceleration and setting the pointer speed to maximum although I'd probably like even a bit more speed.

[Pedro Côrte-Real (pedrocr)]

Testing the wayland session the pointer behavior is quite different. It requires a much smaller speed setting to be usable and seems more erratic than the X one but maybe that just needs getting used to.

[Sebastien Bacher (seb128)]

Thank you for your bug report, that's probably something that should be reported upstream on https://gitlab.freedesktop.org/libinput