Fixed in libinput master. Not sure when the fix will be released...

commit 1523d8bb2e066bec297f7a03ce4a0d8cada8f383
Author: Peter Hutterer <>
Date:   Mon Mar 5 13:17:43 2018 +1000

    Extract and reset the abs fuzz value for the x/y axes
    The kernel fuzz handling is buggy, especially when we want to rely on the 
    value for our hysteresis. But since this is a hw property and (at least
    sometimes) set by the driver, we can't make this a pure libinput hwdb set
    So our workaround is:
    * extract the (non-zero) fuzz into a udev property so we don't lose it
    * set the fuzz to 0 to disable the in-kernel hysteresis
    * overwrite our internal absinfo with the property fuzz
    This way we get to use the hw-specified fuzz without having the kernel muck
    around with it. We also get to use the EVDEV_ABS_ values in 60-evdev.hwdb to
    override a driver-set fuzz.
    Two drawbacks:
    - we're resetting the kernel fuzz to 0, this affects any other users of the
      device node. That's probably a minor impact only.
    - we can only save this in a udev property there's a risk of this 
      getting lost when playing around with udev rules. That too should be a 
    Signed-off-by: Peter Hutterer <>

commit 1b64888a2248af2a287365598cf520e4e2be33fd
Author: Peter Hutterer <>
Date:   Fri Feb 23 11:44:23 2018 +1000

    touchpad: enable hysteresis based on a 0 fuzz value
    If the fuzz is 0, assume we don't need hysteresis and use the wobble 
    code instead. If the fuzz is non-zero, enable it by default.
    Signed-off-by: Peter Hutterer <>

** Bug watch added: Bugzilla #105303

** Changed in: libinput (Ubuntu)
       Status: Triaged => In Progress

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  Lenovo Yoga 11S touchpad is jittery

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