I have always had issues with the touchpad scrolling on my T440, but have been able to remedy them using the instructions shown here:
https://blog.milan-ihl.de/posts/16618-enhance-your-archlinux-experience-on-the-t440/
I switched to Solus Gnome yesterday and attempted to do the same fix, but got the following message when attempting to update the grub config file:
Generating grub configuration file ...
WARNING: Failed to connect to lvmetad. Falling back to device scanning.
done
It says done, so I thought it may have worked just fine in spite of the error, but I am still having the same issues. I never had any issues previously after following these instructions so I don't know what update it makes to the grub config file, but looking in there now, I don't see anything related to psmouse.
Does anyone have any ideas about what I'm doing wrong, or if there is another way to fix this? Thanks for your help.