After the latest stable update something is broken with the touchpad (Laptop HP Elitebook 745 G6). From time to time it stops for about half a second and sometimes inserts a click. Every such stop triggers a message in dmesg:
i2c_amd_mp2 0000:04:00.7: received irq without message
It is quite annoying, since the more load on the system there is, the more often it happens, making the work problematic. It has never happened before the last update and it happens on both new kernels 5.10 and 5.9. Seems to be a problem with touchpad losing interrupt number or something like that. Any idea what changed?
When I’ve restored kernel 5.9.11-3, the issue stops and the touchpad works correctly. So I suppose, that something has been changed in how the kernel handles interrupts from the touchpad in kernel 5.10 and it has also been backported to 5.9. Any idea?
Unfortunately, I haven’t tested it enough - it still happens with kernel 5.9.11-3 as well. So the problem is not in kernel I suppose, but somewhere else. When I move the touchpad I see in top that processes Xorg, gnome-shell, gjs, libinput-debug and irq/72-SYNA308D have increased CPU usage (increased meaning like 5-6% each of them), which I think should not be the case with plain moving of cursor with a touchpad.
OK, I’ve found out that the message was being generated into dmesg even before the last stable upgrade. Earlier I just checked the dmesg logs that apparently didn’t have any such messages (short time to restart etc.) Anyway, I can find the message even before the last stable upgrade. However, what has changed, that makes the difference is how gnome shell handles those short outages. In the new Gnome shell (3.38.2), whenever the cursor stops, most of the times it also does a click, which is very annoying, since after moving it does a drag & drop most of the times. When I have downgraded gnome shell and mutter to the previous version (3.38.1), the cursor stops to a much shorter time (I don’t even notice it), but more importantly it doesn’t trigger a click, so it’s harmless. This is the main reason why it because annoying after the stable upgrade to Gnome 3.38.2. Happens in both Xorg and Wayland.