Mesa hm2/hm2_7i96s.0: error finishing read

So I reported it. Please feel frre to add your own observations to the issue report.
bugs.debian.org/cgi-bin/bugreport.cgi?bug=1022170

I doubt it will become standard, ever, as it has to stop plenty of functions used for power saving, and since the era of PC domination is over, laptops and tablets rule now.
Using Preempt-RT on laptops a lot, so i know they use much more power and heat a lot more with it. On most when RT is in use running LinuxCNC the processor will remain at max speed (not turbo) all the time.

bensttech, on your 8300 do you have:

1. AMT disabled in the BIOS
2. IRQ coalescing disabled

Here is another data point:

Computer: Lenovo Thinkcentre M710q Tiny i3-7100T
BIOS:
EIST, hyperthreading, virtualization disabled
Everything under Advanced->Intel Manageability disabled
Only C1 enabled (but enabling C1E and C3 as well makes no difference)

Running 5.10 kernel:
With 1 glxgears and one YT video running I get "hm2/hm2_7i96s.0: Smart Serial port 0: DoIt not cleared from previous servo thread" and/or the error finishing read almost instantly - in fact this screenshot was a bit tricky to get since things fail so fast:




Same test but with 4.19 kernel:
Here I don't get any DoIt or error finishing read messages during the minutes I had it running.

I get the impression the problem has to do with graphics: without the YT video and glxgears running things seems a lot more stable even on the 5.10 kernel (but perhaps not stable enough, haven't tested thoroughly). I notice I get spikes on shifting focus between windows for example (this of course can be noticed with latency-histogram as well for example).

Looking into /var/log/Xorg.0.log I find this info about my graphics card (and driver?):
(II) modeset(0): glamor X acceleration enabled on Mesa Intel(R) HD Graphics 630 (KBL GT2)

Right, but 5.10 works OK on my 8300
That's why I was asking about bensttech's 8300,
as it seems possible to run 5.X kernels without these huge
latency spikes. That is, what is the difference between my
8300 and bensstechs?