(In reply to Stefan Dirsch from comment #1) > Thanks. This sounds like a kernel regression. Since kernel 5.9 or already > 5.8. I suggest to set > > drm.debug=0xe > > as kernel boot parameter and then run 'dmesg' command after this issue > happened, so we may see the culprit. I've got this parameter set and will report back once with dmesg output once the problem recurs. (In the meantime, maybe Michael wants to do the same.)