https://bugzilla.kernel.org/show_bug.cgi?id=204683
--- Comment #10 from Matthias Heinz (mh@familie-heinz.name) --- Created attachment 284945 --> https://bugzilla.kernel.org/attachment.cgi?id=284945&action=edit Kernel trace
Update 2 for today.
With de00d253bc85, which is the predecessor of e6d2421343a7, I get this kernel bug.
I have never seen this one after de00d253bc85, so my guess is that e6d2421343a7 fixes it partially.
I will now start a bisect starting with the last known good kernel and de00d253bc85 and try to figure out when this one was introduced. (Back to kernel backing hell...)