(In reply to Michel Dänzer from comment #10)
> [T]hat looks like an RCU or other core kernel issue, not directly
> related to the graphics drivers.

Hi Michel:
If so, should I report that probable non-graphics kernel bug (with my
crash-report tarball) elsewhere?  Or do you suggest I just forget it until I
see what are the remote graphics results of idle=nomwait over the course of the
next couple of weeks AND (if that is a success) the direct graphics results of
idle=nomwait for a couple of more weeks after that?