On Fri, 2021-07-30 at 22:49 +0200, Thomas Gleixner wrote:

quoted

First symptom is KDE/Plasma's task manager going comatose.  Notice soon

KDE/Plasma points at the new fangled rtmutex based ww_mutex from
Peter.

Yeah, that seems to be most of the delta from 50->62 [now 63] commit
delta, and the 50 turning out to be what I was already running.  I'm
staring, but as yet, nothing has poked me in the eye.

 I tried to test the heck out of it...

And futextests, rt-tests etc work fine, just stay away from GUI.

Which graphics driver is in use on that machine?

The all too often problem child nouveau, but I don't _think_ it's
playing a roll in this, as nomodeset hangs as well.  I'll stuff it into
lappy (i915) to double check that.

	-Mike