Strange things going on with 4.8

[Daniela]

Hi all!

I'm having problems no end on my 4.8-STABLE box, and I hope you can help me.

My processes get lots of signals (mostly 6, 10 and 11), and my kernel dumps 
core very often. I have the core dumps from the 4 latest crashes. See 
attachment for more info.
Notice the common values for IdlePTD and initial pcb. Does this mean anything?

There are other problems as well:

1) Some time ago KDE was hanging in disk wait state forever.

2) When rebuilding the world, make sometimes fails, but when I retry, it 
either works, or fails elsewhere. I have not seen this on -STABLE, only on 
5.0-RELEASE (on the same computer).

3) Programs are frequently closing when they shouldn't, but without any signs 
that they recieved a signal. I haven't managed to catch one with gdb yet.

4) X11 (or KDE) locks up very often, only a hard reset brings the OS back.

5) The absolutely strangest thing I've ever seen happened today:
The console screensaver was running, and when I pressed a key, everything 
locked up (I could not even ping the box).
The view was locked to ttyv0, the cursor disappeared. When I tried to switch 
to another terminal (with ALT + Function key), it either beeped or did 
nothing. It was completely random, sometimes it beeped, sometimes not.


I have already tested the memory (no errors). There weren't any problems with 
4.6-RELEASE on my old box.

FreeBSD is awesome, but why is it not working for me?
Please help me.

Daniela