I upgrade around 140 hosts (from 2.6.33 till 2.6.37), and got on many of them error/warining, flooding kernel log. Here is short snapshot:
[ 1882.057474] Uhhuh. NMI received for unknown reason 3c on CPU 0.
[ 1882.057576] Do you have a strange power saving mode enabled?
[ 1882.057672] Dazed and confused, but trying to continue
[ 2421.419732] Uhhuh. NMI received for unknown reason 3c on CPU 0.
[ 2421.419835] Do you have a strange power saving mode enabled?
[ 2421.419930] Dazed and confused, but trying to continue
[ 2636.016831] Uhhuh. NMI received for unknown reason 2c on CPU 1.
[ 2636.016934] Do you have a strange power saving mode enabled?
[ 2636.017003] Dazed and confused, but trying to continue
Full dmesg from 2 machines:
http://www.nuclearcat.com/dmesg1.txt
http://www.nuclearcat.com/dmesg2.txt
I can provide more, if required.
It seems nmi_watchdog is enabled by default, and it is causing issue. I am checking now with nmi_watchdog=0, but i need more time to confirm that.
Also i am experiencing some problem with ppp users(all of them is pppoe servers), but i am not sure it is related to that, so maybe this NMI warning is just cosmetic regression.
All systems is x86, same kernel config.
If you need more information - let me know.