Arch Linux

getagrip

Member

Registered: 2007-12-26

Posts: 45

system freeze

I've had problems since updating to kernel 2.6.33.
My system freezes now and then, I can still move the mouse very slowly but my keyboard is gone so I have to push the power button to shutdown.

The kernel log states the following:

"Uhhuh. NMI received for unknown reason a0 on CPU 0.
You have some hardware problem, likely on the PCI bus.
Dazed and confused, but trying to continue"

I also get black rectangles on screen which disappear only when resizing the window.

Going back to 2.6.32 I do not have these issues.
Also I have disabled "Desktop Effects" and KMS.

2.6.33-ARCH x86_64

xf86-video-ati 6.12.192-1 

xorg-server 1.7.6-3

kdemod-kdelibs 4.4.2-1

Anyone have similar issues?

Vain

Member

Registered: 2008-10-19

Posts: 179

Website

Re: system freeze

Yes, I do. I'm on i686 and using Xfce, though. It only happens on my laptop which got a Mobility Radeon X1300 -- no desktop effects, no KMS. I have noticed this before 2.6.33, that's for sure. However, it happens way more often nowadays.

I don't have any idea yet what's causing this. At the moment, I'm testing the standard vesa and fbdev drivers...

Btw, you could set up an acpi-handler in /etc/acpi/handler.sh like this:

...

case "$1" in
    ...
    button/power)
        case "$2" in
            PBTN)
                logger "PowerButton pressed: $2 --> init 0"
                init 0
                ;;
            *)
                logger "ACPI action undefined: $2"
                ;;
        esac
        ;;
    ...
esac

That allows you to cleanly shutdown when it's "frozen": Just hit the power button shortly. But it may take a while, so be patient.

---

Why "Open Source" misses the point of Free Software

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 19,801

Re: system freeze

Just for clarity, NMI means "Non-Maskable Interrupt".  This is a hardware function that is reserved for extremely high priority asynchronous exceptions. They cannot be shut off in the processor and it must respond to them.

Something in hardware is triggering them and the kernel has no idea why it happened.  NMIs are usually reserved for things like (in the olden days) memory refresh cycle initiation, or, in more modern times, things like notification that a power failure is immanent, so stop writing things to disk and sync them while you have time.

This is a strong function of the hardware architecture -- you will probably need to do research on your specific hardware.  You might look around in your BIOS settings, if there are any references to enabling NMI, disable them.

---

Nothing is too wonderful to be true, if it be consistent with the laws of nature -- Michael Faraday
Sometimes it is the people no one can imagine anything of who do the things no one can imagine. -- Alan Turing
---
How to Ask Questions the Smart Way

Vain

Member

Registered: 2008-10-19

Posts: 179

Website

Re: system freeze

Hi,

@ewaller: Thanks for the explanation.

@getagrip: I must apologize, according to this page, our issues may not be related at all. Looks like these are generic symptoms ("random" freezes, mouse moves very slowly, ...) that can be caused by nearly anything. Didn't know that.

Well, maybe I solved my issue -- with some good luck, it could help you, too. I figured that Xorg freezes every time I do a right click on an icon on my desktop (I do that like once a month, so I haven't noticed...). So I finally got a test case. Now, some time ago I needed to add this to my xorg.conf to prevent some screen artifacts:

Section "Device"
    ...
    Option "EXAVsync" "on"
    ...
EndSection

By removing this line, the freezes (when right-clicking an icon) are gone -- and no artifacts. I need to do some more testing, but for now it looks good.

---

Why "Open Source" misses the point of Free Software

getagrip

Member

Registered: 2007-12-26

Posts: 45

Re: system freeze

Going back to 2.6.32 I do not have these issues.

I must revise this statement. Even with 2.6.32 I have this issue, just not as often.

I have checked both chipset and RAM with memtest-x86 in version 3.4 and 3.5 which gave no errors.

Before I backup my harddrive and copy my old WinXP image onto it to see if it is really a system issue
I would like to ask if anyone knows of another mem-checker of the same quality as memtest-x86 so I
can be REALLY sure that I do not have screwed up hardware.
Thanks!

getagrip

Member

Registered: 2007-12-26

Posts: 45

Re: system freeze

All right,

after having used Windoze again for a while and no freezes showing up it must be a system-related problem, hopefully with one of the next kernel / ati-driver releases it will disappear.