How to detect a Kernel Panic!

Pes88 · Apprentice Joined: 06 May 2009 Posts: 229

Hi,

I have a big issue with my kernel! When I'm using my pc it freezes, I think, the kernel causes this because after that, the only way to use the pc is reboot with the power button. I explain myself better...

I've recently bought a new laptop with the Intel i7 3610, Nvidia 630 Optimus technology, It should be very nice computer but not long after buying it I had troubles.

Firstly, I've installed Ubuntu ( in order to install GENTOO ), and that problem occured.. When I am using the pc gets stuck, completely random.
I thought it was a problem which had to do with the Ubuntu Kernel. So, I decided to install Gentoo with a my kernel ( without any particular configuration, just the default config ), the pc still freezes...

I haven't found anything weird in the kernel messages (dmesg). I don't know how to find useful information linked to crushes.... :cry:

what shall I do to find out what cause this?
What shall I post to help you to understand better my problem?
Also I would like to be sure that isn't a Hardware problem..

I have also a Windows installation which works properly!!!

I have an idea about this, could the nouveau driver cause this? Because I have that driver in both systems... Also, I'm using lvm, but difficultly it can cause this because it is quite stable and tested software... isn't it?
_________________
Pygoscelis papua, chiamato Gentoo dagli abitanti delle isole Falkland/Malvinas, noto per essere il pinguino più veloce!!! XD

aCOSwt · Posted: Thu Jun 14, 2012 12:53 pm Post subject:

Do you mean it freezes only under X ?
And that CTRL+ALT+F1 does not bring you back to console ?
And that CTRL+ALT+BACKSPACE is intefficient ?

Well, if yes then do try with the nvidia proprietary drivers (emerge nvidia-drivers) and in the meantime, post your /etc/X11/xorg.conf and pastebin your /var/log/Xorg.0.log
_________________
In theory there are no differences between theory and practice. In practice, there are.
Don't try to understand my posts. Immanuel Kant never did, he thinks that only music and laughter do not have to mean anything.

DaggyStyle · Advocate Joined: 22 Mar 2006 Posts: 4735

you don't need to install ubuntu in order to install gentoo.

does your pc freezes or after x start screen is black?
_________________
Only two things are infinite, the universe and human stupidity and I'm not sure about the former - Albert Einstein
ProjectFootball

Pes88 · Apprentice Joined: 06 May 2009 Posts: 229

DaggyStyle · Advocate Joined: 22 Mar 2006 Posts: 4735

Pes88 · Apprentice Joined: 06 May 2009 Posts: 229

I made a mistake, the screen is not black, it's just stuck and I CANNOT use the pc! Sorry...
However I think it's a kernel Panic.

aCOSwt · Posted: Sat Jun 16, 2012 9:42 am Post subject:

DaggyStyle · Advocate Joined: 22 Mar 2006 Posts: 4735

Pes88 · Apprentice Joined: 06 May 2009 Posts: 229

John R. Graham · Posted: Sat Jun 16, 2012 10:25 am Post subject:

The /var/log/messages file will preserve messages from the previous freeze, so it's still potentially useful to post. :wink:

- John
_________________
This space intentionally left blank.

DaggyStyle · Advocate Joined: 22 Mar 2006 Posts: 4735

Pes88 · Apprentice Joined: 06 May 2009 Posts: 229

DaggyStyle · Advocate Joined: 22 Mar 2006 Posts: 4735

cach0rr0 · Posted: Sun Jun 17, 2012 8:13 am Post subject:

a)you need to emerge a syslog daemon, such as syslog-ng as DaggyStyle suggested
b)if it's really not showing for whatever reason, if your system has a serial port, you can terminal in via serial console and watch the panic - if in fact there is one

I normally confirm a panic by trying to contact the box from another host on the same LAN - it doesnt always work, since sometimes a network driver may be what's crashing, but it can be helpful - all the better if you can try to ssh from another local host to your supposedly frozen PC.
_________________
Lost configuring your system?
dump lspci -n here | see Pappy's guide | Link Stash

Pes88 · Apprentice Joined: 06 May 2009 Posts: 229

I've installed syslog-ng!

These logs are when the system had a freeze!

dmesg :
http://pastebin.com/grCYVjHH

Xorg :
http://pastebin.com/i0W4JqPK

Messages :
http://pastebin.com/nypM0kfT

thak for helping..

_________________
Pygoscelis papua, chiamato Gentoo dagli abitanti delle isole Falkland/Malvinas, noto per essere il pinguino più veloce!!! XD

DaggyStyle · Advocate Joined: 22 Mar 2006 Posts: 4735

when the freeze occurs, does the leds on the keyboard blink?
_________________
Only two things are infinite, the universe and human stupidity and I'm not sure about the former - Albert Einstein
ProjectFootball

Pes88 · Apprentice Joined: 06 May 2009 Posts: 229

DaggyStyle · Advocate Joined: 22 Mar 2006 Posts: 4735

well your system doesn't panic, it just freezes.

try latest kernel.
_________________
Only two things are infinite, the universe and human stupidity and I'm not sure about the former - Albert Einstein
ProjectFootball

DirtyHairy · Posted: Mon Jun 18, 2012 10:50 am Post subject:

Well, I have to second Pes88, it could be a panic. The fact that the logs are empty is natural, a panic stops userspace and therefore usually is not logged. Blinking keyboard lights are an indicator, but as all other indicators (no ping, lights do not change on caps/numlock etc.), it's absence doesn't indicate that _no_ panic occured. Another test would be to activate magic sysrq in the kernel config and try the various key combinations in /usr/src/linux/Documentation/sysrq.txt . If you have access to another machine in the network, try ping and ssh.

However, irrespectively of whether panic or not, a good first stab it fixing it is to let the system run for prolonged time (e.g. updating) without any video drivers or X, just a plain VGA terminal; if it doesn't freeze, you know it is video. As you have an intel IGP in addition to your nvidia optimus, try deactivting nouveau in the kernel config (your dmesg shows that you are loading it), it might well be the culprit.

Pes88 · Apprentice Joined: 06 May 2009 Posts: 229

DirtyHairy · Posted: Tue Jun 19, 2012 11:57 am Post subject:

I disagree with your opinion of disabling graphics being useless. As you can't get any log data from the incidents, your only way of nailing down the problem and solving it is to systematically simplify your configuration piecemeal and try to provoke the crash after each change long enough that you can be confident that it is gone. Other than that, you can just hope for a kernel change mysteriously solving the issue, which might or might not happen. In the worst case, the issue might be a hardware problem, but I doubt this.

For starters, take your discrete nvidia chip completely out of the equation by removing all drivers for it; your IGP will still work, but when it crashes, you will have excluded the nvidia. Then go to the plain terminal, as I told you, then remove more hardware drivers (wifi, network, you get the idea) until you get a configuration which seems to run stable. After that, you can start to look for a fix. I know that this is slow and painful, but it is the only reliable thing to do in absence of a log.

The only other pointer I can give you is to try aquiring a log of the hang, either using ssh (if the machine still responds), a serial console or netconsole. You can also run memcheck to check for memory and / or CPU issues. BIOS update is another desparate thing to try. As for the magic sysrq: if it doesn't work, you can be confident that something serious has happened and the kernel has panicked or hung. I don't think you can reliably deduce anything on the system state if it works though.