Kernel panic - not syncing: Attempted to kill the idle task

Thanks for including the Xorg log file. I notice there is a backtrace in the log:

Backtrace:
0: /usr/bin/X(xf86SigHandler+0x81) [0x80c9581]
1: [0xffffe420]
2: /usr/bin/X(SecurityLookupIDByType+0xab) [0x807847b]
3: /usr/bin/X [0x8168bfb]
4: /usr/bin/X [0x8164325]
5: /usr/bin/X [0x815755e]
6: /usr/bin/X(Dispatch+0x1aa) [0x808f47a]
7: /usr/bin/X(main+0x495) [0x8076f05]
8: /lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xe0) [0xb7db3050]
9: /usr/bin/X(FontFileCompleteXLFD+0x1e1) [0x8076241]

Do you always see this exact error trace when it crashes?

Please test gutsy-rc when it is released, and let us know if the issue remains.

I just tried the Gutsy RC, and I'm afraid the problem remains. Note that I don't always get the error trace: often the machine just freezes, forcing a hard reboot. Is there anything else I should try? Note that even in Edgy, the nv driver is not particularly stable: it crashes every couple of days (which is still better than Gutsy's every couple of minutes, though...).

I have now tried the final Gutsy, and alas, the problem is still there. So far I've only managed to get system freezes, no crashes (did you guys change anything?). However, the freezes happen far too frequently for Gutsy to be viable (the system doesn't seem to last more than a few minutes).

Hello Dario. Could you please look, if the fan of your graphics card runs? Maybe the bug is not software related? Do other users of this card experience the same behavior with gutsy? We will see.

Sorry, but I fail to see how the problem could *not* be software related. After all, this same card worked "perfectly" with the Breezy, Dapper, and Edgy (which I'm currently running) releases.

(Note: I say "perfectly" because even in Edgy, X still crashes every few days or so. The problem with Gutsy is that it freezes every couple of minutes!)

I decided to risk it and install Gutsy anyway. And I'm sorry to report that the problem with the nv driver remains: X is very unstable, completely freezing the system every few minutes.

I am running out of options here, because I don't feel like reinstalling Edgy all over again...

I am attaching the Xorg.0.log.old file. It is very informative: towards the end you can see the backtrace of the error that caused X to crash.

And here's another Xorg.0.log.old file containing a backtrace.

I noticed that when it starts, X tries to load quite a few modules from the /usr/lib/xorg/modules directory. Is there anyway to control which modules are loaded? (so I can isolate the error)

Yes, in xorg.conf in the modules section add

  Disable "<modulename>"

I've also written up a draft of a "Ubuntu X Debugger's Handbook" with some additional tips and tricks (and please help flesh out bits you know about). https://wiki.ubuntu.com/X/Debugging

What if the bug is in the kernel and not in the nv driver? I say this because if I'm on one of the virtual consoles (say, F2) while the freezes occur, I see a kernel backtrace and the kernel panic message "Not syncing - fatal interrupt error".

Note that the last kernels that worked fine were Dapper's. Edgy's kernels were hit-and-miss: some were good, some where bad.
Linux-image-2.6.17-11 was the last *good* one. I couldn't use Edgy's 2.6.17-12 because it kept freezing my machine.

If you happen to have a digital camera, please take a photo of the kernel backtrace output and attach that.

I am attaching a screenshot, and more will follow eventually. Can you perhaps correct the bug's package, or should I submit a new one affecting linux-image?

Another note: I took the time to install Debian Sarge and Lenny, and they are also both affected.

I am attaching a new screenshot, this one with a different sort of panic.

Also, on my previous message, I meant to say that "Debian Etch and Lenny" are also affected, not "Debian Sarge and Lenny"...

And here's the third screenshot; this one is also of the "fatal exception in interrupt" kind, but it seems to occur in a different spot from the previous one.

As you might have already deduced from the lspci output, the only "odd" thing about my system is that I am using a PCI card to provide USB 2.0 and Firewire ports, since the motherboard is reasonably old and only supports USB 1.1. (And yes, I will try removing this card and see if the error remains).

I removed the PCI card, but the problem still occurs: the kernel panics all the time. I am attaching a new screenshot, this one of the "Attempted to kill the idle task" variety.

One thing did occur to me: my CPU is an AMD Athlon XP (k7 arch). Could there be an incompatibility with linux-image-generic?

Due to the kernel panics attached, I'm changing this to list as a bug in the kernel.

The suggestion was put to me that this might be due to broken / buggy hardware, and that testing (say) a Feisty (or other) Live CD would help to verify that possibility.

A personal suggestion would be to run the "memtest" option from the boot menu, and let memtest86 do a thorough scan and see that the system RAM is working correctly.

If you see any crashes there, check the BIOS menus for hardware temperature monitoring and make sure the system isn't overheating.

If you see any memory errors reported, then you need to replace the RAM chip(s) effected.

Thanks for your attention; actually, running the memcheck was one of the first things I tried: it ran overnight without any problems. I also checked the CD MD5SUM, burned at only 4x, and checked the CD for defects from the menu option -- and all was fine.

Very important note: this system ran Edgy fine. Between Edgy and Gusty something must have changed that it's causing these problems.

I am now recompiling the Ubuntu kernel source, setting the target for K7, and turning off some of the newer features like the "tickless kernel".

I'll keep you posted.

I compiled a new kernel "the Debian way". The only thing I ended up changing was the architecture: I set it to K7.

The compilation process itself was painful, because gcc kept segfaulting and every now and then the kernel would panic. On top of that, the new kernel wouldn't even boot: it produced one of those "not syncing" panics in the first steps of the boot process.

I can never over-emphasise this point enough: Edgy worked fine! Something must have changed between Edgy and Feisty/Gutsy that is making my system so unstable. Did you guys change any of the default gcc options, for instance?

Can you use an Edgy (or other suspected working) live-CD and verify that it still works fine. If so, we might have a base to start from in comparing configs.

Okay, I left the Edgy live-CD running for some 20 hours straight: I played with most applications, and I left it overnight running IO intensive tasks on the console. And guess what: it never panicked. Also, two nights ago I left system running memcheck overnight, and there were no errors reported.
I think it is safe to conclude that the problem isn't hardware.

Important things to take into account:

1) Debian Etch and Lenny are also affected;
2) I know Edgy runs fine; however, since I never upgraded to Feisty, there's a chance the problem began there, I just don't know.

Now, I have access to another machine running Gutsy, and I can use to to cross-compile (different arch) new kernels to try out. If it would help you to send me patches and/or kernel configs, please do so!

Could the problem be GCC related? I noticed that Feisty/Gutsy used a different version than Edgy.

I am assigning this bug to the 'ubuntu-kernel-team' per their bug policy. For future reference you can learn more about their bug policy at https://wiki.ubuntu.com/KernelTeamBugPolicies .

I would like use kubuntu 7.10 desktop with en old toshiba laptop. I got this kernel panic and the laptop froze. The laptop has 32M ram, and this take this error.

The Hardy Heron Alpha series is currently under development and contains an updated version of the kernel. It would be helpful if you could test the latest Hardy Alpha release: http://www.ubuntu.com/testing . You should be able to then test the new kernel via the LiveCD. If you can, please verify if this bug still exists or not and report back your results. Thanks.

Well, I just tried the Hardy Alpha 5 release, and the same problem still occurs. The system will typically last only a few minutes before kernel-panicking and freezing.

Hi Dario,

Sorry for the delayed response. When running the latest Hardy kernel, can you attach either a digital photo of the panic or the dmesg output which captures it? Thanks.

I am attaching a digital photo of the panic. These are so frequent that I have yet to finish a successful installation.

Has this issue been resolved?

I've just downloaded Ubuntu and tried to install it on my old Toshiba (which did run Windows ME) and I'm having the same error.

The Ubuntu Kernel Team is planning to move to the 2.6.27 kernel for the upcoming Intrepid Ibex 8.10 release. As a result, the kernel team would appreciate it if you could please test this newer 2.6.27 Ubuntu kernel. There are one of two ways you should be able to test:

1) If you are comfortable installing packages on your own, the linux-image-2.6.27-* package is currently available for you to install and test.

--or--

2) The upcoming Alpha5 for Intrepid Ibex 8.10 will contain this newer 2.6.27 Ubuntu kernel. Alpha5 is set to be released Thursday Sept 4. Please watch http://www.ubuntu.com/testing for Alpha5 to be announced. You should then be able to test via a LiveCD.

Please let us know immediately if this newer 2.6.27 kernel resolves the bug reported here or if the issue remains. More importantly, please open a new bug report for each new bug/regression introduced by the 2.6.27 kernel and tag the bug report with 'linux-2.6.27'. Also, please specifically note if the issue does or does not appear in the 2.6.26 kernel. Thanks again, we really appreicate your help and feedback.

Hi,

I have just tried the Beta 1 of Intrepid Ibex, and the problem still happens. I am even unable to complete an installation, because the kernel panics and the computer just freezes. So it seems that kernel 2.6.27 is also affected by this problem.

As I mentioned before, Edgy runs fine, so the problem was introduced with recent kernels. Something ACPI related, perhaps?

Hi again,

One extra bit of information: with the Intrepid Ibex Beta 1, either after selecting the "Try out this CD without installing" or the "Install Kubuntu" option, and just before the Kubuntu splash screen appears, there is message shown on the top of the screen. The message reads "ACPI: unable to load the system description tables".

Per a decision made by the Ubuntu Kernel Team, bugs will longer be assigned to the ubuntu-kernel-team in Launchpad as part of the bug triage process. The ubuntu-kernel-team is being unassigned from this bug report. Refer to https://wiki.ubuntu.com/KernelTeamBugPolicies for more information. Thanks.

This bug was reported a while ago but there hasn't been any recent comments or updates.
And I can not tell if this is an kernel-related or hardware-related issue.

If anyone has this issue. please test with lastest Jaunty kernel and see if the issue still exist.

Refer to http://www.ubuntu.com/testing/jaunty/beta
Please let us know.

This bug report is being closed because we received no response to the previous inquiry for information. Please reopen if this is still an issue in the current Ubuntu release, Jaunty Jackalope 9.04 - http://www.ubuntu.com/getubuntu/download. To reopen the bug, click on the current status under the Status column and change the status back to "New". Thanks.

I just had this same issue today :-(

I downloaded the 64 bit version of ubuntu 9.04 and tried loading live CD and full install on a machine with an AMD Athlon 64. Both brought me to this screen.

Thought you might like to know.

I just grabbed my old 8.10 install disk - 32 bit :-( - and it works like a charm.