Red Hat Bugzilla – Bug 176624
kernel panics "randomly"
Last modified: 2015-01-04 17:23:55 EST
From Bugzilla Helper: User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en) AppleWebKit/416.12 (KHTML, like Gecko) Safari/416.13 Description of problem: My machine has been stable until the past few weeks where the system will panic randomly. Nothing has changed in terms of hardware, and the kernel hasn't changed since 2005/10/28. The panic output is available at the URL specified in the ticket. Looking at the panic info, they reference vgacon a bit. The only related change to the console that I can think of (there's no console connected by default) is that I added "/usr/bin/setterm -blank 0" to rc.local, just in case a crash happened and I didn't have the serial console connected, I wouldn't have to worry about the video console being blank. System hardware: 2x Opteron 246 (2GHz), 2GB ECC RAM. Please let me know if you need any other information. Version-Release number of selected component (if applicable): kernel-smp-2.6.12-1.1381_FC3 How reproducible: Didn't try Steps to Reproduce: Unknown. The system runs for several days, then panics. From "last": reboot system boot 2.6.12-1.1381_FC Tue Dec 27 11:51 (03:56) reboot system boot 2.6.12-1.1381_FC Thu Dec 22 13:23 (5+02:25) reboot system boot 2.6.12-1.1381_FC Sat Dec 3 11:39 (24+04:09) [...] wtmp begins Thu Dec 1 08:30:15 2005 Additional info:
This was fixed upstream post 2.6.12, but I'm not sure exactly when, and how. There were 1-2 reports of this against FC4, but since the last few rebases to newer upstream releases, the problem got fixed. The problem with isolating the change responsible for fixing this is that so much has changed, and it's unlikely to be a small diff, but more likely a series of reworked core vm functions. Backporting such changes is very risky, and could even cause more problems than we currently have. As FC3 is nearing end of life, the only bugs that are likely to get fixed there over the few weeks remaining are security issues. But upgrading to Fedora Core 4 now should have this fixed in the current update kernel.
Hrm. Ok. Do you know of any workarounds for this issue then? Is the problem specifically related to disabling screen blanking? I've been thinking about upgrading to FC4, but haven't had time to do it up to now. Are there any known issues running the FC4 kernel on an FC3 machine? I'd assume I also would have to upgrade things like kernel-utils, lvm, etc? Thanks.
I don't think it's related to blanking. It's core memory management internals hitting some corner case, and losing its marbles trying to make sense of things. it'd probably be a nightmare dependancy mess to put an FC4 kernel on FC3. At the least, you'd need a new udev, hotplug, initscripts, alsa-utils/lib, and all the related dependancies that those drag in. Debugging any other issues that crop up on 'hybrid' installs like this is near impossible. The 'upgrade' option in the installer also fixes up a bunch of other things that a 'yum update' won't do. (Like removing obsolete entries from your modprobe.conf for one to give you an example). (The mess of updated dependancies is also why there's no kernel newer than 2.6.12 for FC3 -- Given it's so close to EOL, it'd be a race against time to get userspace back in ship-shape again. Rebasing to a newer upstream release is really painful in this regard, because a lot of the time, we don't realise we need newer package Y until /after/ we've shipped a kernel update, and broken previously working setups.