Randomly, but not later than after 10 hours of work, the laptop freezes. Just freezes. Knowing that not all hardware errors are reported back to the user I tried the netconsole. Unfortunately the netconsole also didn't output anything at the time of freeze.
The «BUSIER» combination also doesn't work when system hangs.
The only correlation I've found is that usually, on next powering up (after forced powering off) the laptop consumes 10W more power. But I suspect it might by a concidence; this behaviour is not limited to the times, when system was powered on after the freeze. After 1.5 (on average) times rebooting, the power consumption is back to normal.
- The problem persists across any of kernel 3.5.x - 3.7.1.
- The problem persists with WiFi turned off.
- The laptop works just fine with Windows XP (I've never tried 7 on it)
- I never tried 32-bit Linux on this machine.
- I use both VirtualBox and VMWare. The hanging happens also when no virtual machine is powered on, but I know that both programs insert some kernel modules.
- I use btrfs, dm-crypt, Huwavei E220 modem, bluetooth and a ton of other stuff typical for a notebook.
...
- I will paste whatever log/configuration file that you deem necessary.
What is the next course of action for troubleshooting this freezing problem?
Knowing exactly nothing about the causes of the problem, there is almost infinite number of combinations to try. But maybe some of you are more experienced with debugging hardware and can suggest some usual suspects?
UPDATE:
Suspecting that the non-standard Ubuntu mainline kernel is a culprit I did reinstall the whole system, this time with Mint14 which is based on Ubuntu 12.10, which in turn is based on the 3.5.x kernel family. Unfortunately, the same problem :-(
UPDATE 2:
The distribution of hanging events seems to be non-Poisson (i.e. sometimes more frequently, sometimes less frequently), but so far I don't know how to correlate it with any type of event. It happens both when laptop is used interactively or not. It happens both when the memory is used (and the system page is used - zram in my case) and when the memory is only 30% used.
noirqdebug
as kernel-option. This will keep the system from inactivating IRQs it thinks that are not in use. I had this funny effect on some servers - where a CDROM and a NIC were on the same IRQ and the system shut down the IRQ-handler after the CDROM was idle...noirqdebug
... With the very new 3.7.1 kernel.