Yelläks /ˈyæl•eks/

After updating the kernel of my Debian distribution (Lenny) from 2.6.24 to 2.6.26 random freezes occurred. No message has been left by the kernel (exept “– MARK –”) in syslog and nothing could give a hint to what have might caused the freeze. First the mouse got stuck on the screen and jumped a few times. After one or two seconds nothing worked anymore and the only way to exit this was to hold the power button for a long time. I had the feeling that after waking up from Suspend to RAM the chances that the computer will freeze, were definitely higher. The problem vanished after switching back to the fortunately not-uninstalled 2.6.24 kernel. In some forums I read about a bug in the latest version coming from the High Precicion Event Timer (hpet) and that this timer is rarly used. Please correct me, if I wrong. I switched it off and since then the freezes have not occurred again so far.

To switch of the hpet, add the option “hpet=disable” at the appropriate place in /boot/grub/menu.list so that an entry looks like this:

title	Debian GNU/Linux, kernel 2.6.26-1-686
root	(hd0,1)
kernel	/boot/vmlinuz-2.6.26-1-686 root=/dev/sda2 ro quiet hpet=disable
initrd	/boot/initrd.img-2.6.26-1-686

EDIT (18/10/08):
After a few days without any problem, it reoccurred suddenly. But this time instead of freezing, the CPU fan turned on and within 5 seconds, the box was switched off. ZIPP – OFF. Just like that. It was very annoying, since it occurred randomly again and I lost the data of the current work. I would say, kernel 2.6.26 is not recommended on the Bullman laptop, therefore I compiled 2.6.27 from the kernel sources of kernel.org two days back (this kernel is not in the Debian repository). So far I have not experienced any problem.