Comment 3 for bug 107325

I have the same kernel problem. The machine is unstable, with random freezees every couple of days.

The problem:
- Machine is unstable. Max uptime is about two weeks. Hard freezees occur randomly, sometimes after less than day of use. Freeze is hard, nothing works: num lock does not change light, alt-ctrl-del does not work, picture is frozen on screen. Freeze also occurs when machine is not heavily loaded, even though heavy load seems to make it crash faster sometimes.
- To test the problem, I changed hard disk, re-installed Ubuntu (6.06 LTS -> 7.04). I checked that hard drive and motherboard temperature is acceptable. Memory passed test.
- Also, USB stopped to work after a kernel upgrade in Dapper (another bug).
- Machine is unstable in both 6.06 LTS and 7.04, even though I have only seen the error in dmesg of 7.07. Attached dmesg is from 7.04.

Some lines from dmesg:
Eeek! page_mapcount(page) went negative! (-1)
kernel BUG at mm/rmap.c:588!
Trying to fix it up, but a reboot is needed

Test setup:
- sudo lshw: CPU AMD Athlon(tm) XP 2200+, BIOS American Megatrends Inc. 07.00T (04/02/01), Motherboard ECS M848A
- uname -a: Linux *** 2.6.20-15-generic #2 SMP Sun Apr 15 07:36:31 UTC 2007 i686 GNU/Linux
- Ubuntu 7.04, fresh install.