Using Kubuntu 7.10 on Dell Latitude D630. I've noticed an issue with hibernate not restoring after about an hour or more of sleep. If I restore within 5 mintues, no problems. Wait about an hour, and it does not restore. The system just reboots. However, if you change the filesystem, i.e. touching a new file, and reboot, the saved session from the previous hibernation comes back on the subsequent reboot. This really hosed up my JFS filesystem. I think it may be what's caused my kernel panic and inability to boot the system.
I am using JFS and LVM. The swap partition is on a LVM logical partition. As an aside, is it necessary to specify the "resume=" kernel option? I don't seem to be able to modify the "defoptions" line in menu.lst without update-grub erasing it.
Okay, it has happened again. This time, my partition is more simple: /boot, /, /home, and swap. No LVM. I hibernated the computer. Put it back into the port replicator. Turned the computer back on, and a new session came up. On reboot, the hibernated session came back. File system (JFS) was still corrupted.