Between kernel 2.6.18-173.el5 and 2.6.18-179.el5 hibernation stopped working on my Thinkpad X200s. I am using x86_64. It fails also -180.el5 and -182.el5.

The problem is that it tries to hibernate for some time and after 120 secs comes back out of hibernation. Which can be dangerous for people that expected it to work and put it inside a bag :-)

The output from the kernel when it fails is consistently:

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Dec 21 05:52:11 moria NetworkManager: <info>  (wlan0): cleaning up...
Dec 21 05:52:11 moria NetworkManager: <info>  (wlan0): taking down device.
Dec 21 05:52:15 moria kernel: Disabling non-boot CPUs ...
Dec 21 05:52:15 moria kernel: kvm: disabling virtualization on CPU1
Dec 21 05:52:15 moria kernel: CPU 1 is now offline
Dec 21 05:52:15 moria kernel: SMP alternatives: switching to UP code
Dec 21 05:54:15 moria kernel: CPU1 is down
Dec 21 05:54:15 moria kernel: Stopping tasks: =======================================================================================================
Dec 21 05:54:15 moria kernel:  stopping tasks timed out after 120 seconds (1 tasks remaining):
Dec 21 05:54:15 moria kernel:   khungtaskd
Dec 21 05:54:15 moria kernel: Restarting tasks...<6> Strange, khungtaskd not stopped
Dec 21 05:54:15 moria gnome-power-manager: (dag) Resuming computer
Dec 21 05:54:15 moria NetworkManager: <info>  Waking up...
Dec 21 05:54:15 moria NetworkManager: <info>  (eth0): now managed
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