> commit 0fda6b403f0eca66ad8a7c946b3996e359100443
>
> Patch to fix huge number of wakeups reported due to recent changes in
> processor_idle.c. The problem was that the entry_method determination was
> broken due to one of the recent commits (bc71bec91f987) causing
> C1 entry to not to go to halt.
>
> http://lkml.org/lkml/2008/3/22/124
>
> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
> Signed-off-by: Len Brown <len.brown@intel.com>
OK, this fixes my issue with the massive amount of wakeups:
http://lkml.org/lkml/2008/4/24/70

However the CPU does not really go to C1 or C2 after applying this patch to 
the latest git kernel:

Cn                Avg residency       P-states (frequencies)
C0 (cpu running)        (99,4%)         1,80 Ghz     0,0%
C1                0,0ms ( 0,0%)         1,60 Ghz     0,0%
C2                0,0ms ( 0,6%)          800 Mhz   100,0%

- Daniel