I'm running Xfce on Fedora 17. Every so often (daily?) I loose the 
keyboard. Mouse works fine.  I've been trying to discover what 
process is running before loss but not after. The only processes that 
I've been able to identify are kworkers.

Are there any suggestions as to what the cause might be? 

The only processes that I can identify from ps before and after are 
kworkers, most often (but not exclusively) is [kworker/0:2] Is there 
any way to identify what the kworkers are assigned to? (The problem has 
continued over several kernels)

Logout-login cures the problem. 

Thanks.