[ltp] Deep CPU Cx states

[Daniel Skorka]

On Fri, Jul 14, 2006 at 05:40:31PM +0200, Laurent Gilson wrote:
> You need to have a very limited board (or no drivers loaded). These  
> http://www.commell.com.tw/Product/COM%20Express/CES-470.htm reach C6.
> 
> The kernel just tries to prevent data loss. As soon as another bus master  
> beside the CPU is detected all lower states are blocked. Which is a GOOD  
> THING (tm). Cache corruption is nearly impossible to fix and very hard to  
> debug. On laptops C4, maybe C5 is the best you can expect.

How exactly does cache corruption occur in C5 and lower? I would have
thought that these states were defined in such a way as to be useful...

Daniel