Why flush_cache_all() not including flushing L2 cache if the system has L2 cache?

[Peter Chen]

Russell King - ARM Linux wrote:
> On Mon, Nov 02, 2009 at 10:32:13AM +0800, Peter Chen wrote:
>> I met a problem if the address is first used by cachable, then  
>> uncachable. After that, the address will be filled with cachable value
>> after that L2 cache line is evicted.
> 
> What _exactly_ are you trying to do?  Why are you apparantly mapping
> something in as cacheable, and then making it uncacheable?
> 
This is 3rd party released code

This problem happens at device driver wants to alloc uncachable memory, 
but it doesn't alloc it using dma_ API.

-- 
Best regards,
Peter Chen