Invalidate Data Cache from User Space

Josh Boyer jwboyer at
Tue Nov 10 12:15:47 EST 2009

On Mon, Nov 09, 2009 at 11:10:42AM -0700, Jonathan Haws wrote:
>What is happening is the dcbi instruction will fail.  I get an Illegal Instruction message on the console and my program exits.
>Is there a reason I cannot call dbci from a user space application, or is there something wrong in my code?  Even better, is there a working and tested function that I can call from user space to invalidate a portion of the data cache?

dcbi is a priviledged instruction on 4xx.  You can only execute it from
supervisor mode (kernel).


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