Re: enforcing page color matches

[Masao Uebayashi <uebayasi%gmail.com@localhost>]

What happens if loaning is done?

Masao

On Wed, May 25, 2011 at 4:36 PM, Matt Thomas <matt%3am-software.com@localhost> 
wrote:
> I modified the mips pmap to drop into ddb if there was an attempt to map a 
> page with an incorrect page color (color(VA) != color(PA)).  Then using 
> UVMHIST I fixed each cause.  I can now boot a kernel on my matt-nb5-mips64 
> branch into sysinst with no bad color matches.  I'm sure I haven't found all 
> the cases but it's a big step forward.
>
> The diffs are relatively minor and are at 
> www.netbsd.org/~matt/uvm-color-diffs.txt for your viewing enjoyment.
>
> I'm using a MIPS 74K which needs strict page-coloring enforcement (4 colors 
> for its Icache and 2 colors for its Dcache) so this is important to me.  If 
> this can be enforced, the code to deal with bad colors can be removed and 
> that will greatly simplify the mips pmap code.
>
>