[PATCH 2/6] 8xx: get rid of _PAGE_HWWRITE dependency in MMU.
benh at kernel.crashing.org
Thu Oct 8 11:04:56 EST 2009
> Yes it does. If one adds HWEXEC it will fail, right?
Why ? We can just filter out DSISR, we don't really care why it failed
as long as we know whether it was a store or not.
> Also this count as a read and you could easily end up
> in the protection case(in 2.4 you do)
I'm not sure what you mean by "the protection case" Again, the C code
> hey, I think you have to show how then :) I am not
> good at ppc shift, mask, rotate insn.
They are so fun ! :-0
> > > Because if you go to C with a protection fault, you are in trouble.
> > Why ?
> In 2.4 you end up in read protection fault an get a SEGV back :)
We probably should ignore the DSISR bits then. So it just goes to
generic C code which then fixes up ACCESSED etc... and returns.
> Now I only handle DIRTY and the rest in C. Figured it is
> much faster and really simplie now, stay tuned.
You should not even have to handle DIRTY at all in asm. At least in 2.6.
I can't vouch for what 2.4 generic code does... You should really port
your board over :-)
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