Re: mprotect pgprot handling weirdness

From: Benjamin Herrenschmidt
Date: Tue Apr 06 2010 - 01:43:53 EST


On Tue, 2010-04-06 at 15:09 +1000, Benjamin Herrenschmidt wrote:
> (*) Right now it's near impossible to add arch specific PROT_* bits to
> mmap/mprotect for fancy things like cachability attributes, or other
> nifty things like reverse-endian mappings that we have on some embedded
> platforms, I'm investigating ways to better separate vm_page_prot from
> vm_flags so some PROT_* bits can go straight to the former without
> having to be mirrored in some way in the later.

The other (easier) option is to make the vm flags always 64-bit and
reserve a range of bits here for the arch to use but I suppose there's
going to be unhappiness about that one :-)

Cheers,
Ben.


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