Re: [PATCH] DEV: zero: use correct pgprot for zeromapping

From: Imre Deak
Date: Sat Feb 10 2007 - 05:04:01 EST


On Sat, Feb 10, 2007 at 09:39:54AM +0000, Russell King wrote:
> On Sat, Feb 10, 2007 at 11:15:21AM +0200, Imre Deak wrote:
> > Instead of PAGE_COPY use the pgprot bits established already at
> > original mapping time of the VMA. This will also include any
> > architecture specific bits setup through protection_map.
> > zeromap_page_range will take care of COW'ing the passed pgprot.
>
> NAK. What if PAGE_COPY is used elsewhere and ends up accidentally
> allowing write access?

Or rather, result in the bogus global mapping. True.

>
> I think the right solution is to make PAGE_COPY a variable in the same
> way that PAGE_KERNEL is, and adjust it as appropriate.

Ok, and also at least PAGE_SHARED and PAGE_READONLY I assume.

--Imre
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