Re: Right place to discuss probable issues in libobjc2?

[Derek Fawcus]

On Wed, Jan 22, 2014 at 02:18:05pm -0800, David Chisnall wrote:
> 
> The code in question needs to make the same memory in two different places 
> with different permissionss
> (to enforce W^X mappings).

Yeah - I missed that second mmap() the firt time I read it...

>  Using anonymous maps as this code does, does not permit that.

One other thing that sprung to mind about the dual mapping was
with systems having virtual mapped caches.  I've a vague memory
of issues with this sort of game on such systems.

However,  its probably moot given how most systems these days
have physically mapped caches.

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