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Re: HEADS UP: user address 0 mapping disabled

On Sat, 20 Feb 2010, Matthias Drochner wrote:

> So I've just changed the kernel to disallow user
> mappings of address 0 in the default case. This
> affects use of mmap() and execution of binaries
> which want to load text or data into the first
> page. Native NetBSD code is not affected, so in

Are you disallowing all mappings or just R/W mappings?  Since the problem 
only occurs when you write data to page zero R/O mappings should be 
allowed, especially sine they can be used by the compiler to optimize 
pointer chasing operations.


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