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To: "Mark W. Krentel" <krentel@dreamscape.com>
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Date: Wed, 14 Apr 2004 15:34:12 +1000
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Subject: Re: kern/64573: mmap with PROT_NONE, but still could be read 
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> The same bug happens mmap()-ing a file with PROT_WRITE, you still get
> read access.  In this case, PROT_NONE was just the simplest way to
> demonstrate the bug.

IIRC, in the original mmap man page lo these many years ago, there was a
proviso about "hardware willing" (with the "PROT_WRITE implies PROT_READ" 
case explicitly mentioned).  

I wonder if the implementation still favours efficient implementation over
semantic correctness, and if this proviso might be noted in the man page?
Is it even possible to implement PROT_WRITE&~PROT_READ or PROT_NONE on i386?