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Date: Thu, 29 Jun 2006 20:48:17 -0700
From: "Ulrich Drepper" <drepper@gmail.com>
To: "Arjan van de Ven" <arjan@infradead.org>
Subject: Re: make PROT_WRITE imply PROT_READ
Cc: "Pavel Machek" <pavel@ucw.cz>, "Jason Baron" <jbaron@redhat.com>,
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On 6/29/06, Arjan van de Ven <arjan@infradead.org> wrote:
> the thing is.. you can say EXACTLY the same about PROT_EXEC.. not all
> processors support enforcing that.. so should we just always imply
> PROT_EXEC as well?

There is a fundamental difference: not setting PROT_EXEC has no
negative side effects.  You might be able to execute code and it just
works.

With PROT_READ this is not the case, there _are_ side effects which are visible.