Message-ID: <20011121143726.16204.qmail@web13303.mail.yahoo.com>
Date: Wed, 21 Nov 2001 06:37:26 -0800 (PST)
From: Joerg Pommnitz <pommnitz@yahoo.com>
Subject: Re: copy to suer space
To: linux-kernel@vger.kernel.org
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Sender: linux-kernel-owner@vger.kernel.org

Nick LeRoy <nleroy@cs.wisc.edu> wrote:

 > Linux executables are "demand paged".  What this means is that they are

 > loaded as they are "page faulted" in.  If low on memory, the kernel 
 > may, at it's discression, discard text pages at any time.  When a 
 > discarded page is referenced, a page fault occurs, and the page is re-
 > loaded from the executable.  They are *never* written out to swap 
 > space.  The kernel fully expects the text file and the text memory 
 > pages to not be modified during execution.

Clean pages are never written to swap space. If the page is dirty, it's
just another data page. If it were otherwise, non-PIC shared libraries
that require fixups from the dynamic linker would not work.

Regards
  Joerg


=====
-- 
Regards
       Joerg


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