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Subject: Re: Security question: "Text file busy" overwriting executables but
	not shared libraries?
From: Xavier Bestel <xavier.bestel@free.fr>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@transmeta.com>,
        Jamie Lokier <lk@tantalophile.demon.co.uk>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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	 <m1lmiera0x.fsf@frodo.biederman.org>
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Date: 14 Oct 2001 10:17:24 +0200
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le dim 14-10-2001 ? 08:49, Eric W. Biederman a ?crit :
> Also read-with-PAGE_COPY has some really interesting implications for the
> page out routines.  Because anytime you start the page out you have to
> copy the page.  Not exactly when you want to increase the memory presure.
> And not at all suitable for shared libraries.

I didn't understood very well why you would want to swap out a page
marked PAGE_COPY ? Doesn't it make sense to special-case it and just
leave it "in the file", as long as it's untouched ?

	Xav

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