Message-ID: <404C8CBB.1030008@nortelnetworks.com>
Date: Mon, 08 Mar 2004 10:09:47 -0500
From: Chris Friesen <cfriesen@nortelnetworks.com>
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To: arjanv@redhat.com
Cc: Andy Isaacson <adi@hexapodia.org>, Pavel Machek <pavel@ucw.cz>,
       linux-kernel@vger.kernel.org, Andrew Morton <akpm@osdl.org>
Subject: Re: Some highmem pages still in use after shrink_all_memory()?
References: <20040307144921.GA189@elf.ucw.cz>	 <20040307164052.0c8a212b.akpm@osdl.org>	 <20040308063639.GA20793@hexapodia.org> <1078738772.4678.5.camel@laptop.fenrus.com>
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Arjan van de Ven wrote:
>>Note that there are some applications for which it is a *bug* if an
>>mlocked page gets written out to magnetic media.  (gpg, for example.)
>>
> 
> mlock() does not guarantee things not hitting magnetic media, just as
> mlock() doesn't guarantee that the physical address of a page doesn't
> change.

The mlock() man page sure seems to hint that they do, by explicitly 
describing its use by high-security data processing as a way to keep the 
information from getting to disk.  There also seem to be a lot of 
references on the web about using mlock() in secure programming.

Something is not right...

Chris

-- 
Chris Friesen                    | MailStop: 043/33/F10
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