From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH] xen: Disable REP MOVSD optimization if
 introspection is active
Date: Mon, 27 Oct 2014 10:50:43 +0000
Message-ID: <544E2383.1020604@citrix.com>
References: <1414406263-11421-1-git-send-email-rcojocaru@bitdefender.com>
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On 27/10/14 10:37, Razvan Cojocaru wrote:
> REP MOVSD emulation is optimized to write several pages at once
> if possible. While this is a very good thing in general, it
> can interfere with a memory introspection application's ability
> to detect suspect behaviour, since it supresses potentially
> telling future page faults. This patch disables the optimization,
> gated on introspection being active for the domain.

An individual rep_movs() call should only optimise to within the current
page, then break back out to the emulator when passing the page boundary.

How does this suppress pagefaults?

~Andrew