From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: [PATCH] x86: clear guest's EFLAGS.RF after
	emulating instructions
Date: Tue, 19 Jun 2007 11:09:55 +0100
Message-ID: <4677C793.76E4.0078.0@novell.com>
References: <4677C3AE.76E4.0078.0@novell.com>
	<C29D67AB.10DEB%Keir.Fraser@cl.cam.ac.uk>
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: quoted-printable
Return-path: <xen-devel-bounces@lists.xensource.com>
In-Reply-To: <C29D67AB.10DEB%Keir.Fraser@cl.cam.ac.uk>
Content-Disposition: inline
List-Unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xensource.com>
List-Help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-Subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
Sender: xen-devel-bounces@lists.xensource.com
Errors-To: xen-devel-bounces@lists.xensource.com
To: Keir Fraser <Keir.Fraser@cl.cam.ac.uk>, xen-devel@lists.xensource.com
List-Id: xen-devel@lists.xenproject.org

>You set EFLAGS.RF in a few places when injecting #PF. Why would you do =
that?
>It isn't Xen's job to set that flag ever afaics, and since the original =
trap
>into Xen was not due to #DB you're not avoiding an infinite loop.

This is only in handle_mmio() where I cleared the flag earlier - since #PF =
has lower
priority than #DB, .RF must have been set when the exception was reported, =
and
hence I must re-set it when forwarding the exception.

Jan