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Re: [Xen-devel] [PATCH] x86: clear guest's EFLAGS.RF after emulating ins

To: "Keir Fraser" <Keir.Fraser@xxxxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] x86: clear guest's EFLAGS.RF after emulating instructions
From: "Jan Beulich" <jbeulich@xxxxxxxxxx>
Date: Tue, 19 Jun 2007 11:09:55 +0100
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>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


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