From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: RE: trap/interrupt gate for hypercall
Date: Wed, 16 May 2007 16:23:30 +0200
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References: <C2706847.7706%Keir.Fraser@cl.cam.ac.uk>
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To: Jinsong Liu <jinsong.liu@intel.com>
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>Enter Xen on hypercall, immediately take an interrupt, on return from
>interrupt %es faults on reload. How do we propagate this bad segment
>   --> the problem is when return from interrupt how %es faults on reload
>	except interrupt handler purposely modify kernel stack? --> =
example?

By the guest modifying the referenced descriptor from another vCPU.

>register value to the guest via the failsafe callback handler from this
>context? The bad %es is not yet saved on the outer context's stack frame.

Jan