From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Egger <Christoph.Egger@amd.com>
Subject: machine check report on HVM startup
Date: Wed, 13 Aug 2008 13:48:05 +0200
Message-ID: <200808131348.05596.Christoph.Egger@amd.com>
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Hi,

When I launch  memtest as HVM guest, then Xen sends tons of VIRQ_MCA events
to the Dom0, although there occured NO correctable machine check errors.
When the Dom0 tries to fetch the error telemetry, then the

BUG_ON(mc_data.fetch_idx > mc_data.error_idx); in x86_mcinfo_getfetchptr()
in xen/arch/x86/cpu/mcheck/mce.c is hit. (x86_mcinfo_getfetchptr() only wor=
ks
if actually real error occured which is not the case.)

This looks to me, there's a non-public event channel using the same number
as VIRQ_MCA which fires when  launching memtest as HVM guest.

Christoph


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Operating System Research Center

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