machine check report on HVM startup

[Christoph Egger <Christoph.Egger@amd.com>]

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 works
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


-- 
AMD Saxony, Dresden, Germany
Operating System Research Center

Legal Information:
AMD Saxony Limited Liability Company & Co. KG
Sitz (Geschäftsanschrift):
   Wilschdorfer Landstr. 101, 01109 Dresden, Deutschland
Registergericht Dresden: HRA 4896
vertretungsberechtigter Komplementär:
   AMD Saxony LLC (Sitz Wilmington, Delaware, USA)
Geschäftsführer der AMD Saxony LLC:
   Dr. Hans-R. Deppe, Thomas McCoy