GMP 6.0.0a on AMD A8-6600K

[tg at gmplib.org]

Kevin Buckley <kevin.m.buckley at gmail.com> writes:

  As noted in the Xen package listings provided, I believe it's the latest
  available for the Ubuntu 12.04 distribution.
  
Version?  The command "xl info" should give you that.

  Note, though I am sure you will have, that the snapshot's configure, inside
  a Xen environment, reports the Host type as
  
    Host type:         piledrivernoavx-unknown-linux-gnu
  
  whereas in a non-Xen environment, it reports
  
    Host type:         piledriver-unknown-linux-gnu
  
  so is recognising (?) an AVX-based distinction.
  
This might be a problem, but it might not.  GMP appends noavx if it
detect a CPU which does normally support AVX running a kernei which
cannot context switch AVX registers properly.

It is not inconceivable that your non-Xen kernel is to old to support
AVX while your guest kernel supports it.  (I'd assume Xen also needs to
support it.)
  
We need you to check the culprit instruction with gdb, as suggested.
Then we can go from there.
  

-- 
Torbjörn
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