Comment 2 for bug 1508405

OK, I just git-bisected and it found the following commit to probably cause the problem:
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355023f2010c4df619d88a0dd7012b4b9c74c12c is the first bad commit
commit 355023f2010c4df619d88a0dd7012b4b9c74c12c
Author: Paolo Bonzini <email address hidden>
Date: Thu Jun 18 18:30:52 2015 +0200

    pc: add SMM property

    The property can take values on, off or auto. The default is "off"
    for KVM and pre-2.4 machines, otherwise "auto" (which makes it
    available on TCG or on new-enough kernels).

    Acked-by: Michael S. Tsirkin <email address hidden>
    Signed-off-by: Paolo Bonzini <email address hidden>

:040000 040000 28b1de64871e1baa3aaad155f22f7c44d5fdc94f 77265bdd62664d15d8ad6ef3364aeb284d030486 M hw
:040000 040000 8b933a2739a2dccb0b5e28ab3ce20e2bb703780b a8d444cb27fbd54b0b9a7bd9997db355da15763e M include
:040000 040000 1acb81aecaf50f2d313b33f2b61a24f7f0bd6f07 726899e7ae70d04dd9acd7000fa1c5dee715da3e M target-i386
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The script I ran after each bisection step:

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make clean
PREFIX=$PWD/localinstall
export ARFLAGS="rv"
  # http://permalink.gmane.org/gmane.comp.emulators.qemu/238740
  export CFLAGS+=' -fPIC'
  # gtk gui breaks keymappings at the moment
  ./configure --prefix=$PREFIX --sysconfdir=/etc --audio-drv-list='pa alsa sdl' \
              --python=/usr/bin/python2 --smbd=/usr/bin/smbd \
              --enable-docs --libexecdir=$PREFIX/lib/qemu \
              --disable-gtk --enable-linux-aio --enable-seccomp \
              --enable-spice --localstatedir=/var \
              --enable-tpm \
              --enable-modules --enable-{rbd,glusterfs,libiscsi,curl}
  make V=99 -j9 && ./x86_64-softmmu/qemu-system-x86_64 --enable-kvm
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Hope this helps!