Description of problem:
In my efforts to build a scratch image for testing other BZ in preparation for 6.4.z, I hit a deadlock that prevented the RPM from completing 'make check'.  To date, we've been lucky that brew has not hit this same deadlock, but since we know the fix, and since the fix is non-invasive (it touches _only_ the testsuite, for the 'make check' portion of making the rpm, and does not affect installed binaries), having it backported to 6.4.z would ensure that we don't hit the race in a future brew build.

Version-Release number of selected component (if applicable):
libvirt-0.10.2-18.el6_4.3

How reproducible:
< 10%

Steps to Reproduce:
1. rpmbuild --rebuild libvirt-0.10.2-18.el6_4.3.srpm
2.
3.
  
Actual results:
Rarely, the build will hang during 'make check', with output resembling:
PASS: qemumonitortest
TEST: qemumonitorjsontest
      ....
I had to ctrl-c to kill the hung test, which in turn killed the build.

Expected results:
Testsuite shouldn't hang.

Additional info:
Fixed upstream:
commit e25a32f3da801207a5009c12747f3d155ac4c43a
Author: Peter Krempa <pkrempa>
Date:   Mon Nov 12 11:34:41 2012 +0100

    tests: Fix qemumonitorjsontest deadlock when the machine is under load
    
    When doing the qemumonitorjsontest on a machine under heavy load the
    test tends to deadlock from time to time. This patch adds the hack to
    break the event loop that is used in virsh.