Comment 7 for bug 1643911

New occurrence, with a slightly different signature:
http://logs.openstack.org/04/426604/3/gate/gate-tempest-dsvm-neutron-full-ubuntu-xenial/708771d/logs/syslog.txt.gz#_Feb_01_11_47_53

Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: *** Error in `/usr/sbin/libvirtd': realloc(): invalid next size: 0x000056108d7a7450 ***
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: ======= Backtrace: =========
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /lib/x86_64-linux-gnu/libc.so.6(+0x777e5)[0x7f48cb75c7e5]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /lib/x86_64-linux-gnu/libc.so.6(+0x82a5a)[0x7f48cb767a5a]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /lib/x86_64-linux-gnu/libc.so.6(realloc+0x179)[0x7f48cb768c89]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /usr/lib/x86_64-linux-gnu/libvirt.so.0(virReallocN+0x43)[0x7f48cc1362f3]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /usr/lib/libvirt/connection-driver/libvirt_driver_qemu.so(+0x7d0f9)[0x7f48a78ac0f9]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /usr/lib/libvirt/connection-driver/libvirt_driver_qemu.so(+0x933dc)[0x7f48a78c23dc]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /usr/lib/x86_64-linux-gnu/libvirt.so.0(virEventPollRunOnce+0x7b3)[0x7f48cc154393]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /usr/lib/x86_64-linux-gnu/libvirt.so.0(virEventRunDefaultImpl+0x41)[0x7f48cc152c01]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /usr/lib/x86_64-linux-gnu/libvirt.so.0(virNetDaemonRun+0x14d)[0x7f48cc29eb4d]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /usr/sbin/libvirtd(+0x14407)[0x56108cdf5407]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf0)[0x7f48cb705830]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: /usr/sbin/libvirtd(+0x14bd9)[0x56108cdf5bd9]
Feb 01 11:47:53 ubuntu-xenial-osic-cloud1-s3700-7053530 libvirtd[16665]: ======= Memory map: ========