apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-alpha" pid=2392 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0

Fix:
$service apparmor teardown <=============works

https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/632696

==========Error=========

/var/log/syslog

Mar  3 20:10:39 localhost kernel: [4260864.783747] audit_printk_skb: 294 callbacks suppressed
Mar  3 20:10:39 localhost kernel: [4260864.783752] type=1400 audit(1488571839.231:3944): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-alpha" pid=2392 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0
Mar  3 20:10:39 localhost kernel: [4260864.789692] type=1400 audit(1488571839.235:3945): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-alpha" pid=2393 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0
Mar  3 20:10:39 localhost kernel: [4260864.797468] type=1400 audit(1488571839.243:3946): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-arm" pid=2394 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0
Mar  3 20:10:39 localhost kernel: [4260864.800058] type=1400 audit(1488571839.243:3947): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-arm" pid=2395 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0
Mar  3 20:10:39 localhost kernel: [4260864.800058] type=1400 audit(1488571839.243:3948): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-aarch64" pid=2396 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0
Mar  3 20:10:39 localhost kernel: [4260864.800058] type=1400 audit(1488571839.243:3949): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-aarch64" pid=2397 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0
Mar  3 20:10:39 localhost kernel: [4260864.800058] type=1400 audit(1488571839.243:3950): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-cris" pid=2398 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0
Mar  3 20:10:39 localhost kernel: [4260864.800058] type=1400 audit(1488571839.243:3951): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-cris" pid=2399 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0
Mar  3 20:10:39 localhost kernel: [4260864.800058] type=1400 audit(1488571839.243:3952): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-i386" pid=2400 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0
Mar  3 20:10:39 localhost kernel: [4260864.800058] type=1400 audit(1488571839.243:3953): apparmor="DENIED" operation="exec" profile="/usr/sbin/libvirtd" name="/usr/local/bin/qemu-system-i386" pid=2401 comm="libvirtd" requested_mask="x" denied_mask="x" fsuid=0 ouid=0