[PATCH] network: Fix a race condition when shutdown & start vm at the same time

[Bingsong Si <owen.si@xxxxxxxxx>]

when shutdown vm, the qemuProcessStop cleanup virtual interface in two steps:
1. qemuProcessKill kill qemu process, and vif disappeared
2. ovs-vsctl del-port from the brige

if start a vm in the middle of the two steps, the new vm will reused the vif,
but removed from bridge by step 2

Signed-off-by: Bingsong Si <owen.si@xxxxxxxxx>
---
 src/qemu/qemu_process.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index d36088ba98..706248815a 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -7483,9 +7483,11 @@ void qemuProcessStop(virQEMUDriverPtr driver,
             if (vport->virtPortType == VIR_NETDEV_VPORT_PROFILE_MIDONET) {
                 ignore_value(virNetDevMidonetUnbindPort(vport));
             } else if (vport->virtPortType == VIR_NETDEV_VPORT_PROFILE_OPENVSWITCH) {
-                ignore_value(virNetDevOpenvswitchRemovePort(
-                                 virDomainNetGetActualBridgeName(net),
-                                 net->ifname));
+                virMacAddr mac;
+                if (virNetDevGetMAC(net->ifname, &mac) < 0 ||  !virMacAddrCmp(&mac, &net->mac))
+                    ignore_value(virNetDevOpenvswitchRemovePort(
+                                     virDomainNetGetActualBridgeName(net),
+                                     net->ifname));
             }
         }
 
-- 
2.18.2