commit 5ea2abb3bfd552175dc2dfcc295fde3fbf17fc37
Author: Jim Fehlig <jfehlig@suse.com>
Date:   Fri Aug 24 15:38:14 2018 -0600

    libxl: join with thread receiving migration data
    
    It is possible the incoming VM is not fully started when the finish
    phase of migration is executed. In libxlDomainMigrationDstFinish,
    wait for the thread receiving the VM to complete before executing
    finish phase tasks.
    
    Signed-off-by: Jim Fehlig <jfehlig@suse.com>
    ACKed-by: Michal Privoznik <mprivozn@redhat.com>

Index: libvirt-4.7.0/src/libxl/libxl_domain.h
===================================================================
--- libvirt-4.7.0.orig/src/libxl/libxl_domain.h
+++ libvirt-4.7.0/src/libxl/libxl_domain.h
@@ -65,6 +65,7 @@ struct _libxlDomainObjPrivate {
     /* console */
     virChrdevsPtr devs;
     libxl_evgen_domain_death *deathW;
+    virThreadPtr migrationDstReceiveThr;
     unsigned short migrationPort;
     char *lockState;
 
Index: libvirt-4.7.0/src/libxl/libxl_migration.c
===================================================================
--- libvirt-4.7.0.orig/src/libxl/libxl_migration.c
+++ libvirt-4.7.0/src/libxl/libxl_migration.c
@@ -297,9 +297,9 @@ libxlMigrateDstReceive(virNetSocketPtr s
     libxlMigrationDstArgs *args = opaque;
     virNetSocketPtr *socks = args->socks;
     size_t nsocks = args->nsocks;
+    libxlDomainObjPrivatePtr priv = args->vm->privateData;
     virNetSocketPtr client_sock;
     int recvfd = -1;
-    virThread thread;
     size_t i;
 
     /* Accept migration connection */
@@ -318,7 +318,10 @@ libxlMigrateDstReceive(virNetSocketPtr s
      * the migration data
      */
     args->recvfd = recvfd;
-    if (virThreadCreate(&thread, false,
+    VIR_FREE(priv->migrationDstReceiveThr);
+    if (VIR_ALLOC(priv->migrationDstReceiveThr) < 0)
+        goto fail;
+    if (virThreadCreate(priv->migrationDstReceiveThr, true,
                         libxlDoMigrateDstReceive, args) < 0) {
         virReportError(VIR_ERR_OPERATION_FAILED, "%s",
                        _("Failed to create thread for receiving migration data"));
@@ -557,7 +560,6 @@ libxlDomainMigrationDstPrepareTunnel3(vi
     libxlDriverPrivatePtr driver = dconn->privateData;
     virDomainObjPtr vm = NULL;
     libxlMigrationDstArgs *args = NULL;
-    virThread thread;
     bool taint_hook = false;
     libxlDomainObjPrivatePtr priv = NULL;
     char *xmlout = NULL;
@@ -617,7 +619,10 @@ libxlDomainMigrationDstPrepareTunnel3(vi
     args->nsocks = 0;
     mig = NULL;
 
-    if (virThreadCreate(&thread, false, libxlDoMigrateDstReceive, args) < 0) {
+    VIR_FREE(priv->migrationDstReceiveThr);
+    if (VIR_ALLOC(priv->migrationDstReceiveThr) < 0)
+        goto error;
+    if (virThreadCreate(priv->migrationDstReceiveThr, true, libxlDoMigrateDstReceive, args) < 0) {
         virReportError(VIR_ERR_OPERATION_FAILED, "%s",
                        _("Failed to create thread for receiving migration data"));
         goto endjob;
@@ -1291,6 +1296,13 @@ libxlDomainMigrationDstFinish(virConnect
     virObjectEventPtr event = NULL;
     virDomainPtr dom = NULL;
 
+    if (priv->migrationDstReceiveThr) {
+        virObjectUnlock(vm);
+        virThreadJoin(priv->migrationDstReceiveThr);
+        virObjectLock(vm);
+        VIR_FREE(priv->migrationDstReceiveThr);
+    }
+
     virPortAllocatorRelease(priv->migrationPort);
     priv->migrationPort = 0;