migration: Allow to suppress vmdesc submission

We now always send a JSON blob describing the migration file format as part
of the migration stream. However, some tools built around QEMU have proven
to stumble over this.

This patch gives the user the chance to disable said self-describing part of
the migration stream. To disable vmdesc submission, just add

  -machine suppress-vmdesc=on

to your QEMU command line.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Juan Quintela <quintela@redhat.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/hw/core/machine.c b/hw/core/machine.c
index e3a3e2ab73..cb1185ada4 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -254,6 +254,20 @@ static void machine_set_iommu(Object *obj, bool value, Error **errp)
     ms->iommu = value;
 }
 
+static void machine_set_suppress_vmdesc(Object *obj, bool value, Error **errp)
+{
+    MachineState *ms = MACHINE(obj);
+
+    ms->suppress_vmdesc = value;
+}
+
+static bool machine_get_suppress_vmdesc(Object *obj, Error **errp)
+{
+    MachineState *ms = MACHINE(obj);
+
+    return ms->suppress_vmdesc;
+}
+
 static int error_on_sysbus_device(SysBusDevice *sbdev, void *opaque)
 {
     error_report("Option '-device %s' cannot be handled by this machine",
@@ -377,6 +391,12 @@ static void machine_initfn(Object *obj)
     object_property_set_description(obj, "iommu",
                                     "Set on/off to enable/disable Intel IOMMU (VT-d)",
                                     NULL);
+    object_property_add_bool(obj, "suppress-vmdesc",
+                             machine_get_suppress_vmdesc,
+                             machine_set_suppress_vmdesc, NULL);
+    object_property_set_description(obj, "suppress-vmdesc",
+                                    "Set on to disable self-describing migration",
+                                    NULL);
 
     /* Register notifier when init is done for sysbus sanity checks */
     ms->sysbus_notifier.notify = machine_init_notify;