[libvirt PATCH 04/80] qemu: Enable migration events only when disabled

[Jiri Denemark <jdenemar@xxxxxxxxxx>]

When connecting to a QEMU monitor, we always try to enable migration
events, but this is an invalid operation during migration. Thus
reconnecting to a domain with active migration would fail. Let's check
the state of migration events capability and only try to enable it when
it is disabled.

Signed-off-by: Jiri Denemark <jdenemar@xxxxxxxxxx>
---
 src/qemu/qemu_migration_params.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/src/qemu/qemu_migration_params.c b/src/qemu/qemu_migration_params.c
index 34416f89be..ed2d9ac103 100644
--- a/src/qemu/qemu_migration_params.c
+++ b/src/qemu/qemu_migration_params.c
@@ -1391,13 +1391,16 @@ qemuMigrationCapsCheck(virQEMUDriver *driver,
     g_autoptr(virBitmap) migEvent = NULL;
     g_autoptr(virJSONValue) json = NULL;
     g_auto(GStrv) caps = NULL;
+    g_autoptr(virBitmap) capState = NULL;
+    g_autoptr(virBitmap) enabled = virBitmapNew(QEMU_MIGRATION_CAP_LAST);
     char **capStr;
+    size_t i;
     int rc;
 
     if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0)
         return -1;
 
-    rc = qemuMonitorGetMigrationCapabilities(priv->mon, &caps, NULL);
+    rc = qemuMonitorGetMigrationCapabilities(priv->mon, &caps, &capState);
 
     qemuDomainObjExitMonitor(vm);
     if (rc < 0)
@@ -1408,7 +1411,7 @@ qemuMigrationCapsCheck(virQEMUDriver *driver,
 
     priv->migrationCaps = virBitmapNew(QEMU_MIGRATION_CAP_LAST);
 
-    for (capStr = caps; *capStr; capStr++) {
+    for (i = 0, capStr = caps; *capStr; capStr++, i++) {
         int cap = qemuMigrationCapabilityTypeFromString(*capStr);
 
         if (cap < 0) {
@@ -1416,10 +1419,20 @@ qemuMigrationCapsCheck(virQEMUDriver *driver,
         } else {
             ignore_value(virBitmapSetBit(priv->migrationCaps, cap));
             VIR_DEBUG("Found migration capability: '%s'", *capStr);
+
+            if (virBitmapIsBitSet(capState, i))
+                ignore_value(virBitmapSetBit(enabled, cap));
         }
     }
 
-    if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATION_EVENT)) {
+    if (virBitmapIsBitSet(enabled, QEMU_MIGRATION_CAP_EVENTS)) {
+        if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATION_EVENT)) {
+            VIR_DEBUG("Migration events already enabled");
+        } else {
+            VIR_DEBUG("Migration events enabled; setting capability");
+            virQEMUCapsSet(priv->qemuCaps, QEMU_CAPS_MIGRATION_EVENT);
+        }
+    } else if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATION_EVENT)) {
         migEvent = virBitmapNew(QEMU_MIGRATION_CAP_LAST);
 
         ignore_value(virBitmapSetBit(migEvent, QEMU_MIGRATION_CAP_EVENTS));
-- 
2.35.1