[Qemu-devel] [PATCH] migration: fix detached migration with fd

[Juan Quintela]

Migration with fd uses s->mon to pass the fd.  But we only assign the
s->mon for !detached migration.  Fix it.  Once there add a comment
indicating that s->mon has two uses.

Bug reported by:  Wen Congyang <address@hidden>

Signed-off-by: Juan Quintela <address@hidden>
CC:  Wen Congyang <address@hidden>
---
 migration.c |   12 ++++++++++--
 1 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/migration.c b/migration.c
index 4b17566..41c3c24 100644
--- a/migration.c
+++ b/migration.c
@@ -155,7 +155,6 @@ MigrationInfo *qmp_query_migrate(Error **errp)

 static void migrate_fd_monitor_suspend(MigrationState *s, Monitor *mon)
 {
-    s->mon = mon;
     if (monitor_suspend(mon) == 0) {
         DPRINTF("suspending monitor\n");
     } else {
@@ -383,7 +382,12 @@ static MigrationState *migrate_init(Monitor *mon, int 
detach, int blk, int inc)
     s->bandwidth_limit = bandwidth_limit;
     s->blk = blk;
     s->shared = inc;
-    s->mon = NULL;
+
+    /* s->mon is used for two things:
+       - pass fd in fd migration
+       - suspend/resume monitor for not detached migration
+    */
+    s->mon = mon;
     s->bandwidth_limit = bandwidth_limit;
     s->state = MIG_STATE_SETUP;

@@ -435,6 +439,10 @@ int do_migrate(Monitor *mon, const QDict *qdict, QObject 
**ret_data)
         return ret;
     }

+    if (detach) {
+        s->mon = NULL;
+    }
+
     notifier_list_notify(&migration_state_notifiers, s);
     return 0;
 }
-- 
1.7.7