Make migration_connect_set_error() take ownership of the error always.
Paving way for making migrate_set_error() to take ownership.

When at it, renaming it to migration_connect_error_propagate(), following
Error API, to imply the Error object ownership transition.

NOTE: this patch also makes migration_connect() to take ownership of the
Error passed in.

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Link: https://lore.kernel.org/r/20251201194510.1121221-5-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 migration/channel.c   | 1 -
 migration/migration.c | 9 +++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/migration/channel.c b/migration/channel.c
index 462cc183e1..92435fa7f7 100644
--- a/migration/channel.c
+++ b/migration/channel.c
@@ -95,7 +95,6 @@ void migration_channel_connect(MigrationState *s,
         }
     }
     migration_connect(s, error);
-    error_free(error);
 }
 
 
diff --git a/migration/migration.c b/migration/migration.c
index b316ee01ab..0ff8b31a88 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1575,7 +1575,7 @@ static void migrate_error_free(MigrationState *s)
     }
 }
 
-static void migration_connect_set_error(MigrationState *s, const Error *error)
+static void migration_connect_error_propagate(MigrationState *s, Error *error)
 {
     MigrationStatus current = s->state;
     MigrationStatus next;
@@ -1602,6 +1602,7 @@ static void migration_connect_set_error(MigrationState *s, const Error *error)
 
     migrate_set_state(&s->state, current, next);
     migrate_set_error(s, error);
+    error_free(error);
 }
 
 void migration_cancel(void)
@@ -2292,7 +2293,7 @@ void qmp_migrate(const char *uri, bool has_channels,
 
 out:
     if (local_err) {
-        migration_connect_set_error(s, local_err);
+        migration_connect_error_propagate(s, error_copy(local_err));
         error_propagate(errp, local_err);
     }
 }
@@ -2337,7 +2338,7 @@ static void qmp_migrate_finish(MigrationAddress *addr, bool resume_requested,
         if (!resume_requested) {
             yank_unregister_instance(MIGRATION_YANK_INSTANCE);
         }
-        migration_connect_set_error(s, local_err);
+        migration_connect_error_propagate(s, error_copy(local_err));
         error_propagate(errp, local_err);
         return;
     }
@@ -4039,7 +4040,7 @@ void migration_connect(MigrationState *s, Error *error_in)
 
     s->expected_downtime = migrate_downtime_limit();
     if (error_in) {
-        migration_connect_set_error(s, error_in);
+        migration_connect_error_propagate(s, error_in);
         if (resume) {
             /*
              * Don't do cleanup for resume if channel is invalid, but only dump
-- 
2.50.1