migration: Respect exit-on-error when migration fails before resuming

When exit-on-error was added to migration, it wasn't added to postcopy.
Even though postcopy migration will usually pause and not fail, in cases
it does unrecoverably fail before destination side has been started,
exit-on-error will allow management to query the error.

Signed-off-by: Juraj Marcin <jmarcin@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20251103183301.3840862-7-jmarcin@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>

diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index 48cbb46c278b73cddd93635f4bb19bc0a5073f78..91431f02a4c078d254af02c2caa8ea30d4b8004a 100644 (file)
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -2080,11 +2080,16 @@ bool postcopy_is_paused(MigrationStatus status)
 
 static void postcopy_listen_thread_bh(void *opaque)
 {
+    MigrationState *s = migrate_get_current();
     MigrationIncomingState *mis = migration_incoming_get_current();
 
     migration_incoming_state_destroy();
 
-    if (mis->state == MIGRATION_STATUS_FAILED) {
+    if (mis->state == MIGRATION_STATUS_FAILED && mis->exit_on_error) {
+        WITH_QEMU_LOCK_GUARD(&s->error_mutex) {
+            error_report_err(s->error);
+            s->error = NULL;
+        }
         /*
          * If something went wrong then we have a bad state so exit;
          * we only could have gotten here if something failed before