Re: [PATCH v4 14/25] memory: Add Error** argument to the global_dirty_log routines

[Cédric Le Goater]

--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2836,18 +2836,31 @@ static void 
migration_bitmap_clear_discarded_pages(RAMState *rs)

static void ram_init_bitmaps(RAMState *rs)

  {
+    Error *local_err = NULL;
+    bool ret = true;
+
      qemu_mutex_lock_ramlist();

WITH_RCU_READ_LOCK_GUARD() {

          ram_list_init_bitmaps();
          /* We don't use dirty log with background snapshots */
          if (!migrate_background_snapshot()) {
-            memory_global_dirty_log_start(GLOBAL_DIRTY_MIGRATION);
+            ret = memory_global_dirty_log_start(GLOBAL_DIRTY_MIGRATION,
+                                                &local_err);
+            if (!ret) {
+                error_report_err(local_err);
+                goto out_unlock;

Here we may need to free the bitmaps created in ram_list_init_bitmaps().

We can have a helper ram_bitmaps_destroy() for that.

One thing be careful is the new file_bmap can be created but missing in the
ram_save_cleanup(), it's because it's freed earlier.  IMHO if we will have
a new ram_bitmaps_destroy() we can unconditionally free file_bmap there
too, as if it's freed early g_free() is noop.

OK. Let's do that in a new prereq patch. I will change ram_state_init()
and xbzrle_init() to take an Error ** argument while at it.


Thanks,

C.