diff --git a/include/migration/migration.h b/include/migration/migration.h
index b9b706a7e3..71ce19062c 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -285,6 +285,7 @@ int ram_postcopy_send_discard_bitmap(MigrationState *ms);
 int ram_discard_range(MigrationIncomingState *mis, const char *block_name,
                       uint64_t start, size_t length);
 int ram_postcopy_incoming_init(MigrationIncomingState *mis);
+void ram_postcopy_migrated_memory_release(MigrationState *ms);
 
 /**
  * @migrate_add_blocker - prevent migration from proceeding
diff --git a/migration/migration.c b/migration/migration.c
index 68afc07016..2a26a20aaf 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1722,6 +1722,10 @@ static int postcopy_start(MigrationState *ms, bool *old_vm_running)
      */
     qemu_savevm_send_ping(ms->to_dst_file, 4);
 
+    if (migrate_release_ram()) {
+        ram_postcopy_migrated_memory_release(ms);
+    }
+
     ret = qemu_file_get_error(ms->to_dst_file);
     if (ret) {
         error_report("postcopy_start: Migration stream errored");
diff --git a/migration/ram.c b/migration/ram.c
index c22209db30..67f2efbc59 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1537,6 +1537,25 @@ void ram_debug_dump_bitmap(unsigned long *todump, bool expected)
 
 /* **** functions for postcopy ***** */
 
+void ram_postcopy_migrated_memory_release(MigrationState *ms)
+{
+    struct RAMBlock *block;
+    unsigned long *bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
+
+    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+        unsigned long first = block->offset >> TARGET_PAGE_BITS;
+        unsigned long range = first + (block->used_length >> TARGET_PAGE_BITS);
+        unsigned long run_start = find_next_zero_bit(bitmap, range, first);
+
+        while (run_start < range) {
+            unsigned long run_end = find_next_bit(bitmap, range, run_start + 1);
+            ram_discard_range(NULL, block->idstr, run_start << TARGET_PAGE_BITS,
+                              (run_end - run_start) << TARGET_PAGE_BITS);
+            run_start = find_next_zero_bit(bitmap, range, run_end + 1);
+        }
+    }
+}
+
 /*
  * Callback from postcopy_each_ram_send_discard for each RAMBlock
  * Note: At this point the 'unsentmap' is the processed bitmap combined