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-rw-r--r--migration/ram.c22
1 files changed, 15 insertions, 7 deletions
diff --git a/migration/ram.c b/migration/ram.c
index d26dbd37c4..fd8d83b63c 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -831,14 +831,22 @@ static inline bool migration_bitmap_clear_dirty(RAMState *rs,
     bool ret;
 
     /*
-     * Clear dirty bitmap if needed.  This _must_ be called before we
-     * send any of the page in the chunk because we need to make sure
-     * we can capture further page content changes when we sync dirty
-     * log the next time.  So as long as we are going to send any of
-     * the page in the chunk we clear the remote dirty bitmap for all.
-     * Clearing it earlier won't be a problem, but too late will.
+     * During the last stage (after source VM stopped), resetting the write
+     * protections isn't needed as we know there will be either (1) no
+     * further writes if migration will complete, or (2) migration fails
+     * at last then tracking isn't needed either.
      */
-    migration_clear_memory_region_dirty_bitmap(rb, page);
+    if (!rs->last_stage) {
+        /*
+         * Clear dirty bitmap if needed.  This _must_ be called before we
+         * send any of the page in the chunk because we need to make sure
+         * we can capture further page content changes when we sync dirty
+         * log the next time.  So as long as we are going to send any of
+         * the page in the chunk we clear the remote dirty bitmap for all.
+         * Clearing it earlier won't be a problem, but too late will.
+         */
+        migration_clear_memory_region_dirty_bitmap(rb, page);
+    }
 
     ret = test_and_clear_bit(page, rb->bmap);
     if (ret) {