diff --git a/migration/ram.c b/migration/ram.c
index 01315edd66..0747873ca9 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -342,7 +342,7 @@ struct RAMState {
     uint64_t target_page_count;
     /* number of dirty bits in the bitmap */
     uint64_t migration_dirty_pages;
-    /* protects modification of the bitmap */
+    /* Protects modification of the bitmap and migration dirty pages */
     QemuMutex bitmap_mutex;
     /* The RAMBlock used in the last src_page_requests */
     RAMBlock *last_req_rb;
@@ -1590,11 +1590,14 @@ static inline bool migration_bitmap_clear_dirty(RAMState *rs,
 {
     bool ret;
 
+    qemu_mutex_lock(&rs->bitmap_mutex);
     ret = test_and_clear_bit(page, rb->bmap);
 
     if (ret) {
         rs->migration_dirty_pages--;
     }
+    qemu_mutex_unlock(&rs->bitmap_mutex);
+
     return ret;
 }