diff --git a/src/Processors/Executors/PushingAsyncPipelineExecutor.cpp b/src/Processors/Executors/PushingAsyncPipelineExecutor.cpp
index 08ff6d4d96c4..c2b687192026 100644
--- a/src/Processors/Executors/PushingAsyncPipelineExecutor.cpp
+++ b/src/Processors/Executors/PushingAsyncPipelineExecutor.cpp
@@ -41,6 +41,7 @@ class PushingAsyncSource : public ISource
 
     void finish()
     {
+        std::unique_lock lock(mutex);
         is_finished = true;
         condvar.notify_all();
     }
@@ -64,7 +65,7 @@ class PushingAsyncSource : public ISource
 private:
     Chunk data;
     bool has_data = false;
-    std::atomic_bool is_finished = false;
+    bool is_finished = false;
     std::mutex mutex;
     std::condition_variable condvar;
 };