diff --git a/serve/mlc_serve/engine/staging_engine_worker.py b/serve/mlc_serve/engine/staging_engine_worker.py
index 347d678745..02c4e8d5ab 100644
--- a/serve/mlc_serve/engine/staging_engine_worker.py
+++ b/serve/mlc_serve/engine/staging_engine_worker.py
@@ -128,6 +128,33 @@ def cancel_request(self, request_id: RequestId):
     def stop_request(self, request_id: RequestId):
         self._cacnel_or_stop_request(request_id, self.stopped_requests)
 
+    def create_aborted_outputs(
+        self,
+        cancelled_or_stopped_requests: List[RequestState],
+        finish_reason: FinishReason,
+    ):
+        outputs = []
+        for state in cancelled_or_stopped_requests:
+            err = None
+            if state.validation_err:
+                err = state.validation_err
+
+            for gen_seq in state.generation_sequences:
+                outputs.append(
+                    SequenceGenerationOutput(
+                        id=gen_seq.seq_id,
+                        new_tokens=[],
+                        finish_reason=finish_reason,
+                        error=err,
+                    )
+                )
+
+            if state.request_id in self.current_batch:
+                self.remove_request_from_batch(state.request_id)
+
+        cancelled_or_stopped_requests.clear()
+        return outputs
+
     def wait_for_request(self, timeout_seconds=None):
         with self.queue_lock:
             self.has_new_requests.wait_for(
@@ -166,45 +193,24 @@ def step(self) -> GenerationLoopWorkerOutput:
                 duration = time.time() - state.arrival_timestamp
                 self.prom_metrics.histogram(E2E_LATENCY).observe(duration)
 
-        for state in self.stopped_requests:
-            for gen_seq in state.generation_sequences:
-                outputs.append(
-                    SequenceGenerationOutput(
-                        id=gen_seq.seq_id,
-                        new_tokens=[],
-                        finish_reason=FinishReason.Stop,
-                    )
-                )
-
-            if state.request_id in self.current_batch:
-                self.remove_request_from_batch(state.request_id)
-
-        self.stopped_requests.clear()
+        outputs += self.create_aborted_outputs(
+            self.stopped_requests, finish_reason=FinishReason.Stop
+        )
 
         with self.queue_lock:
             # Hold the lock here since self.cancelled_requests is modified in add(...) as well.
-            for state in self.cancelled_requests:
-                err = None
-                if state.validation_err:
-                    err = state.validation_err
-
-                for gen_seq in state.generation_sequences:
-                    outputs.append(
-                        SequenceGenerationOutput(
-                            id=gen_seq.seq_id,
-                            new_tokens=[],
-                            finish_reason=FinishReason.Cancelled,
-                            error=err,
-                        )
-                    )
-
-                if state.request_id in self.current_batch:
-                    self.remove_request_from_batch(state.request_id)
-
-            self.cancelled_requests.clear()
+            outputs += self.create_aborted_outputs(
+                self.cancelled_requests, finish_reason=FinishReason.Cancelled
+            )
 
         self._adjust_batch()
 
+        with self.queue_lock:
+            # _adjust_batch also adds to self.cancelled_requests
+            outputs += self.create_aborted_outputs(
+                self.cancelled_requests, finish_reason=FinishReason.Cancelled
+            )
+
         if not self.current_batch:
             if len(self.queue) > 0:
                 LOG.warn(
@@ -223,10 +229,9 @@ def step(self) -> GenerationLoopWorkerOutput:
         for res in results:
             request_id = res.sequence_id.request_id
 
-            if res.error is not None:
-                if request_id not in failed_requests:
-                    failed_requests.add(request_id)
-                    self.remove_request_from_batch(request_id)
+            if res.error is not None and request_id not in failed_requests:
+                failed_requests.add(request_id)
+                self.remove_request_from_batch(request_id)
 
                 outputs.append(
                     SequenceGenerationOutput(
@@ -275,7 +280,11 @@ def step(self) -> GenerationLoopWorkerOutput:
 
     def _adjust_batch(self):
         with self.queue_lock:
-            num_eviction = self.evict_request()
+            num_eviction = self.evict_request(
+                cancell_callback=lambda request_id: self.cancelled_requests.append(
+                    self.current_batch[request_id]
+                )
+            )
             self.prom_metrics.counter(NUM_CACHE_EVICTONS).inc(num_eviction)
 
             if self.cache_manager.get_max_new_tokens() <= self.max_decode_steps: