diff --git a/vllm/nvfp4_cutedsl.py b/vllm/nvfp4_cutedsl.py
index a57dc111..0a46718c 100644
--- a/vllm/nvfp4_cutedsl.py
+++ b/vllm/nvfp4_cutedsl.py
@@ -119,14 +119,24 @@ class CuTeDSLMoERunner:
             for _ in range(self.num_experts)
         ]
         
-        # Padded x_sf buffers: num_experts * max_chunks * 128 rows (fixed layout)
+        # Padded x_sf buffers: SHARED across all runners (not per-layer)
+        # Same reasoning as padded_hidden/activated — layers run sequentially.
         max_sf_rows = self.num_experts * self._max_chunks_per_expert * 128
-        self._padded_x_sf_buf_l1 = torch.zeros(
-            max_sf_rows, padded_cols_l1, dtype=torch.float16, device=self.device
-        ).to(torch.float8_e4m3fn)
-        self._padded_x_sf_buf_l2 = torch.zeros(
-            max_sf_rows, padded_cols_l2, dtype=torch.float16, device=self.device
-        ).to(torch.float8_e4m3fn)
+        if 'xsf_l1' not in CuTeDSLMoERunner._shared_padded_bufs[device_key]:
+            CuTeDSLMoERunner._shared_padded_bufs[device_key].update({
+                'xsf_l1': torch.zeros(
+                    max_sf_rows, padded_cols_l1, dtype=torch.float16, device=self.device
+                ).to(torch.float8_e4m3fn),
+                'xsf_l2': torch.zeros(
+                    max_sf_rows, padded_cols_l2, dtype=torch.float16, device=self.device
+                ).to(torch.float8_e4m3fn),
+                'output': torch.zeros(
+                    self.max_num_tokens, self.hidden_size, dtype=torch.bfloat16, device=self.device
+                ),
+            })
+        self._padded_x_sf_buf_l1 = CuTeDSLMoERunner._shared_padded_bufs[device_key]['xsf_l1']
+        self._padded_x_sf_buf_l2 = CuTeDSLMoERunner._shared_padded_bufs[device_key]['xsf_l2']
+        self._output_buf = CuTeDSLMoERunner._shared_padded_bufs[device_key]['output']
         
         # Pre-allocated global_scale_a buffers (filled via .fill_(), no torch.full during capture)
         self._l1_gsa_buf = torch.zeros(self.num_experts, dtype=torch.float32, device=self.device)