fix?

src/axolotl/kernels/moe/torch_grouped.py

@@ -57,8 +57,8 @@ def _stack_weights(
 def _call_grouped_mm(
     As: List[torch.Tensor], Bs: List[torch.Tensor], dtype: torch.dtype
 ) -> Optional[List[torch.Tensor]]:
-    if not As:
+    if not As or dtype not in (torch.bfloat16, torch.float16):
-        return []
+        return [] if not As else None
 
     try:
         As2 = [a.to(dtype).contiguous().view(a.shape[0], a.shape[1]) for a in As]
@@ -94,6 +94,14 @@ def moe_ffn_forward_grouped(
 
     routing_dtype = gate_linear.weight.dtype
 
+    expert_dtype = hidden_states.dtype
+    if expert_dtype not in (torch.bfloat16, torch.float16):
+        _LOGGER.debug(
+            "torch_grouped: unsupported expert dtype %s; falling back to naive",
+            expert_dtype,
+        )
+        return None, None
+
     sample_mod = getattr(
         experts_module[0], "mlp", getattr(experts_module[0], "ffn", experts_module[0])
     )
@@ -102,7 +110,6 @@ def moe_ffn_forward_grouped(
         and hasattr(sample_mod, "w3")
         and hasattr(sample_mod, "w2")
     ):
-        expert_dtype = sample_mod.w1.weight.dtype
         w13 = _stack_weights(
             experts_module, ("w1", "w3"), key="w13", dtype=expert_dtype, device=device
         )
@@ -111,10 +118,8 @@ def moe_ffn_forward_grouped(
         )
     else:
         if hasattr(sample_mod, "gate_up_proj"):
-            expert_dtype = sample_mod.gate_up_proj.weight.dtype
             names13: Tuple[str, ...] = ("gate_up_proj",)
         else:
-            expert_dtype = sample_mod.up_proj.weight.dtype
             names13 = ("up_proj", "gate_proj")
         w13 = _stack_weights(
             experts_module, names13, key="w13", dtype=expert_dtype, device=device