fix: fp8 quantization failure of qwen 2.5 VL 7B model (#10112)

Signed-off-by: PanJason <pyyjason@gmail.com>

python/sglang/srt/layers/linear.py

@@ -31,6 +31,7 @@ from sglang.srt.layers.parameter import (
     _ColumnvLLMParameter,
 )
 from sglang.srt.layers.quantization.unquant import UnquantizedLinearMethod
+from sglang.srt.layers.utils import pad_or_narrow_weight
 from sglang.srt.utils import is_cpu, is_npu, set_weight_attrs
 
 if TYPE_CHECKING:
@@ -625,9 +626,16 @@ class MergedColumnParallelLinear(ColumnParallelLinear):
                 # bitsandbytes loads the weights of the specific portion
                 # no need to narrow here
                 if not use_bitsandbytes_4bit and not self.use_presharded_weights:
-                    loaded_weight = loaded_weight.narrow(
-                        output_dim, start_idx, shard_size
-                    )
+                    # Padding for special case like qwen2_5_VL's mlp which is not 8-aligned
+                    end_idx = start_idx + shard_size
+                    if end_idx > loaded_weight.shape[output_dim]:
+                        loaded_weight = pad_or_narrow_weight(
+                            loaded_weight, output_dim, start_idx, shard_size
+                        )
+                    else:
+                        loaded_weight = loaded_weight.narrow(
+                            output_dim, start_idx, shard_size
+                        )
 
         # Special case for AQLM codebooks.
         elif is_metadata:
@@ -1302,7 +1310,16 @@ class RowParallelLinear(LinearBase):
                     shard_size,
                 )
             else:
-                loaded_weight = loaded_weight.narrow(input_dim, start_idx, shard_size)
+                # Padding for special case like qwen2_5_VL's mlp which is not 8-aligned
+                end_idx = start_idx + shard_size
+                if end_idx > loaded_weight.shape[input_dim]:
+                    loaded_weight = pad_or_narrow_weight(
+                        loaded_weight, input_dim, start_idx, shard_size
+                    )
+                else:
+                    loaded_weight = loaded_weight.narrow(
+                        input_dim, start_idx, shard_size
+                    )
 
         # Special case for loading scales off disk, which often do not
         # have a shape (such as in the case of AutoFP8).