[diffusion] fix: fix Z-Image Cache-DiT sequence-parallel override (#25305)

python/sglang/multimodal_gen/runtime/models/dits/zimage.py

@@ -256,6 +256,7 @@ class ZImageAttention(nn.Module):
         freqs_cis: Optional[Tuple[torch.Tensor, torch.Tensor]] = None,
         num_replicated_prefix: int = 0,
         num_replicated_suffix: int = 0,
+        skip_sequence_parallel_override: bool = False,
     ):
         if self.use_fused_qkv:
             qkv, _ = self.to_qkv(hidden_states)
@@ -360,6 +361,7 @@ class ZImageAttention(nn.Module):
                 v,
                 num_replicated_prefix=num_replicated_prefix,
                 num_replicated_suffix=num_replicated_suffix,
+                skip_sequence_parallel_override=skip_sequence_parallel_override,
             )
         hidden_states = hidden_states.flatten(2)
 
@@ -452,6 +454,7 @@ class ZImageTransformerBlock(nn.Module):
         adaln_input: Optional[torch.Tensor] = None,
         num_replicated_prefix: int = 0,
         num_replicated_suffix: int = 0,
+        skip_sequence_parallel_override: bool = False,
     ):
         if self.modulation:
             assert adaln_input is not None
@@ -467,6 +470,7 @@ class ZImageTransformerBlock(nn.Module):
                 freqs_cis=freqs_cis,
                 num_replicated_prefix=num_replicated_prefix,
                 num_replicated_suffix=num_replicated_suffix,
+                skip_sequence_parallel_override=skip_sequence_parallel_override,
             )
             if (
                 _is_cuda
@@ -509,6 +513,7 @@ class ZImageTransformerBlock(nn.Module):
                 freqs_cis=freqs_cis,
                 num_replicated_prefix=num_replicated_prefix,
                 num_replicated_suffix=num_replicated_suffix,
+                skip_sequence_parallel_override=skip_sequence_parallel_override,
             )
             x = x + self.attention_norm2(attn_out)
 
@@ -1002,13 +1007,13 @@ class ZImageTransformer2DModel(CachableDiT, OffloadableDiTMixin):
         )
         num_replicated_suffix = cap_seq_len if not use_full_unified_sequence else 0
 
-        for layer_id, layer in enumerate(self.layers):
+        for layer in self.layers:
-            layer.attention.attn.skip_sequence_parallel = use_full_unified_sequence
             unified = layer(
                 unified,
                 unified_freqs_cis,
                 adaln_input,
                 num_replicated_suffix=num_replicated_suffix,
+                skip_sequence_parallel_override=use_full_unified_sequence,
             )
 
         unified = self.all_final_layer[f"{patch_size}-{f_patch_size}"](