[Bugfix] Fix HunyuanOCR cross-image contamination in batch processing (#30344)

Signed-off-by: Lennart Brog <lennart.borg@list-ag.de>
Signed-off-by: Anker <20343812+anker-c2@users.noreply.github.com>

vllm/model_executor/models/hunyuan_vision.py

@@ -502,6 +502,7 @@ class HunYuanVisionTransformer(nn.Module):
         cu_seqlens: list = [0]
 
         hidden_states = x.to(device=self.device, dtype=self.dtype)
+        # embeddings = patch_embeds + patch_pos_embed
         hidden_states = self.embeddings(hidden_states, grid_thw)
 
         for t, h, w in grid_thw:
@@ -515,8 +516,14 @@ class HunYuanVisionTransformer(nn.Module):
 
         hidden_states = hidden_states.reshape(seq_len, -1)
         hidden_states = hidden_states.unsqueeze(0)
-        for layer_num, layer in enumerate(self.layers):
-            hidden_states = layer(hidden_states)
+
+        # build per-image lengths once
+        split_lengths = [int(h) * int(w) for (_, h, w) in grid_thw]
+        for layer in self.layers:
+            # hidden_states: (1, T_total, D)
+            parts = hidden_states.split(split_lengths, dim=1)  # list of (1, L_i, D)
+            parts = [layer(p) for p in parts]
+            hidden_states = torch.cat(parts, dim=1)
 
         # adapter
         split_lengths = (cu_seqlens[1:] - cu_seqlens[:-1]).tolist()