update

Improve docstring scheduling ipndm

.github/workflows/benchmark.yml

@@ -62,20 +62,6 @@ jobs:
         with:
           name: benchmark_test_reports
           path: benchmarks/${{ env.BASE_PATH }}
-      
-      # TODO: enable this once the connection problem has been resolved.
-      - name: Update benchmarking results to DB
-        env:
-          PGDATABASE: metrics
-          PGHOST: ${{ secrets.DIFFUSERS_BENCHMARKS_PGHOST }}
-          PGUSER: transformers_benchmarks
-          PGPASSWORD: ${{ secrets.DIFFUSERS_BENCHMARKS_PGPASSWORD }}
-          BRANCH_NAME: ${{ github.head_ref || github.ref_name }}
-        run: |
-          git config --global --add safe.directory /__w/diffusers/diffusers
-          commit_id=$GITHUB_SHA
-          commit_msg=$(git show -s --format=%s "$commit_id" | cut -c1-70)
-          cd benchmarks && python populate_into_db.py "$BRANCH_NAME" "$commit_id" "$commit_msg"
 
       - name: Report success status
         if: ${{ success() }}

.github/workflows/pypi_publish.yaml

@@ -54,7 +54,6 @@ jobs:
           python -m pip install --upgrade pip
           pip install -U setuptools wheel twine
           pip install -U torch --index-url https://download.pytorch.org/whl/cpu
-          pip install -U transformers
 
       - name: Build the dist files
         run: python setup.py bdist_wheel && python setup.py sdist
@@ -69,6 +68,8 @@ jobs:
         run: |
           pip install diffusers && pip uninstall diffusers -y
           pip install -i https://test.pypi.org/simple/ diffusers
+          pip install -U transformers
+          python utils/print_env.py
           python -c "from diffusers import __version__; print(__version__)"
           python -c "from diffusers import DiffusionPipeline; pipe = DiffusionPipeline.from_pretrained('fusing/unet-ldm-dummy-update'); pipe()"
           python -c "from diffusers import DiffusionPipeline; pipe = DiffusionPipeline.from_pretrained('hf-internal-testing/tiny-stable-diffusion-pipe', safety_checker=None); pipe('ah suh du')"

benchmarks/populate_into_db.py

@@ -1,166 +0,0 @@
-import argparse
-import os
-import sys
-
-import gpustat
-import pandas as pd
-import psycopg2
-import psycopg2.extras
-from psycopg2.extensions import register_adapter
-from psycopg2.extras import Json
-
-
-register_adapter(dict, Json)
-
-FINAL_CSV_FILENAME = "collated_results.csv"
-# https://github.com/huggingface/transformers/blob/593e29c5e2a9b17baec010e8dc7c1431fed6e841/benchmark/init_db.sql#L27
-BENCHMARKS_TABLE_NAME = "benchmarks"
-MEASUREMENTS_TABLE_NAME = "model_measurements"
-
-
-def _init_benchmark(conn, branch, commit_id, commit_msg):
-    gpu_stats = gpustat.GPUStatCollection.new_query()
-    metadata = {"gpu_name": gpu_stats[0]["name"]}
-    repository = "huggingface/diffusers"
-    with conn.cursor() as cur:
-        cur.execute(
-            f"INSERT INTO {BENCHMARKS_TABLE_NAME} (repository, branch, commit_id, commit_message, metadata) VALUES (%s, %s, %s, %s, %s) RETURNING benchmark_id",
-            (repository, branch, commit_id, commit_msg, metadata),
-        )
-        benchmark_id = cur.fetchone()[0]
-        print(f"Initialised benchmark #{benchmark_id}")
-        return benchmark_id
-
-
-def parse_args():
-    parser = argparse.ArgumentParser()
-    parser.add_argument(
-        "branch",
-        type=str,
-        help="The branch name on which the benchmarking is performed.",
-    )
-
-    parser.add_argument(
-        "commit_id",
-        type=str,
-        help="The commit hash on which the benchmarking is performed.",
-    )
-
-    parser.add_argument(
-        "commit_msg",
-        type=str,
-        help="The commit message associated with the commit, truncated to 70 characters.",
-    )
-    args = parser.parse_args()
-    return args
-
-
-if __name__ == "__main__":
-    args = parse_args()
-    try:
-        conn = psycopg2.connect(
-            host=os.getenv("PGHOST"),
-            database=os.getenv("PGDATABASE"),
-            user=os.getenv("PGUSER"),
-            password=os.getenv("PGPASSWORD"),
-        )
-        print("DB connection established successfully.")
-    except Exception as e:
-        print(f"Problem during DB init: {e}")
-        sys.exit(1)
-
-    try:
-        benchmark_id = _init_benchmark(
-            conn=conn,
-            branch=args.branch,
-            commit_id=args.commit_id,
-            commit_msg=args.commit_msg,
-        )
-    except Exception as e:
-        print(f"Problem during initializing benchmark: {e}")
-        sys.exit(1)
-
-    cur = conn.cursor()
-
-    df = pd.read_csv(FINAL_CSV_FILENAME)
-
-    # Helper to cast values (or None) given a dtype
-    def _cast_value(val, dtype: str):
-        if pd.isna(val):
-            return None
-
-        if dtype == "text":
-            return str(val).strip()
-
-        if dtype == "float":
-            try:
-                return float(val)
-            except ValueError:
-                return None
-
-        if dtype == "bool":
-            s = str(val).strip().lower()
-            if s in ("true", "t", "yes", "1"):
-                return True
-            if s in ("false", "f", "no", "0"):
-                return False
-            if val in (1, 1.0):
-                return True
-            if val in (0, 0.0):
-                return False
-            return None
-
-        return val
-
-    try:
-        rows_to_insert = []
-        for _, row in df.iterrows():
-            scenario = _cast_value(row.get("scenario"), "text")
-            model_cls = _cast_value(row.get("model_cls"), "text")
-            num_params_B = _cast_value(row.get("num_params_B"), "float")
-            flops_G = _cast_value(row.get("flops_G"), "float")
-            time_plain_s = _cast_value(row.get("time_plain_s"), "float")
-            mem_plain_GB = _cast_value(row.get("mem_plain_GB"), "float")
-            time_compile_s = _cast_value(row.get("time_compile_s"), "float")
-            mem_compile_GB = _cast_value(row.get("mem_compile_GB"), "float")
-            fullgraph = _cast_value(row.get("fullgraph"), "bool")
-            mode = _cast_value(row.get("mode"), "text")
-
-            # If "github_sha" column exists in the CSV, cast it; else default to None
-            if "github_sha" in df.columns:
-                github_sha = _cast_value(row.get("github_sha"), "text")
-            else:
-                github_sha = None
-
-            measurements = {
-                "scenario": scenario,
-                "model_cls": model_cls,
-                "num_params_B": num_params_B,
-                "flops_G": flops_G,
-                "time_plain_s": time_plain_s,
-                "mem_plain_GB": mem_plain_GB,
-                "time_compile_s": time_compile_s,
-                "mem_compile_GB": mem_compile_GB,
-                "fullgraph": fullgraph,
-                "mode": mode,
-                "github_sha": github_sha,
-            }
-            rows_to_insert.append((benchmark_id, measurements))
-
-        # Batch-insert all rows
-        insert_sql = f"""
-        INSERT INTO {MEASUREMENTS_TABLE_NAME} (
-            benchmark_id,
-            measurements
-        )
-        VALUES (%s, %s);
-        """
-
-        psycopg2.extras.execute_batch(cur, insert_sql, rows_to_insert)
-        conn.commit()
-
-        cur.close()
-        conn.close()
-    except Exception as e:
-        print(f"Exception: {e}")
-        sys.exit(1)

docs/source/en/api/modular_diffusers/pipeline_blocks.md

@@ -14,4 +14,8 @@
 
 ## AutoPipelineBlocks
 
-[[autodoc]] diffusers.modular_pipelines.modular_pipeline.AutoPipelineBlocks
+[[autodoc]] diffusers.modular_pipelines.modular_pipeline.AutoPipelineBlocks
+
+## ConditionalPipelineBlocks
+
+[[autodoc]] diffusers.modular_pipelines.modular_pipeline.ConditionalPipelineBlocks

docs/source/en/api/pipelines/cosmos.md

@@ -46,6 +46,20 @@ output = pipe(
 output.save("output.png")
 ```
 
+## Cosmos2_5_TransferPipeline
+
+[[autodoc]] Cosmos2_5_TransferPipeline
+  - all
+  - __call__
+
+
+## Cosmos2_5_PredictBasePipeline
+
+[[autodoc]] Cosmos2_5_PredictBasePipeline
+  - all
+  - __call__
+
+
 ## CosmosTextToWorldPipeline
 
 [[autodoc]] CosmosTextToWorldPipeline
@@ -70,12 +84,6 @@ output.save("output.png")
   - all
   - __call__
 
-## Cosmos2_5_PredictBasePipeline
-
-[[autodoc]] Cosmos2_5_PredictBasePipeline
-  - all
-  - __call__
-
 ## CosmosPipelineOutput
 
 [[autodoc]] pipelines.cosmos.pipeline_output.CosmosPipelineOutput

docs/source/en/modular_diffusers/auto_pipeline_blocks.md

@@ -121,7 +121,7 @@ from diffusers.modular_pipelines import AutoPipelineBlocks
 
 class AutoImageBlocks(AutoPipelineBlocks):
     # List of sub-block classes to choose from
-    block_classes = [block_inpaint_cls, block_i2i_cls, block_t2i_cls]
+    block_classes = [InpaintBlock, ImageToImageBlock, TextToImageBlock]
     # Names for each block in the same order
     block_names = ["inpaint", "img2img", "text2img"]
     # Trigger inputs that determine which block to run
@@ -129,8 +129,8 @@ class AutoImageBlocks(AutoPipelineBlocks):
     # - "image" triggers img2img workflow (but only if mask is not provided)
     # - if none of above, runs the text2img workflow (default)
     block_trigger_inputs = ["mask", "image", None]
-    # Description is extremely important for AutoPipelineBlocks
 
+    @property
     def description(self):
         return (
             "Pipeline generates images given different types of conditions!\n"
@@ -141,7 +141,7 @@ class AutoImageBlocks(AutoPipelineBlocks):
         )
 ```
 
-It is **very** important to include a `description` to avoid any confusion over how to run a block and what inputs are required. While [`~modular_pipelines.AutoPipelineBlocks`] are convenient, it's conditional logic may be difficult to figure out if it isn't properly explained.
+It is **very** important to include a `description` to avoid any confusion over how to run a block and what inputs are required. While [`~modular_pipelines.AutoPipelineBlocks`] are convenient, its conditional logic may be difficult to figure out if it isn't properly explained.
 
 Create an instance of `AutoImageBlocks`.
 
@@ -152,5 +152,74 @@ auto_blocks = AutoImageBlocks()
 For more complex compositions, such as nested [`~modular_pipelines.AutoPipelineBlocks`] blocks when they're used as sub-blocks in larger pipelines, use the [`~modular_pipelines.SequentialPipelineBlocks.get_execution_blocks`] method to extract the a block that is actually run based on your input.
 
 ```py
-auto_blocks.get_execution_blocks("mask")
+auto_blocks.get_execution_blocks(mask=True)
+```
+
+## ConditionalPipelineBlocks
+
+[`~modular_pipelines.AutoPipelineBlocks`] is a special case of [`~modular_pipelines.ConditionalPipelineBlocks`]. While [`~modular_pipelines.AutoPipelineBlocks`] selects blocks based on whether a trigger input is provided or not, [`~modular_pipelines.ConditionalPipelineBlocks`] is able to select a block based on custom selection logic provided in the `select_block` method.
+
+Here is the same example written using [`~modular_pipelines.ConditionalPipelineBlocks`] directly:
+
+```py
+from diffusers.modular_pipelines import ConditionalPipelineBlocks
+
+class AutoImageBlocks(ConditionalPipelineBlocks):
+    block_classes = [InpaintBlock, ImageToImageBlock, TextToImageBlock]
+    block_names = ["inpaint", "img2img", "text2img"]
+    block_trigger_inputs = ["mask", "image"]
+    default_block_name = "text2img"
+
+    @property
+    def description(self):
+        return (
+            "Pipeline generates images given different types of conditions!\n"
+            + "This is an auto pipeline block that works for text2img, img2img and inpainting tasks.\n"
+            + " - inpaint workflow is run when `mask` is provided.\n"
+            + " - img2img workflow is run when `image` is provided (but only when `mask` is not provided).\n"
+            + " - text2img workflow is run when neither `image` nor `mask` is provided.\n"
+        )
+
+    def select_block(self, mask=None, image=None) -> str | None:
+        if mask is not None:
+            return "inpaint"
+        if image is not None:
+            return "img2img"
+        return None  # falls back to default_block_name ("text2img")
+```
+
+The inputs listed in `block_trigger_inputs` are passed as keyword arguments to `select_block()`. When `select_block` returns `None`, it falls back to `default_block_name`. If `default_block_name` is also `None`, the entire conditional block is skipped — this is useful for optional processing steps that should only run when specific inputs are provided.
+
+## Workflows
+
+Pipelines that contain conditional blocks ([`~modular_pipelines.AutoPipelineBlocks`] or [`~modular_pipelines.ConditionalPipelineBlocks]`) can support multiple workflows — for example, our SDXL modular pipeline supports a dozen workflows all in one pipeline. But this also means it can be confusing for users to know what workflows are supported and how to run them. For pipeline builders, it's useful to be able to extract only the blocks relevant to a specific workflow.
+
+We recommend defining a `_workflow_map` to give each workflow a name and explicitly list the inputs it requires.
+
+```py
+from diffusers.modular_pipelines import SequentialPipelineBlocks
+
+class MyPipelineBlocks(SequentialPipelineBlocks):
+    block_classes = [TextEncoderBlock, AutoImageBlocks, DecodeBlock]
+    block_names = ["text_encoder", "auto_image", "decode"]
+
+    _workflow_map = {
+        "text2image": {"prompt": True},
+        "image2image": {"image": True, "prompt": True},
+        "inpaint": {"mask": True, "image": True, "prompt": True},
+    }
+```
+
+All of our built-in modular pipelines come with pre-defined workflows. The `available_workflows` property lists all supported workflows:
+
+```py
+pipeline_blocks = MyPipelineBlocks()
+pipeline_blocks.available_workflows
+# ['text2image', 'image2image', 'inpaint']
+```
+
+Retrieve a specific workflow with `get_workflow` to inspect and debug a specific block that executes the workflow.
+
+```py
+pipeline_blocks.get_workflow("inpaint")
 ```

docs/source/en/training/distributed_inference.md

@@ -111,7 +111,7 @@ if __name__ == "__main__":
 Call `torchrun` to run the inference script and use the `--nproc_per_node` argument to set the number of GPUs to use.
 
 ```bash
-torchrun run_distributed.py --nproc_per_node=2
+torchrun --nproc_per_node=2 run_distributed.py
 ```
 
 ## device_map

docs/source/en/using-diffusers/automodel.md

@@ -97,5 +97,32 @@ If the custom model inherits from the [`ModelMixin`] class, it gets access to th
 > )
 > ```
 
+### Saving custom models
+
+Use [`~ConfigMixin.register_for_auto_class`] to add the `auto_map` entry to `config.json` automatically when saving. This avoids having to manually edit the config file.
+
+```py
+# my_model.py
+from diffusers import ModelMixin, ConfigMixin
+
+class MyCustomModel(ModelMixin, ConfigMixin):
+    ...
+
+MyCustomModel.register_for_auto_class("AutoModel")
+
+model = MyCustomModel(...)
+model.save_pretrained("./my_model")
+```
+
+The saved `config.json` will include the `auto_map` field.
+
+```json
+{
+  "auto_map": {
+    "AutoModel": "my_model.MyCustomModel"
+  }
+}
+```
+
 > [!NOTE]
 > Learn more about implementing custom models in the [Community components](../using-diffusers/custom_pipeline_overview#community-components) guide.

scripts/convert_cosmos_to_diffusers.py

@@ -94,9 +94,15 @@ python scripts/convert_cosmos_to_diffusers.py \
     --transformer_type Cosmos-2.5-Transfer-General-2B \
     --transformer_ckpt_path $transformer_ckpt_path \
     --vae_type wan2.1 \
-    --output_path converted/transfer/2b/general/depth \
+    --output_path converted/transfer/2b/general/depth/pipeline \
     --save_pipeline
 
+python scripts/convert_cosmos_to_diffusers.py \
+    --transformer_type Cosmos-2.5-Transfer-General-2B \
+    --transformer_ckpt_path $transformer_ckpt_path \
+    --vae_type wan2.1 \
+    --output_path converted/transfer/2b/general/depth/models
+
 # edge
 transformer_ckpt_path=~/.cache/huggingface/hub/models--nvidia--Cosmos-Transfer2.5-2B/snapshots/eb5325b77d358944da58a690157dd2b8071bbf85/general/edge/61f5694b-0ad5-4ecd-8ad7-c8545627d125_ema_bf16.pt
 
@@ -120,9 +126,15 @@ python scripts/convert_cosmos_to_diffusers.py \
     --transformer_type Cosmos-2.5-Transfer-General-2B \
     --transformer_ckpt_path $transformer_ckpt_path \
     --vae_type wan2.1 \
-    --output_path converted/transfer/2b/general/blur \
+    --output_path converted/transfer/2b/general/blur/pipeline \
     --save_pipeline
 
+python scripts/convert_cosmos_to_diffusers.py \
+    --transformer_type Cosmos-2.5-Transfer-General-2B \
+    --transformer_ckpt_path $transformer_ckpt_path \
+    --vae_type wan2.1 \
+    --output_path converted/transfer/2b/general/blur/models
+
 # seg
 transformer_ckpt_path=~/.cache/huggingface/hub/models--nvidia--Cosmos-Transfer2.5-2B/snapshots/eb5325b77d358944da58a690157dd2b8071bbf85/general/seg/5136ef49-6d8d-42e8-8abf-7dac722a304a_ema_bf16.pt
 
@@ -130,8 +142,14 @@ python scripts/convert_cosmos_to_diffusers.py \
     --transformer_type Cosmos-2.5-Transfer-General-2B \
     --transformer_ckpt_path $transformer_ckpt_path \
     --vae_type wan2.1 \
-    --output_path converted/transfer/2b/general/seg \
+    --output_path converted/transfer/2b/general/seg/pipeline \
     --save_pipeline
+
+python scripts/convert_cosmos_to_diffusers.py \
+    --transformer_type Cosmos-2.5-Transfer-General-2B \
+    --transformer_ckpt_path $transformer_ckpt_path \
+    --vae_type wan2.1 \
+    --output_path converted/transfer/2b/general/seg/models
 ```
 """
 

src/diffusers/configuration_utils.py

@@ -107,6 +107,38 @@ class ConfigMixin:
     has_compatibles = False
 
     _deprecated_kwargs = []
+    _auto_class = None
+
+    @classmethod
+    def register_for_auto_class(cls, auto_class="AutoModel"):
+        """
+        Register this class with the given auto class so that it can be loaded with `AutoModel.from_pretrained(...,
+        trust_remote_code=True)`.
+
+        When the config is saved, the resulting `config.json` will include an `auto_map` entry mapping the auto class
+        to this class's module and class name.
+
+        Args:
+            auto_class (`str` or type, *optional*, defaults to `"AutoModel"`):
+                The auto class to register this class with. Can be a string (e.g. `"AutoModel"`) or the class itself.
+                Currently only `"AutoModel"` is supported.
+
+        Example:
+
+        ```python
+        from diffusers import ModelMixin, ConfigMixin
+
+
+        class MyCustomModel(ModelMixin, ConfigMixin): ...
+
+
+        MyCustomModel.register_for_auto_class("AutoModel")
+        ```
+        """
+        if auto_class != "AutoModel":
+            raise ValueError(f"Only 'AutoModel' is supported, got '{auto_class}'.")
+
+        cls._auto_class = auto_class
 
     def register_to_config(self, **kwargs):
         if self.config_name is None:
@@ -621,6 +653,12 @@ class ConfigMixin:
         # pop the `_pre_quantization_dtype` as torch.dtypes are not serializable.
         _ = config_dict.pop("_pre_quantization_dtype", None)
 
+        if getattr(self, "_auto_class", None) is not None:
+            module = self.__class__.__module__.split(".")[-1]
+            auto_map = config_dict.get("auto_map", {})
+            auto_map[self._auto_class] = f"{module}.{self.__class__.__name__}"
+            config_dict["auto_map"] = auto_map
+
         return json.dumps(config_dict, indent=2, sort_keys=True) + "\n"
 
     def to_json_file(self, json_file_path: str | os.PathLike):

src/diffusers/loaders/lora_conversion_utils.py

@@ -856,7 +856,7 @@ def _convert_kohya_flux_lora_to_diffusers(state_dict):
                 )
             state_dict = {k: v for k, v in state_dict.items() if not k.startswith("text_encoders.t5xxl.transformer.")}
 
-        has_diffb = any("diff_b" in k and k.startswith(("lora_unet_", "lora_te_")) for k in state_dict)
+        has_diffb = any("diff_b" in k and k.startswith(("lora_unet_", "lora_te_", "lora_te1_")) for k in state_dict)
         if has_diffb:
             zero_status_diff_b = state_dict_all_zero(state_dict, ".diff_b")
             if zero_status_diff_b:
@@ -895,7 +895,7 @@ def _convert_kohya_flux_lora_to_diffusers(state_dict):
         state_dict = {
             _custom_replace(k, limit_substrings): v
             for k, v in state_dict.items()
-            if k.startswith(("lora_unet_", "lora_te_"))
+            if k.startswith(("lora_unet_", "lora_te_", "lora_te1_"))
         }
 
         if any("text_projection" in k for k in state_dict):

src/diffusers/models/attention_dispatch.py

@@ -62,6 +62,8 @@ _REQUIRED_FLEX_VERSION = "2.5.0"
 _REQUIRED_XLA_VERSION = "2.2"
 _REQUIRED_XFORMERS_VERSION = "0.0.29"
 
+logger = get_logger(__name__)  # pylint: disable=invalid-name
+
 _CAN_USE_FLASH_ATTN = is_flash_attn_available() and is_flash_attn_version(">=", _REQUIRED_FLASH_VERSION)
 _CAN_USE_FLASH_ATTN_3 = is_flash_attn_3_available()
 _CAN_USE_AITER_ATTN = is_aiter_available() and is_aiter_version(">=", _REQUIRED_AITER_VERSION)
@@ -73,8 +75,18 @@ _CAN_USE_XFORMERS_ATTN = is_xformers_available() and is_xformers_version(">=", _
 
 
 if _CAN_USE_FLASH_ATTN:
-    from flash_attn import flash_attn_func, flash_attn_varlen_func
-    from flash_attn.flash_attn_interface import _wrapped_flash_attn_backward, _wrapped_flash_attn_forward
+    try:
+        from flash_attn import flash_attn_func, flash_attn_varlen_func
+        from flash_attn.flash_attn_interface import _wrapped_flash_attn_backward, _wrapped_flash_attn_forward
+    except (ImportError, OSError, RuntimeError) as e:
+        # Handle ABI mismatch or other import failures gracefully.
+        # This can happen when flash_attn was compiled against a different PyTorch version.
+        logger.warning(f"flash_attn is installed but failed to import: {e}. Falling back to native PyTorch attention.")
+        _CAN_USE_FLASH_ATTN = False
+        flash_attn_func = None
+        flash_attn_varlen_func = None
+        _wrapped_flash_attn_backward = None
+        _wrapped_flash_attn_forward = None
 else:
     flash_attn_func = None
     flash_attn_varlen_func = None
@@ -83,26 +95,47 @@ else:
 
 
 if _CAN_USE_FLASH_ATTN_3:
-    from flash_attn_interface import flash_attn_func as flash_attn_3_func
-    from flash_attn_interface import flash_attn_varlen_func as flash_attn_3_varlen_func
+    try:
+        from flash_attn_interface import flash_attn_func as flash_attn_3_func
+        from flash_attn_interface import flash_attn_varlen_func as flash_attn_3_varlen_func
+    except (ImportError, OSError, RuntimeError) as e:
+        logger.warning(f"flash_attn_3 failed to import: {e}. Falling back to native attention.")
+        _CAN_USE_FLASH_ATTN_3 = False
+        flash_attn_3_func = None
+        flash_attn_3_varlen_func = None
 else:
     flash_attn_3_func = None
     flash_attn_3_varlen_func = None
 
 if _CAN_USE_AITER_ATTN:
-    from aiter import flash_attn_func as aiter_flash_attn_func
+    try:
+        from aiter import flash_attn_func as aiter_flash_attn_func
+    except (ImportError, OSError, RuntimeError) as e:
+        logger.warning(f"aiter failed to import: {e}. Falling back to native attention.")
+        _CAN_USE_AITER_ATTN = False
+        aiter_flash_attn_func = None
 else:
     aiter_flash_attn_func = None
 
 if _CAN_USE_SAGE_ATTN:
-    from sageattention import (
-        sageattn,
-        sageattn_qk_int8_pv_fp8_cuda,
-        sageattn_qk_int8_pv_fp8_cuda_sm90,
-        sageattn_qk_int8_pv_fp16_cuda,
-        sageattn_qk_int8_pv_fp16_triton,
-        sageattn_varlen,
-    )
+    try:
+        from sageattention import (
+            sageattn,
+            sageattn_qk_int8_pv_fp8_cuda,
+            sageattn_qk_int8_pv_fp8_cuda_sm90,
+            sageattn_qk_int8_pv_fp16_cuda,
+            sageattn_qk_int8_pv_fp16_triton,
+            sageattn_varlen,
+        )
+    except (ImportError, OSError, RuntimeError) as e:
+        logger.warning(f"sageattention failed to import: {e}. Falling back to native attention.")
+        _CAN_USE_SAGE_ATTN = False
+        sageattn = None
+        sageattn_qk_int8_pv_fp8_cuda = None
+        sageattn_qk_int8_pv_fp8_cuda_sm90 = None
+        sageattn_qk_int8_pv_fp16_cuda = None
+        sageattn_qk_int8_pv_fp16_triton = None
+        sageattn_varlen = None
 else:
     sageattn = None
     sageattn_qk_int8_pv_fp16_cuda = None
@@ -113,26 +146,48 @@ else:
 
 
 if _CAN_USE_FLEX_ATTN:
-    # We cannot import the flex_attention function from the package directly because it is expected (from the
-    # pytorch documentation) that the user may compile it. If we import directly, we will not have access to the
-    # compiled function.
-    import torch.nn.attention.flex_attention as flex_attention
+    try:
+        # We cannot import the flex_attention function from the package directly because it is expected (from the
+        # pytorch documentation) that the user may compile it. If we import directly, we will not have access to the
+        # compiled function.
+        import torch.nn.attention.flex_attention as flex_attention
+    except (ImportError, OSError, RuntimeError) as e:
+        logger.warning(f"flex_attention failed to import: {e}. Falling back to native attention.")
+        _CAN_USE_FLEX_ATTN = False
+        flex_attention = None
+else:
+    flex_attention = None
 
 
 if _CAN_USE_NPU_ATTN:
-    from torch_npu import npu_fusion_attention
+    try:
+        from torch_npu import npu_fusion_attention
+    except (ImportError, OSError, RuntimeError) as e:
+        logger.warning(f"torch_npu failed to import: {e}. Falling back to native attention.")
+        _CAN_USE_NPU_ATTN = False
+        npu_fusion_attention = None
 else:
     npu_fusion_attention = None
 
 
 if _CAN_USE_XLA_ATTN:
-    from torch_xla.experimental.custom_kernel import flash_attention as xla_flash_attention
+    try:
+        from torch_xla.experimental.custom_kernel import flash_attention as xla_flash_attention
+    except (ImportError, OSError, RuntimeError) as e:
+        logger.warning(f"torch_xla failed to import: {e}. Falling back to native attention.")
+        _CAN_USE_XLA_ATTN = False
+        xla_flash_attention = None
 else:
     xla_flash_attention = None
 
 
 if _CAN_USE_XFORMERS_ATTN:
-    import xformers.ops as xops
+    try:
+        import xformers.ops as xops
+    except (ImportError, OSError, RuntimeError) as e:
+        logger.warning(f"xformers failed to import: {e}. Falling back to native attention.")
+        _CAN_USE_XFORMERS_ATTN = False
+        xops = None
 else:
     xops = None
 
@@ -158,8 +213,6 @@ else:
     _register_fake = register_fake_no_op
 
 
-logger = get_logger(__name__)  # pylint: disable=invalid-name
-
 # TODO(aryan): Add support for the following:
 # - Sage Attention++
 # - block sparse, radial and other attention methods
@@ -276,7 +329,11 @@ class _HubKernelConfig:
 _HUB_KERNELS_REGISTRY: dict["AttentionBackendName", _HubKernelConfig] = {
     # TODO: temporary revision for now. Remove when merged upstream into `main`.
     AttentionBackendName._FLASH_3_HUB: _HubKernelConfig(
-        repo_id="kernels-community/flash-attn3", function_attr="flash_attn_func", revision="fake-ops-return-probs"
+        repo_id="kernels-community/flash-attn3",
+        function_attr="flash_attn_func",
+        revision="fake-ops-return-probs",
+        wrapped_forward_attr="flash_attn_interface._flash_attn_forward",
+        wrapped_backward_attr="flash_attn_interface._flash_attn_backward",
     ),
     AttentionBackendName._FLASH_3_VARLEN_HUB: _HubKernelConfig(
         repo_id="kernels-community/flash-attn3",
@@ -676,7 +733,7 @@ def _wrapped_flash_attn_3(
 ) -> tuple[torch.Tensor, torch.Tensor]:
     # Hardcoded for now because pytorch does not support tuple/int type hints
     window_size = (-1, -1)
-    out, lse, *_ = flash_attn_3_func(
+    result = flash_attn_3_func(
         q=q,
         k=k,
         v=v,
@@ -693,7 +750,9 @@ def _wrapped_flash_attn_3(
         pack_gqa=pack_gqa,
         deterministic=deterministic,
         sm_margin=sm_margin,
+        return_attn_probs=True,
     )
+    out, lse, *_ = result
     lse = lse.permute(0, 2, 1)
     return out, lse
 
@@ -1237,36 +1296,62 @@ def _flash_attention_3_hub_forward_op(
     if enable_gqa:
         raise ValueError("`enable_gqa` is not yet supported for flash-attn 3 hub kernels.")
 
-    func = _HUB_KERNELS_REGISTRY[AttentionBackendName._FLASH_3_HUB].kernel_fn
-    out = func(
-        q=query,
-        k=key,
-        v=value,
-        softmax_scale=scale,
+    config = _HUB_KERNELS_REGISTRY[AttentionBackendName._FLASH_3_HUB]
+    wrapped_forward_fn = config.wrapped_forward_fn
+    if wrapped_forward_fn is None:
+        raise RuntimeError(
+            "Flash attention 3 hub kernels must expose `flash_attn_interface._flash_attn_forward` "
+            "for context parallel execution."
+        )
+
+    if scale is None:
+        scale = query.shape[-1] ** (-0.5)
+
+    out, softmax_lse, *_ = wrapped_forward_fn(
+        query,
+        key,
+        value,
+        None,
+        None,  # k_new, v_new
+        None,  # qv
+        None,  # out
+        None,
+        None,
+        None,  # cu_seqlens_q/k/k_new
+        None,
+        None,  # seqused_q/k
+        None,
+        None,  # max_seqlen_q/k
+        None,
+        None,
+        None,  # page_table, kv_batch_idx, leftpad_k
+        None,
+        None,
+        None,  # rotary_cos/sin, seqlens_rotary
+        None,
+        None,
+        None,  # q_descale, k_descale, v_descale
+        scale,
         causal=is_causal,
-        qv=None,
-        q_descale=None,
-        k_descale=None,
-        v_descale=None,
-        window_size=window_size,
+        window_size_left=window_size[0],
+        window_size_right=window_size[1],
+        attention_chunk=0,
         softcap=softcap,
         num_splits=num_splits,
         pack_gqa=pack_gqa,
-        deterministic=deterministic,
         sm_margin=sm_margin,
-        return_attn_probs=return_lse,
     )
 
-    lse = None
-    if return_lse:
-        out, lse = out
-        lse = lse.permute(0, 2, 1).contiguous()
+    lse = softmax_lse.permute(0, 2, 1).contiguous() if return_lse else None
 
     if _save_ctx:
-        ctx.save_for_backward(query, key, value)
+        ctx.save_for_backward(query, key, value, out, softmax_lse)
         ctx.scale = scale
         ctx.is_causal = is_causal
-        ctx._hub_kernel = func
+        ctx.window_size = window_size
+        ctx.softcap = softcap
+        ctx.deterministic = deterministic
+        ctx.sm_margin = sm_margin
 
     return (out, lse) if return_lse else out
 
@@ -1275,54 +1360,49 @@ def _flash_attention_3_hub_backward_op(
     ctx: torch.autograd.function.FunctionCtx,
     grad_out: torch.Tensor,
     *args,
-    window_size: tuple[int, int] = (-1, -1),
-    softcap: float = 0.0,
-    num_splits: int = 1,
-    pack_gqa: bool | None = None,
-    deterministic: bool = False,
-    sm_margin: int = 0,
+    **kwargs,
 ):
-    query, key, value = ctx.saved_tensors
-    kernel_fn = ctx._hub_kernel
-    # NOTE: Unlike the FA2 hub kernel, the FA3 hub kernel does not expose separate wrapped forward/backward
-    # primitives (no `wrapped_forward_attr`/`wrapped_backward_attr` in its `_HubKernelConfig`). We
-    # therefore rerun the forward pass under `torch.enable_grad()` and differentiate through it with
-    # `torch.autograd.grad()`. This is a second forward pass during backward; it can be avoided once
-    # the FA3 hub exposes a dedicated fused backward kernel (analogous to `_wrapped_flash_attn_backward`
-    # in the FA2 hub), at which point this can be refactored to match `_flash_attention_hub_backward_op`.
-    with torch.enable_grad():
-        query_r = query.detach().requires_grad_(True)
-        key_r = key.detach().requires_grad_(True)
-        value_r = value.detach().requires_grad_(True)
-
-        out = kernel_fn(
-            q=query_r,
-            k=key_r,
-            v=value_r,
-            softmax_scale=ctx.scale,
-            causal=ctx.is_causal,
-            qv=None,
-            q_descale=None,
-            k_descale=None,
-            v_descale=None,
-            window_size=window_size,
-            softcap=softcap,
-            num_splits=num_splits,
-            pack_gqa=pack_gqa,
-            deterministic=deterministic,
-            sm_margin=sm_margin,
-            return_attn_probs=False,
+    config = _HUB_KERNELS_REGISTRY[AttentionBackendName._FLASH_3_HUB]
+    wrapped_backward_fn = config.wrapped_backward_fn
+    if wrapped_backward_fn is None:
+        raise RuntimeError(
+            "Flash attention 3 hub kernels must expose `flash_attn_interface._flash_attn_backward` "
+            "for context parallel execution."
         )
-        if isinstance(out, tuple):
-            out = out[0]
 
-        grad_query, grad_key, grad_value = torch.autograd.grad(
-            out,
-            (query_r, key_r, value_r),
-            grad_out,
-            retain_graph=False,
-            allow_unused=False,
-        )
+    query, key, value, out, softmax_lse = ctx.saved_tensors
+    grad_query = torch.empty_like(query)
+    grad_key = torch.empty_like(key)
+    grad_value = torch.empty_like(value)
+
+    wrapped_backward_fn(
+        grad_out,
+        query,
+        key,
+        value,
+        out,
+        softmax_lse,
+        None,
+        None,  # cu_seqlens_q, cu_seqlens_k
+        None,
+        None,  # seqused_q, seqused_k
+        None,
+        None,  # max_seqlen_q, max_seqlen_k
+        grad_query,
+        grad_key,
+        grad_value,
+        ctx.scale,
+        ctx.is_causal,
+        ctx.window_size[0],
+        ctx.window_size[1],
+        ctx.softcap,
+        ctx.deterministic,
+        ctx.sm_margin,
+    )
+
+    grad_query = grad_query[..., : grad_out.shape[-1]]
+    grad_key = grad_key[..., : grad_out.shape[-1]]
+    grad_value = grad_value[..., : grad_out.shape[-1]]
 
     return grad_query, grad_key, grad_value
 
@@ -2623,7 +2703,7 @@ def _flash_varlen_attention_3(
     key_packed = torch.cat(key_valid, dim=0)
     value_packed = torch.cat(value_valid, dim=0)
 
-    out, lse, *_ = flash_attn_3_varlen_func(
+    result = flash_attn_3_varlen_func(
         q=query_packed,
         k=key_packed,
         v=value_packed,
@@ -2633,7 +2713,13 @@ def _flash_varlen_attention_3(
         max_seqlen_k=max_seqlen_k,
         softmax_scale=scale,
         causal=is_causal,
+        return_attn_probs=return_lse,
     )
+    if isinstance(result, tuple):
+        out, lse, *_ = result
+    else:
+        out = result
+        lse = None
     out = out.unflatten(0, (batch_size, -1))
 
     return (out, lse) if return_lse else out

src/diffusers/models/controlnets/controlnet_cosmos.py

@@ -191,7 +191,12 @@ class CosmosControlNetModel(ModelMixin, ConfigMixin, FromOriginalModelMixin):
                 dim=1,
             )
 
-        control_hidden_states = torch.cat([control_hidden_states, torch.zeros_like(controls_latents[:, :1])], dim=1)
+        if condition_mask is not None:
+            control_hidden_states = torch.cat([control_hidden_states, condition_mask], dim=1)
+        else:
+            control_hidden_states = torch.cat(
+                [control_hidden_states, torch.zeros_like(controls_latents[:, :1])], dim=1
+            )
 
         padding_mask_resized = transforms.functional.resize(
             padding_mask, list(control_hidden_states.shape[-2:]), interpolation=transforms.InterpolationMode.NEAREST

src/diffusers/modular_pipelines/modular_pipeline.py

@@ -14,6 +14,7 @@
 import importlib
 import inspect
 import os
+import sys
 import traceback
 import warnings
 from collections import OrderedDict
@@ -28,10 +29,16 @@ from tqdm.auto import tqdm
 from typing_extensions import Self
 
 from ..configuration_utils import ConfigMixin, FrozenDict
-from ..pipelines.pipeline_loading_utils import _fetch_class_library_tuple, simple_get_class_obj
+from ..pipelines.pipeline_loading_utils import (
+    LOADABLE_CLASSES,
+    _fetch_class_library_tuple,
+    _unwrap_model,
+    simple_get_class_obj,
+)
 from ..utils import PushToHubMixin, is_accelerate_available, logging
 from ..utils.dynamic_modules_utils import get_class_from_dynamic_module, resolve_trust_remote_code
 from ..utils.hub_utils import load_or_create_model_card, populate_model_card
+from ..utils.torch_utils import is_compiled_module
 from .components_manager import ComponentsManager
 from .modular_pipeline_utils import (
     MODULAR_MODEL_CARD_TEMPLATE,
@@ -1633,7 +1640,14 @@ class ModularPipeline(ConfigMixin, PushToHubMixin):
                 blocks_class_name = self.default_blocks_name
             if blocks_class_name is not None:
                 diffusers_module = importlib.import_module("diffusers")
-                blocks_class = getattr(diffusers_module, blocks_class_name)
+                blocks_class = getattr(diffusers_module, blocks_class_name, None)
+                # If the blocks_class is not found or is a base class (e.g. SequentialPipelineBlocks saved by from_blocks_dict) with empty block_classes
+                # fall back to default_blocks_name
+                if blocks_class is None or not blocks_class.block_classes:
+                    blocks_class_name = self.default_blocks_name
+                    blocks_class = getattr(diffusers_module, blocks_class_name)
+
+            if blocks_class is not None:
                 blocks = blocks_class()
             else:
                 logger.warning(f"`blocks` is `None`, no default blocks class found for {self.__class__.__name__}")
@@ -1819,29 +1833,124 @@ class ModularPipeline(ConfigMixin, PushToHubMixin):
         )
         return pipeline
 
-    def save_pretrained(self, save_directory: str | os.PathLike, push_to_hub: bool = False, **kwargs):
+    def save_pretrained(
+        self,
+        save_directory: str | os.PathLike,
+        safe_serialization: bool = True,
+        variant: str | None = None,
+        max_shard_size: int | str | None = None,
+        push_to_hub: bool = False,
+        **kwargs,
+    ):
         """
-        Save the pipeline to a directory. It does not save components, you need to save them separately.
+        Save the pipeline and all its components to a directory, so that it can be re-loaded using the
+        [`~ModularPipeline.from_pretrained`] class method.
 
         Args:
             save_directory (`str` or `os.PathLike`):
-                Path to the directory where the pipeline will be saved.
-            push_to_hub (`bool`, optional):
-                Whether to push the pipeline to the huggingface hub.
-            **kwargs: Additional arguments passed to `save_config()` method
+                Directory to save the pipeline to. Will be created if it doesn't exist.
+            safe_serialization (`bool`, *optional*, defaults to `True`):
+                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
+            variant (`str`, *optional*):
+                If specified, weights are saved in the format `pytorch_model.<variant>.bin`.
+            max_shard_size (`int` or `str`, defaults to `None`):
+                The maximum size for a checkpoint before being sharded. Checkpoints shard will then be each of size
+                lower than this size. If expressed as a string, needs to be digits followed by a unit (like `"5GB"`).
+                If expressed as an integer, the unit is bytes.
+            push_to_hub (`bool`, *optional*, defaults to `False`):
+                Whether to push the pipeline to the Hugging Face model hub after saving it.
+            **kwargs: Additional keyword arguments:
+                - `overwrite_modular_index` (`bool`, *optional*, defaults to `False`):
+                    When saving a Modular Pipeline, its components in `modular_model_index.json` may reference repos
+                    different from the destination repo. Setting this to `True` updates all component references in
+                    `modular_model_index.json` so they point to the repo specified by `repo_id`.
+                - `repo_id` (`str`, *optional*):
+                    The repository ID to push the pipeline to. Defaults to the last component of `save_directory`.
+                - `commit_message` (`str`, *optional*):
+                    Commit message for the push to hub operation.
+                - `private` (`bool`, *optional*):
+                    Whether the repository should be private.
+                - `create_pr` (`bool`, *optional*, defaults to `False`):
+                    Whether to create a pull request instead of pushing directly.
+                - `token` (`str`, *optional*):
+                    The Hugging Face token to use for authentication.
         """
+        overwrite_modular_index = kwargs.pop("overwrite_modular_index", False)
+        repo_id = kwargs.pop("repo_id", save_directory.split(os.path.sep)[-1])
+
         if push_to_hub:
             commit_message = kwargs.pop("commit_message", None)
             private = kwargs.pop("private", None)
             create_pr = kwargs.pop("create_pr", False)
             token = kwargs.pop("token", None)
-            repo_id = kwargs.pop("repo_id", save_directory.split(os.path.sep)[-1])
             repo_id = create_repo(repo_id, exist_ok=True, private=private, token=token).repo_id
 
-            # Generate modular pipeline card content
-            card_content = generate_modular_model_card_content(self.blocks)
+        for component_name, component_spec in self._component_specs.items():
+            if component_spec.default_creation_method != "from_pretrained":
+                continue
 
-            # Create a new empty model card and eventually tag it
+            component = getattr(self, component_name, None)
+            if component is None:
+                continue
+
+            model_cls = component.__class__
+            if is_compiled_module(component):
+                component = _unwrap_model(component)
+                model_cls = component.__class__
+
+            save_method_name = None
+            for library_name, library_classes in LOADABLE_CLASSES.items():
+                if library_name in sys.modules:
+                    library = importlib.import_module(library_name)
+                else:
+                    logger.info(
+                        f"{library_name} is not installed. Cannot save {component_name} as {library_classes} from {library_name}"
+                    )
+                    continue
+
+                for base_class, save_load_methods in library_classes.items():
+                    class_candidate = getattr(library, base_class, None)
+                    if class_candidate is not None and issubclass(model_cls, class_candidate):
+                        save_method_name = save_load_methods[0]
+                        break
+                if save_method_name is not None:
+                    break
+
+            if save_method_name is None:
+                logger.warning(f"self.{component_name}={component} of type {type(component)} cannot be saved.")
+                continue
+
+            save_method = getattr(component, save_method_name)
+            save_method_signature = inspect.signature(save_method)
+            save_method_accept_safe = "safe_serialization" in save_method_signature.parameters
+            save_method_accept_variant = "variant" in save_method_signature.parameters
+            save_method_accept_max_shard_size = "max_shard_size" in save_method_signature.parameters
+
+            save_kwargs = {}
+            if save_method_accept_safe:
+                save_kwargs["safe_serialization"] = safe_serialization
+            if save_method_accept_variant:
+                save_kwargs["variant"] = variant
+            if save_method_accept_max_shard_size and max_shard_size is not None:
+                save_kwargs["max_shard_size"] = max_shard_size
+
+            component_save_path = os.path.join(save_directory, component_name)
+            save_method(component_save_path, **save_kwargs)
+
+            if component_name not in self.config:
+                continue
+
+            has_no_load_id = not hasattr(component, "_diffusers_load_id") or component._diffusers_load_id == "null"
+            if overwrite_modular_index or has_no_load_id:
+                library, class_name, component_spec_dict = self.config[component_name]
+                component_spec_dict["pretrained_model_name_or_path"] = repo_id if push_to_hub else save_directory
+                component_spec_dict["subfolder"] = component_name
+                self.register_to_config(**{component_name: (library, class_name, component_spec_dict)})
+
+        self.save_config(save_directory=save_directory)
+
+        if push_to_hub:
+            card_content = generate_modular_model_card_content(self.blocks)
             model_card = load_or_create_model_card(
                 repo_id,
                 token=token,
@@ -1850,13 +1959,8 @@ class ModularPipeline(ConfigMixin, PushToHubMixin):
                 is_modular=True,
             )
             model_card = populate_model_card(model_card, tags=card_content["tags"])
-
             model_card.save(os.path.join(save_directory, "README.md"))
 
-        # YiYi TODO: maybe order the json file to make it more readable: configs first, then components
-        self.save_config(save_directory=save_directory)
-
-        if push_to_hub:
             self._upload_folder(
                 save_directory,
                 repo_id,
@@ -2124,8 +2228,9 @@ class ModularPipeline(ConfigMixin, PushToHubMixin):
             ```
 
         Notes:
-            - Components with trained weights should be loaded with `AutoModel.from_pretrained()` or
-            `ComponentSpec.load()` so that loading specs are preserved for serialization.
+            - Components loaded with `AutoModel.from_pretrained()` or `ComponentSpec.load()` will have
+            loading specs preserved for serialization. Custom or locally loaded components without Hub references will
+            have their `modular_model_index.json` entries updated automatically during `save_pretrained()`.
             - ConfigMixin objects without weights (e.g., schedulers, guiders) can be passed directly.
         """
 
@@ -2147,14 +2252,6 @@ class ModularPipeline(ConfigMixin, PushToHubMixin):
                 new_component_spec = current_component_spec
                 if hasattr(self, name) and getattr(self, name) is not None:
                     logger.warning(f"ModularPipeline.update_components: setting {name} to None (spec unchanged)")
-            elif current_component_spec.default_creation_method == "from_pretrained" and not (
-                hasattr(component, "_diffusers_load_id") and component._diffusers_load_id is not None
-            ):
-                logger.warning(
-                    f"ModularPipeline.update_components: {name} has no valid _diffusers_load_id. "
-                    f"This will result in empty loading spec, use ComponentSpec.load() for proper specs"
-                )
-                new_component_spec = ComponentSpec(name=name, type_hint=type(component))
             else:
                 new_component_spec = ComponentSpec.from_component(name, component)
 

src/diffusers/modular_pipelines/modular_pipeline_utils.py

@@ -311,6 +311,12 @@ class ComponentSpec:
                 f"`type_hint` is required when loading a single file model but is missing for component: {self.name}"
             )
 
+        # `torch_dtype` is not an accepted parameter for tokenizers and processors.
+        # As a result, it gets stored in `init_kwargs`, which are written to the config
+        # during save. This causes JSON serialization to fail when saving the component.
+        if self.type_hint is not None and not issubclass(self.type_hint, torch.nn.Module):
+            kwargs.pop("torch_dtype", None)
+
         if self.type_hint is None:
             try:
                 from diffusers import AutoModel
@@ -328,6 +334,12 @@ class ComponentSpec:
                 else getattr(self.type_hint, "from_pretrained")
             )
 
+            # `torch_dtype` is not an accepted parameter for tokenizers and processors.
+            # As a result, it gets stored in `init_kwargs`, which are written to the config
+            # during save. This causes JSON serialization to fail when saving the component.
+            if not issubclass(self.type_hint, torch.nn.Module):
+                kwargs.pop("torch_dtype", None)
+
             try:
                 component = load_method(pretrained_model_name_or_path, **load_kwargs, **kwargs)
             except Exception as e:

src/diffusers/pipelines/cosmos/pipeline_cosmos2_5_transfer.py

@@ -17,9 +17,6 @@ from typing import Callable, Dict, List, Optional, Union
 import numpy as np
 import PIL.Image
 import torch
-import torchvision
-import torchvision.transforms
-import torchvision.transforms.functional
 from transformers import AutoTokenizer, Qwen2_5_VLForConditionalGeneration
 
 from ...callbacks import MultiPipelineCallbacks, PipelineCallback
@@ -54,11 +51,13 @@ else:
 logger = logging.get_logger(__name__)  # pylint: disable=invalid-name
 
 
-def _maybe_pad_video(video: torch.Tensor, num_frames: int):
+def _maybe_pad_or_trim_video(video: torch.Tensor, num_frames: int):
     n_pad_frames = num_frames - video.shape[2]
     if n_pad_frames > 0:
         last_frame = video[:, :, -1:, :, :]
         video = torch.cat((video, last_frame.repeat(1, 1, n_pad_frames, 1, 1)), dim=2)
+    elif num_frames < video.shape[2]:
+        video = video[:, :, :num_frames, :, :]
     return video
 
 
@@ -134,8 +133,8 @@ EXAMPLE_DOC_STRING = """
         >>> controls = [Image.fromarray(x.numpy()) for x in controls.permute(1, 2, 3, 0)]
         >>> export_to_video(controls, "edge_controlled_video_edge.mp4", fps=30)
 
+        >>> # Transfer inference with controls.
         >>> video = pipe(
-        ...     video=input_video[:num_frames],
         ...     controls=controls,
         ...     controls_conditioning_scale=1.0,
         ...     prompt=prompt,
@@ -149,7 +148,7 @@ EXAMPLE_DOC_STRING = """
 
 class Cosmos2_5_TransferPipeline(DiffusionPipeline):
     r"""
-    Pipeline for Cosmos Transfer2.5 base model.
+    Pipeline for Cosmos Transfer2.5, supporting auto-regressive inference.
 
     This model inherits from [`DiffusionPipeline`]. Check the superclass documentation for the generic methods
     implemented for all pipelines (downloading, saving, running on a particular device, etc.).
@@ -166,12 +165,14 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
             A scheduler to be used in combination with `transformer` to denoise the encoded image latents.
         vae ([`AutoencoderKLWan`]):
             Variational Auto-Encoder (VAE) Model to encode and decode videos to and from latent representations.
+        controlnet ([`CosmosControlNetModel`]):
+            ControlNet used to condition generation on control inputs.
     """
 
     model_cpu_offload_seq = "text_encoder->transformer->controlnet->vae"
     _callback_tensor_inputs = ["latents", "prompt_embeds", "negative_prompt_embeds"]
     # We mark safety_checker as optional here to get around some test failures, but it is not really optional
-    _optional_components = ["safety_checker", "controlnet"]
+    _optional_components = ["safety_checker"]
     _exclude_from_cpu_offload = ["safety_checker"]
 
     def __init__(
@@ -181,8 +182,8 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
         transformer: CosmosTransformer3DModel,
         vae: AutoencoderKLWan,
         scheduler: UniPCMultistepScheduler,
-        controlnet: Optional[CosmosControlNetModel],
-        safety_checker: CosmosSafetyChecker = None,
+        controlnet: CosmosControlNetModel,
+        safety_checker: Optional[CosmosSafetyChecker] = None,
     ):
         super().__init__()
 
@@ -384,10 +385,11 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
         num_frames_in: int = 93,
         num_frames_out: int = 93,
         do_classifier_free_guidance: bool = True,
-        dtype: torch.dtype | None = None,
-        device: torch.device | None = None,
-        generator: torch.Generator | list[torch.Generator] | None = None,
-        latents: torch.Tensor | None = None,
+        dtype: Optional[torch.dtype] = None,
+        device: Optional[torch.device] = None,
+        generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None,
+        latents: Optional[torch.Tensor] = None,
+        num_cond_latent_frames: int = 0,
     ) -> torch.Tensor:
         if isinstance(generator, list) and len(generator) != batch_size:
             raise ValueError(
@@ -402,10 +404,14 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
         W = width // self.vae_scale_factor_spatial
         shape = (B, C, T, H, W)
 
-        if num_frames_in == 0:
-            if latents is None:
-                latents = randn_tensor(shape, generator=generator, device=device, dtype=dtype)
+        if latents is not None:
+            if latents.shape[1:] != shape[1:]:
+                raise ValueError(f"Unexpected `latents` shape, got {latents.shape}, expected {shape}.")
+            latents = latents.to(device=device, dtype=dtype)
+        else:
+            latents = randn_tensor(shape, generator=generator, device=device, dtype=dtype)
 
+        if num_frames_in == 0:
             cond_mask = torch.zeros((B, 1, T, H, W), dtype=latents.dtype, device=latents.device)
             cond_indicator = torch.zeros((B, 1, T, 1, 1), dtype=latents.dtype, device=latents.device)
 
@@ -435,16 +441,12 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
             latents_std = self.latents_std.to(device=device, dtype=dtype)
             cond_latents = (cond_latents - latents_mean) / latents_std
 
-            if latents is None:
-                latents = randn_tensor(shape, generator=generator, device=device, dtype=dtype)
-            else:
-                latents = latents.to(device=device, dtype=dtype)
-
             padding_shape = (B, 1, T, H, W)
             ones_padding = latents.new_ones(padding_shape)
             zeros_padding = latents.new_zeros(padding_shape)
 
-            cond_indicator = latents.new_zeros(1, 1, latents.size(2), 1, 1)
+            cond_indicator = latents.new_zeros(B, 1, latents.size(2), 1, 1)
+            cond_indicator[:, :, 0:num_cond_latent_frames, :, :] = 1.0
             cond_mask = cond_indicator * ones_padding + (1 - cond_indicator) * zeros_padding
 
             return (
@@ -454,34 +456,7 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
                 cond_indicator,
             )
 
-    def _encode_controls(
-        self,
-        controls: Optional[torch.Tensor],
-        height: int,
-        width: int,
-        num_frames: int,
-        dtype: torch.dtype,
-        device: torch.device,
-        generator: torch.Generator | list[torch.Generator] | None,
-    ) -> Optional[torch.Tensor]:
-        if controls is None:
-            return None
-
-        control_video = self.video_processor.preprocess_video(controls, height, width)
-        control_video = _maybe_pad_video(control_video, num_frames)
-
-        control_video = control_video.to(device=device, dtype=self.vae.dtype)
-        control_latents = [
-            retrieve_latents(self.vae.encode(vid.unsqueeze(0)), generator=generator) for vid in control_video
-        ]
-        control_latents = torch.cat(control_latents, dim=0).to(dtype)
-
-        latents_mean = self.latents_mean.to(device=device, dtype=dtype)
-        latents_std = self.latents_std.to(device=device, dtype=dtype)
-        control_latents = (control_latents - latents_mean) / latents_std
-        return control_latents
-
-    # Copied from diffusers.pipelines.cosmos.pipeline_cosmos_text2world.CosmosTextToWorldPipeline.check_inputs
+    # Modified from diffusers.pipelines.cosmos.pipeline_cosmos_text2world.CosmosTextToWorldPipeline.check_inputs
     def check_inputs(
         self,
         prompt,
@@ -489,9 +464,25 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
         width,
         prompt_embeds=None,
         callback_on_step_end_tensor_inputs=None,
+        num_ar_conditional_frames=None,
+        num_ar_latent_conditional_frames=None,
+        num_frames_per_chunk=None,
+        num_frames=None,
+        conditional_frame_timestep=0.1,
     ):
-        if height % 16 != 0 or width % 16 != 0:
-            raise ValueError(f"`height` and `width` have to be divisible by 16 but are {height} and {width}.")
+        if width <= 0 or height <= 0 or height % 16 != 0 or width % 16 != 0:
+            raise ValueError(
+                f"`height` and `width` have to be divisible by 16 (& positive) but are {height} and {width}."
+            )
+
+        if num_frames is not None and num_frames <= 0:
+            raise ValueError(f"`num_frames` has to be a positive integer when provided but is {num_frames}.")
+
+        if conditional_frame_timestep < 0 or conditional_frame_timestep > 1:
+            raise ValueError(
+                "`conditional_frame_timestep` has to be a float in the [0, 1] interval but is "
+                f"{conditional_frame_timestep}."
+            )
 
         if callback_on_step_end_tensor_inputs is not None and not all(
             k in self._callback_tensor_inputs for k in callback_on_step_end_tensor_inputs
@@ -512,6 +503,46 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
         elif prompt is not None and (not isinstance(prompt, str) and not isinstance(prompt, list)):
             raise ValueError(f"`prompt` has to be of type `str` or `list` but is {type(prompt)}")
 
+        if num_ar_latent_conditional_frames is not None and num_ar_conditional_frames is not None:
+            raise ValueError(
+                "Provide only one of `num_ar_conditional_frames` or `num_ar_latent_conditional_frames`, not both."
+            )
+        if num_ar_latent_conditional_frames is None and num_ar_conditional_frames is None:
+            raise ValueError("Provide either `num_ar_conditional_frames` or `num_ar_latent_conditional_frames`.")
+        if num_ar_latent_conditional_frames is not None and num_ar_latent_conditional_frames < 0:
+            raise ValueError("`num_ar_latent_conditional_frames` must be >= 0.")
+        if num_ar_conditional_frames is not None and num_ar_conditional_frames < 0:
+            raise ValueError("`num_ar_conditional_frames` must be >= 0.")
+
+        if num_ar_latent_conditional_frames is not None:
+            num_ar_conditional_frames = max(
+                0, (num_ar_latent_conditional_frames - 1) * self.vae_scale_factor_temporal + 1
+            )
+
+        min_chunk_len = self.vae_scale_factor_temporal + 1
+        if num_frames_per_chunk < min_chunk_len:
+            logger.warning(f"{num_frames_per_chunk=} must be larger than {min_chunk_len=}, setting to min_chunk_len")
+            num_frames_per_chunk = min_chunk_len
+
+        max_frames_by_rope = None
+        if getattr(self.transformer.config, "max_size", None) is not None:
+            max_frames_by_rope = max(
+                size // patch
+                for size, patch in zip(self.transformer.config.max_size, self.transformer.config.patch_size)
+            )
+            if num_frames_per_chunk > max_frames_by_rope:
+                raise ValueError(
+                    f"{num_frames_per_chunk=} is too large for RoPE setting ({max_frames_by_rope=}). "
+                    "Please reduce `num_frames_per_chunk`."
+                )
+
+        if num_ar_conditional_frames >= num_frames_per_chunk:
+            raise ValueError(
+                f"{num_ar_conditional_frames=} must be smaller than {num_frames_per_chunk=} for chunked generation."
+            )
+
+        return num_frames_per_chunk
+
     @property
     def guidance_scale(self):
         return self._guidance_scale
@@ -536,23 +567,22 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
     @replace_example_docstring(EXAMPLE_DOC_STRING)
     def __call__(
         self,
-        image: PipelineImageInput | None = None,
-        video: List[PipelineImageInput] | None = None,
+        controls: PipelineImageInput | List[PipelineImageInput],
+        controls_conditioning_scale: Union[float, List[float]] = 1.0,
         prompt: Union[str, List[str]] | None = None,
         negative_prompt: Union[str, List[str]] = DEFAULT_NEGATIVE_PROMPT,
         height: int = 704,
-        width: int | None = None,
-        num_frames: int = 93,
+        width: Optional[int] = None,
+        num_frames: Optional[int] = None,
+        num_frames_per_chunk: int = 93,
         num_inference_steps: int = 36,
         guidance_scale: float = 3.0,
-        num_videos_per_prompt: Optional[int] = 1,
-        generator: torch.Generator | list[torch.Generator] | None = None,
-        latents: torch.Tensor | None = None,
-        controls: Optional[PipelineImageInput | List[PipelineImageInput]] = None,
-        controls_conditioning_scale: float | list[float] = 1.0,
-        prompt_embeds: torch.Tensor | None = None,
-        negative_prompt_embeds: torch.Tensor | None = None,
-        output_type: str = "pil",
+        num_videos_per_prompt: int = 1,
+        generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None,
+        latents: Optional[torch.Tensor] = None,
+        prompt_embeds: Optional[torch.Tensor] = None,
+        negative_prompt_embeds: Optional[torch.Tensor] = None,
+        output_type: Optional[str] = "pil",
         return_dict: bool = True,
         callback_on_step_end: Optional[
             Union[Callable[[int, int, Dict], None], PipelineCallback, MultiPipelineCallbacks]
@@ -560,24 +590,26 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
         callback_on_step_end_tensor_inputs: List[str] = ["latents"],
         max_sequence_length: int = 512,
         conditional_frame_timestep: float = 0.1,
+        num_ar_conditional_frames: Optional[int] = 1,
+        num_ar_latent_conditional_frames: Optional[int] = None,
     ):
         r"""
-        The call function to the pipeline for generation. Supports three modes:
+        `controls` drive the conditioning through ControlNet. Controls are assumed to be pre-processed, e.g. edge maps
+        are pre-computed.
 
-        - **Text2World**: `image=None`, `video=None`, `prompt` provided. Generates a world clip.
-        - **Image2World**: `image` provided, `video=None`, `prompt` provided. Conditions on a single frame.
-        - **Video2World**: `video` provided, `image=None`, `prompt` provided. Conditions on an input clip.
+        Setting `num_frames` will restrict the total number of frames output, if not provided or assigned to None
+        (default) then the number of output frames will match the input `controls`.
 
-        Set `num_frames=93` (default) to produce a world video, or `num_frames=1` to produce a single image frame (the
-        above in "*2Image mode").
-
-        Outputs follow `output_type` (e.g., `"pil"` returns a list of `num_frames` PIL images per prompt).
+        Auto-regressive inference is supported and thus a sliding window of `num_frames_per_chunk` frames are used per
+        denoising loop. In addition, when auto-regressive inference is performed, the previous
+        `num_ar_latent_conditional_frames` or `num_ar_conditional_frames` are used to condition the following denoising
+        inference loops.
 
         Args:
-            image (`PIL.Image.Image`, `np.ndarray`, `torch.Tensor`, *optional*):
-                Optional single image for Image2World conditioning. Must be `None` when `video` is provided.
-            video (`List[PIL.Image.Image]`, `np.ndarray`, `torch.Tensor`, *optional*):
-                Optional input video for Video2World conditioning. Must be `None` when `image` is provided.
+            controls (`PipelineImageInput`, `List[PipelineImageInput]`):
+                Control image or video input used by the ControlNet.
+            controls_conditioning_scale (`float` or `List[float]`, *optional*, defaults to `1.0`):
+                The scale factor(s) for the ControlNet outputs. A single float is broadcast to all control blocks.
             prompt (`str` or `List[str]`, *optional*):
                 The prompt or prompts to guide generation. Required unless `prompt_embeds` is supplied.
             height (`int`, defaults to `704`):
@@ -585,9 +617,10 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
             width (`int`, *optional*):
                 The width in pixels of the generated image. If not provided, this will be determined based on the
                 aspect ratio of the input and the provided height.
-            num_frames (`int`, defaults to `93`):
-                Number of output frames. Use `93` for world (video) generation; set to `1` to return a single frame.
-            num_inference_steps (`int`, defaults to `35`):
+            num_frames (`int`, *optional*):
+                Number of output frames. Defaults to `None` to output the same number of frames as the input
+                `controls`.
+            num_inference_steps (`int`, defaults to `36`):
                 The number of denoising steps. More denoising steps usually lead to a higher quality image at the
                 expense of slower inference.
             guidance_scale (`float`, defaults to `3.0`):
@@ -601,13 +634,9 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
                 A [`torch.Generator`](https://pytorch.org/docs/stable/generated/torch.Generator.html) to make
                 generation deterministic.
             latents (`torch.Tensor`, *optional*):
-                Pre-generated noisy latents sampled from a Gaussian distribution, to be used as inputs for image
-                generation. Can be used to tweak the same generation with different prompts. If not provided, a latents
-                tensor is generated by sampling using the supplied random `generator`.
-            controls (`PipelineImageInput`, `List[PipelineImageInput]`, *optional*):
-                Control image or video input used by the ControlNet. If `None`, ControlNet is skipped.
-            controls_conditioning_scale (`float` or `List[float]`, *optional*, defaults to `1.0`):
-                The scale factor(s) for the ControlNet outputs. A single float is broadcast to all control blocks.
+                Pre-generated noisy latents sampled from a Gaussian distribution, to be used as inputs. Can be used to
+                tweak the same generation with different prompts. If not provided, a latents tensor is generated by
+                sampling using the supplied random `generator`.
             prompt_embeds (`torch.Tensor`, *optional*):
                 Pre-generated text embeddings. Can be used to easily tweak text inputs, *e.g.* prompt weighting. If not
                 provided, text embeddings will be generated from `prompt` input argument.
@@ -630,7 +659,18 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
             max_sequence_length (`int`, defaults to `512`):
                 The maximum number of tokens in the prompt. If the prompt exceeds this length, it will be truncated. If
                 the prompt is shorter than this length, it will be padded.
+            num_ar_conditional_frames (`int`, *optional*, defaults to `1`):
+                Number of frames to condition on subsequent inference loops in auto-regressive inference, i.e. for the
+                second chunk and onwards. Only used if `num_ar_latent_conditional_frames` is `None`.
 
+                This is only used when auto-regressive inference is performed, i.e. when the number of frames in
+                controls is > num_frames_per_chunk
+            num_ar_latent_conditional_frames (`int`, *optional*):
+                Number of latent frames to condition on subsequent inference loops in auto-regressive inference, i.e.
+                for the second chunk and onwards. Only used if `num_ar_conditional_frames` is `None`.
+
+                This is only used when auto-regressive inference is performed, i.e. when the number of frames in
+                controls is > num_frames_per_chunk
         Examples:
 
         Returns:
@@ -650,21 +690,40 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
             callback_on_step_end_tensor_inputs = callback_on_step_end.tensor_inputs
 
         if width is None:
-            frame = image or video[0] if image or video else None
-            if frame is None and controls is not None:
-                frame = controls[0] if isinstance(controls, list) else controls
-                if isinstance(frame, (torch.Tensor, np.ndarray)) and len(frame.shape) == 4:
-                    frame = controls[0]
+            frame = controls[0] if isinstance(controls, list) else controls
+            if isinstance(frame, list):
+                frame = frame[0]
+            if isinstance(frame, (torch.Tensor, np.ndarray)):
+                if frame.ndim == 5:
+                    frame = frame[0, 0]
+                elif frame.ndim == 4:
+                    frame = frame[0]
 
-            if frame is None:
-                width = int((height + 16) * (1280 / 720))
-            elif isinstance(frame, PIL.Image.Image):
+            if isinstance(frame, PIL.Image.Image):
                 width = int((height + 16) * (frame.width / frame.height))
             else:
+                if frame.ndim != 3:
+                    raise ValueError("`controls` must contain 3D frames in CHW format.")
                 width = int((height + 16) * (frame.shape[2] / frame.shape[1]))  # NOTE: assuming C H W
 
-        # Check inputs. Raise error if not correct
-        self.check_inputs(prompt, height, width, prompt_embeds, callback_on_step_end_tensor_inputs)
+        num_frames_per_chunk = self.check_inputs(
+            prompt,
+            height,
+            width,
+            prompt_embeds,
+            callback_on_step_end_tensor_inputs,
+            num_ar_conditional_frames,
+            num_ar_latent_conditional_frames,
+            num_frames_per_chunk,
+            num_frames,
+            conditional_frame_timestep,
+        )
+
+        if num_ar_latent_conditional_frames is not None:
+            num_cond_latent_frames = num_ar_latent_conditional_frames
+            num_ar_conditional_frames = max(0, (num_cond_latent_frames - 1) * self.vae_scale_factor_temporal + 1)
+        else:
+            num_cond_latent_frames = max(0, (num_ar_conditional_frames - 1) // self.vae_scale_factor_temporal + 1)
 
         self._guidance_scale = guidance_scale
         self._current_timestep = None
@@ -709,102 +768,137 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
         vae_dtype = self.vae.dtype
         transformer_dtype = self.transformer.dtype
 
-        img_context = torch.zeros(
-            batch_size,
-            self.transformer.config.img_context_num_tokens,
-            self.transformer.config.img_context_dim_in,
-            device=prompt_embeds.device,
-            dtype=transformer_dtype,
-        )
-        encoder_hidden_states = (prompt_embeds, img_context)
-        neg_encoder_hidden_states = (negative_prompt_embeds, img_context)
-
-        num_frames_in = None
-        if image is not None:
-            if batch_size != 1:
-                raise ValueError(f"batch_size must be 1 for image input (given {batch_size})")
-
-            image = torchvision.transforms.functional.to_tensor(image).unsqueeze(0)
-            video = torch.cat([image, torch.zeros_like(image).repeat(num_frames - 1, 1, 1, 1)], dim=0)
-            video = video.unsqueeze(0)
-            num_frames_in = 1
-        elif video is None:
-            video = torch.zeros(batch_size, num_frames, 3, height, width, dtype=torch.uint8)
-            num_frames_in = 0
-        else:
-            num_frames_in = len(video)
-
-            if batch_size != 1:
-                raise ValueError(f"batch_size must be 1 for video input (given {batch_size})")
-
-        assert video is not None
-        video = self.video_processor.preprocess_video(video, height, width)
-
-        # pad with last frame (for video2world)
-        num_frames_out = num_frames
-        video = _maybe_pad_video(video, num_frames_out)
-        assert num_frames_in <= num_frames_out, f"expected ({num_frames_in=}) <= ({num_frames_out=})"
-
-        video = video.to(device=device, dtype=vae_dtype)
-
-        num_channels_latents = self.transformer.config.in_channels - 1
-        latents, cond_latent, cond_mask, cond_indicator = self.prepare_latents(
-            video=video,
-            batch_size=batch_size * num_videos_per_prompt,
-            num_channels_latents=num_channels_latents,
-            height=height,
-            width=width,
-            num_frames_in=num_frames_in,
-            num_frames_out=num_frames,
-            do_classifier_free_guidance=self.do_classifier_free_guidance,
-            dtype=torch.float32,
-            device=device,
-            generator=generator,
-            latents=latents,
-        )
-        cond_timestep = torch.ones_like(cond_indicator) * conditional_frame_timestep
-        cond_mask = cond_mask.to(transformer_dtype)
-
-        controls_latents = None
-        if controls is not None:
-            controls_latents = self._encode_controls(
-                controls,
-                height=height,
-                width=width,
-                num_frames=num_frames,
+        if getattr(self.transformer.config, "img_context_dim_in", None):
+            img_context = torch.zeros(
+                batch_size,
+                self.transformer.config.img_context_num_tokens,
+                self.transformer.config.img_context_dim_in,
+                device=prompt_embeds.device,
                 dtype=transformer_dtype,
-                device=device,
-                generator=generator,
             )
 
-        padding_mask = latents.new_zeros(1, 1, height, width, dtype=transformer_dtype)
+            if num_videos_per_prompt > 1:
+                img_context = img_context.repeat_interleave(num_videos_per_prompt, dim=0)
 
-        # Denoising loop
-        self.scheduler.set_timesteps(num_inference_steps, device=device)
-        timesteps = self.scheduler.timesteps
-        self._num_timesteps = len(timesteps)
-        num_warmup_steps = len(timesteps) - num_inference_steps * self.scheduler.order
+            encoder_hidden_states = (prompt_embeds, img_context)
+            neg_encoder_hidden_states = (negative_prompt_embeds, img_context)
+        else:
+            encoder_hidden_states = prompt_embeds
+            neg_encoder_hidden_states = negative_prompt_embeds
 
-        gt_velocity = (latents - cond_latent) * cond_mask
-        with self.progress_bar(total=num_inference_steps) as progress_bar:
-            for i, t in enumerate(timesteps):
-                if self.interrupt:
-                    continue
-
-                self._current_timestep = t.cpu().item()
-
-                # NOTE: assumes sigma(t) \in [0, 1]
-                sigma_t = (
-                    torch.tensor(self.scheduler.sigmas[i].item())
-                    .unsqueeze(0)
-                    .to(device=device, dtype=transformer_dtype)
+        control_video = self.video_processor.preprocess_video(controls, height, width)
+        if control_video.shape[0] != batch_size:
+            if control_video.shape[0] == 1:
+                control_video = control_video.repeat(batch_size, 1, 1, 1, 1)
+            else:
+                raise ValueError(
+                    f"Expected controls batch size {batch_size} to match prompt batch size, but got {control_video.shape[0]}."
                 )
 
-                in_latents = cond_mask * cond_latent + (1 - cond_mask) * latents
-                in_latents = in_latents.to(transformer_dtype)
-                in_timestep = cond_indicator * cond_timestep + (1 - cond_indicator) * sigma_t
-                control_blocks = None
-                if controls_latents is not None and self.controlnet is not None:
+        num_frames_out = control_video.shape[2]
+        if num_frames is not None:
+            num_frames_out = min(num_frames_out, num_frames)
+
+        control_video = _maybe_pad_or_trim_video(control_video, num_frames_out)
+
+        # chunk information
+        num_latent_frames_per_chunk = (num_frames_per_chunk - 1) // self.vae_scale_factor_temporal + 1
+        chunk_stride = num_frames_per_chunk - num_ar_conditional_frames
+        chunk_idxs = [
+            (start_idx, min(start_idx + num_frames_per_chunk, num_frames_out))
+            for start_idx in range(0, num_frames_out - num_ar_conditional_frames, chunk_stride)
+        ]
+
+        video_chunks = []
+        latents_mean = self.latents_mean.to(dtype=vae_dtype, device=device)
+        latents_std = self.latents_std.to(dtype=vae_dtype, device=device)
+
+        def decode_latents(latents):
+            latents = latents * latents_std + latents_mean
+            video = self.vae.decode(latents.to(dtype=self.vae.dtype, device=device), return_dict=False)[0]
+            return video
+
+        latents_arg = latents
+        initial_num_cond_latent_frames = 0
+        latent_chunks = []
+        num_chunks = len(chunk_idxs)
+        total_steps = num_inference_steps * num_chunks
+        with self.progress_bar(total=total_steps) as progress_bar:
+            for chunk_idx, (start_idx, end_idx) in enumerate(chunk_idxs):
+                if chunk_idx == 0:
+                    prev_output = torch.zeros((batch_size, num_frames_per_chunk, 3, height, width), dtype=vae_dtype)
+                    prev_output = self.video_processor.preprocess_video(prev_output, height, width)
+                else:
+                    prev_output = video_chunks[-1].clone()
+                    if num_ar_conditional_frames > 0:
+                        prev_output[:, :, :num_ar_conditional_frames] = prev_output[:, :, -num_ar_conditional_frames:]
+                        prev_output[:, :, num_ar_conditional_frames:] = -1  # -1 == 0 in processed video space
+                    else:
+                        prev_output.fill_(-1)
+
+                chunk_video = prev_output.to(device=device, dtype=vae_dtype)
+                chunk_video = _maybe_pad_or_trim_video(chunk_video, num_frames_per_chunk)
+                latents, cond_latent, cond_mask, cond_indicator = self.prepare_latents(
+                    video=chunk_video,
+                    batch_size=batch_size * num_videos_per_prompt,
+                    num_channels_latents=self.transformer.config.in_channels - 1,
+                    height=height,
+                    width=width,
+                    num_frames_in=chunk_video.shape[2],
+                    num_frames_out=num_frames_per_chunk,
+                    do_classifier_free_guidance=self.do_classifier_free_guidance,
+                    dtype=torch.float32,
+                    device=device,
+                    generator=generator,
+                    num_cond_latent_frames=initial_num_cond_latent_frames
+                    if chunk_idx == 0
+                    else num_cond_latent_frames,
+                    latents=latents_arg,
+                )
+                cond_mask = cond_mask.to(transformer_dtype)
+                cond_timestep = torch.ones_like(cond_indicator) * conditional_frame_timestep
+                padding_mask = latents.new_zeros(1, 1, height, width, dtype=transformer_dtype)
+
+                chunk_control_video = control_video[:, :, start_idx:end_idx, ...].to(
+                    device=device, dtype=self.vae.dtype
+                )
+                chunk_control_video = _maybe_pad_or_trim_video(chunk_control_video, num_frames_per_chunk)
+                if isinstance(generator, list):
+                    controls_latents = [
+                        retrieve_latents(self.vae.encode(chunk_control_video[i].unsqueeze(0)), generator=generator[i])
+                        for i in range(chunk_control_video.shape[0])
+                    ]
+                else:
+                    controls_latents = [
+                        retrieve_latents(self.vae.encode(vid.unsqueeze(0)), generator=generator)
+                        for vid in chunk_control_video
+                    ]
+                controls_latents = torch.cat(controls_latents, dim=0).to(transformer_dtype)
+
+                controls_latents = (controls_latents - latents_mean) / latents_std
+
+                # Denoising loop
+                self.scheduler.set_timesteps(num_inference_steps, device=device)
+                timesteps = self.scheduler.timesteps
+                self._num_timesteps = len(timesteps)
+
+                gt_velocity = (latents - cond_latent) * cond_mask
+                for i, t in enumerate(timesteps):
+                    if self.interrupt:
+                        continue
+
+                    self._current_timestep = t.cpu().item()
+
+                    # NOTE: assumes sigma(t) \in [0, 1]
+                    sigma_t = (
+                        torch.tensor(self.scheduler.sigmas[i].item())
+                        .unsqueeze(0)
+                        .to(device=device, dtype=transformer_dtype)
+                    )
+
+                    in_latents = cond_mask * cond_latent + (1 - cond_mask) * latents
+                    in_latents = in_latents.to(transformer_dtype)
+                    in_timestep = cond_indicator * cond_timestep + (1 - cond_indicator) * sigma_t
                     control_output = self.controlnet(
                         controls_latents=controls_latents,
                         latents=in_latents,
@@ -817,20 +911,18 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
                     )
                     control_blocks = control_output[0]
 
-                noise_pred = self.transformer(
-                    hidden_states=in_latents,
-                    timestep=in_timestep,
-                    encoder_hidden_states=encoder_hidden_states,
-                    block_controlnet_hidden_states=control_blocks,
-                    condition_mask=cond_mask,
-                    padding_mask=padding_mask,
-                    return_dict=False,
-                )[0]
-                noise_pred = gt_velocity + noise_pred * (1 - cond_mask)
+                    noise_pred = self.transformer(
+                        hidden_states=in_latents,
+                        timestep=in_timestep,
+                        encoder_hidden_states=encoder_hidden_states,
+                        block_controlnet_hidden_states=control_blocks,
+                        condition_mask=cond_mask,
+                        padding_mask=padding_mask,
+                        return_dict=False,
+                    )[0]
+                    noise_pred = gt_velocity + noise_pred * (1 - cond_mask)
 
-                if self.do_classifier_free_guidance:
-                    control_blocks = None
-                    if controls_latents is not None and self.controlnet is not None:
+                    if self.do_classifier_free_guidance:
                         control_output = self.controlnet(
                             controls_latents=controls_latents,
                             latents=in_latents,
@@ -843,46 +935,50 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
                         )
                         control_blocks = control_output[0]
 
-                    noise_pred_neg = self.transformer(
-                        hidden_states=in_latents,
-                        timestep=in_timestep,
-                        encoder_hidden_states=neg_encoder_hidden_states,  # NOTE: negative prompt
-                        block_controlnet_hidden_states=control_blocks,
-                        condition_mask=cond_mask,
-                        padding_mask=padding_mask,
-                        return_dict=False,
-                    )[0]
-                    # NOTE: replace velocity (noise_pred_neg) with gt_velocity for conditioning inputs only
-                    noise_pred_neg = gt_velocity + noise_pred_neg * (1 - cond_mask)
-                    noise_pred = noise_pred + self.guidance_scale * (noise_pred - noise_pred_neg)
+                        noise_pred_neg = self.transformer(
+                            hidden_states=in_latents,
+                            timestep=in_timestep,
+                            encoder_hidden_states=neg_encoder_hidden_states,  # NOTE: negative prompt
+                            block_controlnet_hidden_states=control_blocks,
+                            condition_mask=cond_mask,
+                            padding_mask=padding_mask,
+                            return_dict=False,
+                        )[0]
+                        # NOTE: replace velocity (noise_pred_neg) with gt_velocity for conditioning inputs only
+                        noise_pred_neg = gt_velocity + noise_pred_neg * (1 - cond_mask)
+                        noise_pred = noise_pred + self.guidance_scale * (noise_pred - noise_pred_neg)
 
-                latents = self.scheduler.step(noise_pred, t, latents, return_dict=False)[0]
+                    latents = self.scheduler.step(noise_pred, t, latents, return_dict=False)[0]
 
-                if callback_on_step_end is not None:
-                    callback_kwargs = {}
-                    for k in callback_on_step_end_tensor_inputs:
-                        callback_kwargs[k] = locals()[k]
-                    callback_outputs = callback_on_step_end(self, i, t, callback_kwargs)
+                    # call the callback, if provided
+                    if callback_on_step_end is not None:
+                        callback_kwargs = {}
+                        for k in callback_on_step_end_tensor_inputs:
+                            callback_kwargs[k] = locals()[k]
+                        callback_outputs = callback_on_step_end(self, i, t, callback_kwargs)
 
-                    latents = callback_outputs.pop("latents", latents)
-                    prompt_embeds = callback_outputs.pop("prompt_embeds", prompt_embeds)
-                    negative_prompt_embeds = callback_outputs.pop("negative_prompt_embeds", negative_prompt_embeds)
+                        latents = callback_outputs.pop("latents", latents)
+                        prompt_embeds = callback_outputs.pop("prompt_embeds", prompt_embeds)
+                        negative_prompt_embeds = callback_outputs.pop("negative_prompt_embeds", negative_prompt_embeds)
 
-                # call the callback, if provided
-                if i == len(timesteps) - 1 or ((i + 1) > num_warmup_steps and (i + 1) % self.scheduler.order == 0):
-                    progress_bar.update()
+                    if i == total_steps - 1 or ((i + 1) % self.scheduler.order == 0):
+                        progress_bar.update()
 
-                if XLA_AVAILABLE:
-                    xm.mark_step()
+                    if XLA_AVAILABLE:
+                        xm.mark_step()
+
+                video_chunks.append(decode_latents(latents).detach().cpu())
+                latent_chunks.append(latents.detach().cpu())
 
         self._current_timestep = None
 
         if not output_type == "latent":
-            latents_mean = self.latents_mean.to(latents.device, latents.dtype)
-            latents_std = self.latents_std.to(latents.device, latents.dtype)
-            latents = latents * latents_std + latents_mean
-            video = self.vae.decode(latents.to(self.vae.dtype), return_dict=False)[0]
-            video = self._match_num_frames(video, num_frames)
+            video_chunks = [
+                chunk[:, :, num_ar_conditional_frames:, ...] if chunk_idx != 0 else chunk
+                for chunk_idx, chunk in enumerate(video_chunks)
+            ]
+            video = torch.cat(video_chunks, dim=2)
+            video = video[:, :, :num_frames_out, ...]
 
             assert self.safety_checker is not None
             self.safety_checker.to(device)
@@ -899,7 +995,13 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
             video = torch.from_numpy(video).permute(0, 4, 1, 2, 3)
             video = self.video_processor.postprocess_video(video, output_type=output_type)
         else:
-            video = latents
+            latent_T = (num_frames_out - 1) // self.vae_scale_factor_temporal + 1
+            latent_chunks = [
+                chunk[:, :, num_cond_latent_frames:, ...] if chunk_idx != 0 else chunk
+                for chunk_idx, chunk in enumerate(latent_chunks)
+            ]
+            video = torch.cat(latent_chunks, dim=2)
+            video = video[:, :, :latent_T, ...]
 
         # Offload all models
         self.maybe_free_model_hooks()
@@ -908,19 +1010,3 @@ class Cosmos2_5_TransferPipeline(DiffusionPipeline):
             return (video,)
 
         return CosmosPipelineOutput(frames=video)
-
-    def _match_num_frames(self, video: torch.Tensor, target_num_frames: int) -> torch.Tensor:
-        if target_num_frames <= 0 or video.shape[2] == target_num_frames:
-            return video
-
-        frames_per_latent = max(self.vae_scale_factor_temporal, 1)
-        video = torch.repeat_interleave(video, repeats=frames_per_latent, dim=2)
-
-        current_frames = video.shape[2]
-        if current_frames < target_num_frames:
-            pad = video[:, :, -1:, :, :].repeat(1, 1, target_num_frames - current_frames, 1, 1)
-            video = torch.cat([video, pad], dim=2)
-        elif current_frames > target_num_frames:
-            video = video[:, :, :target_num_frames]
-
-        return video

src/diffusers/pipelines/ltx2/pipeline_ltx2_image2video.py

@@ -699,9 +699,13 @@ class LTX2ImageToVideoPipeline(DiffusionPipeline, FromSingleFileMixin, LTX2LoraL
         mask_shape = (batch_size, 1, num_frames, height, width)
 
         if latents is not None:
-            conditioning_mask = latents.new_zeros(mask_shape)
-            conditioning_mask[:, :, 0] = 1.0
             if latents.ndim == 5:
+                # conditioning_mask needs to the same shape as latents in two stages generation.
+                batch_size, _, num_frames, height, width = latents.shape
+                mask_shape = (batch_size, 1, num_frames, height, width)
+                conditioning_mask = latents.new_zeros(mask_shape)
+                conditioning_mask[:, :, 0] = 1.0
+
                 latents = self._normalize_latents(
                     latents, self.vae.latents_mean, self.vae.latents_std, self.vae.config.scaling_factor
                 )
@@ -710,6 +714,9 @@ class LTX2ImageToVideoPipeline(DiffusionPipeline, FromSingleFileMixin, LTX2LoraL
                 latents = self._pack_latents(
                     latents, self.transformer_spatial_patch_size, self.transformer_temporal_patch_size
                 )
+            else:
+                conditioning_mask = latents.new_zeros(mask_shape)
+                conditioning_mask[:, :, 0] = 1.0
             conditioning_mask = self._pack_latents(
                 conditioning_mask, self.transformer_spatial_patch_size, self.transformer_temporal_patch_size
             ).squeeze(-1)

src/diffusers/pipelines/z_image/pipeline_z_image.py

@@ -276,7 +276,7 @@ class ZImagePipeline(DiffusionPipeline, ZImageLoraLoaderMixin, FromSingleFileMix
 
     @property
     def do_classifier_free_guidance(self):
-        return self._guidance_scale > 1
+        return self._guidance_scale > 0
 
     @property
     def joint_attention_kwargs(self):

src/diffusers/schedulers/scheduling_ipndm.py

@@ -31,14 +31,18 @@ class IPNDMScheduler(SchedulerMixin, ConfigMixin):
     Args:
         num_train_timesteps (`int`, defaults to 1000):
             The number of diffusion steps to train the model.
-        trained_betas (`np.ndarray`, *optional*):
+        trained_betas (`np.ndarray` or `List[float]`, *optional*):
             Pass an array of betas directly to the constructor to bypass `beta_start` and `beta_end`.
     """
 
     order = 1
 
     @register_to_config
-    def __init__(self, num_train_timesteps: int = 1000, trained_betas: np.ndarray | list[float] | None = None):
+    def __init__(
+        self,
+        num_train_timesteps: int = 1000,
+        trained_betas: np.ndarray | list[float] | None = None,
+    ):
         # set `betas`, `alphas`, `timesteps`
         self.set_timesteps(num_train_timesteps)
 
@@ -56,21 +60,29 @@ class IPNDMScheduler(SchedulerMixin, ConfigMixin):
         self._begin_index = None
 
     @property
-    def step_index(self):
+    def step_index(self) -> int | None:
         """
         The index counter for current timestep. It will increase 1 after each scheduler step.
+
+        Returns:
+            `int` or `None`:
+                The index counter for current timestep.
         """
         return self._step_index
 
     @property
-    def begin_index(self):
+    def begin_index(self) -> int | None:
         """
         The index for the first timestep. It should be set from pipeline with `set_begin_index` method.
+
+        Returns:
+            `int` or `None`:
+                The index for the first timestep.
         """
         return self._begin_index
 
     # Copied from diffusers.schedulers.scheduling_dpmsolver_multistep.DPMSolverMultistepScheduler.set_begin_index
-    def set_begin_index(self, begin_index: int = 0):
+    def set_begin_index(self, begin_index: int = 0) -> None:
         """
         Sets the begin index for the scheduler. This function should be run from pipeline before the inference.
 
@@ -169,7 +181,7 @@ class IPNDMScheduler(SchedulerMixin, ConfigMixin):
         Args:
             model_output (`torch.Tensor`):
                 The direct output from learned diffusion model.
-            timestep (`int`):
+            timestep (`int` or `torch.Tensor`):
                 The current discrete timestep in the diffusion chain.
             sample (`torch.Tensor`):
                 A current instance of a sample created by the diffusion process.
@@ -228,7 +240,30 @@ class IPNDMScheduler(SchedulerMixin, ConfigMixin):
         """
         return sample
 
-    def _get_prev_sample(self, sample, timestep_index, prev_timestep_index, ets):
+    def _get_prev_sample(
+        self,
+        sample: torch.Tensor,
+        timestep_index: int,
+        prev_timestep_index: int,
+        ets: torch.Tensor,
+    ) -> torch.Tensor:
+        """
+        Predicts the previous sample based on the current sample, timestep indices, and running model outputs.
+
+        Args:
+            sample (`torch.Tensor`):
+                The current sample.
+            timestep_index (`int`):
+                Index of the current timestep in the schedule.
+            prev_timestep_index (`int`):
+                Index of the previous timestep in the schedule.
+            ets (`torch.Tensor`):
+                The running sequence of model outputs.
+
+        Returns:
+            `torch.Tensor`:
+                The predicted previous sample.
+        """
         alpha = self.alphas[timestep_index]
         sigma = self.betas[timestep_index]
 
@@ -240,5 +275,5 @@ class IPNDMScheduler(SchedulerMixin, ConfigMixin):
 
         return prev_sample
 
-    def __len__(self):
+    def __len__(self) -> int:
         return self.config.num_train_timesteps

src/diffusers/utils/dynamic_modules_utils.py

@@ -299,7 +299,10 @@ def get_cached_module_file(
     # Download and cache module_file from the repo `pretrained_model_name_or_path` of grab it if it's a local file.
     pretrained_model_name_or_path = str(pretrained_model_name_or_path)
 
-    module_file_or_url = os.path.join(pretrained_model_name_or_path, module_file)
+    if subfolder is not None:
+        module_file_or_url = os.path.join(pretrained_model_name_or_path, subfolder, module_file)
+    else:
+        module_file_or_url = os.path.join(pretrained_model_name_or_path, module_file)
 
     if os.path.isfile(module_file_or_url):
         resolved_module_file = module_file_or_url
@@ -384,7 +387,11 @@ def get_cached_module_file(
                 if not os.path.exists(submodule_path / module_folder):
                     os.makedirs(submodule_path / module_folder)
             module_needed = f"{module_needed}.py"
-            shutil.copyfile(os.path.join(pretrained_model_name_or_path, module_needed), submodule_path / module_needed)
+            if subfolder is not None:
+                source_path = os.path.join(pretrained_model_name_or_path, subfolder, module_needed)
+            else:
+                source_path = os.path.join(pretrained_model_name_or_path, module_needed)
+            shutil.copyfile(source_path, submodule_path / module_needed)
     else:
         # Get the commit hash
         # TODO: we will get this info in the etag soon, so retrieve it from there and not here.

tests/models/controlnets/test_models_controlnet_cosmos.py

@@ -131,6 +131,26 @@ class CosmosControlNetModelTests(ModelTesterMixin, unittest.TestCase):
         self.assertIsInstance(output[0], list)
         self.assertEqual(len(output[0]), init_dict["n_controlnet_blocks"])
 
+    def test_condition_mask_changes_output(self):
+        """Test that condition mask affects control outputs."""
+        init_dict, inputs_dict = self.prepare_init_args_and_inputs_for_common()
+        model = self.model_class(**init_dict)
+        model.to(torch_device)
+        model.eval()
+
+        inputs_no_mask = dict(inputs_dict)
+        inputs_no_mask["condition_mask"] = torch.zeros_like(inputs_dict["condition_mask"])
+
+        with torch.no_grad():
+            output_no_mask = model(**inputs_no_mask)
+            output_with_mask = model(**inputs_dict)
+
+        self.assertEqual(len(output_no_mask.control_block_samples), len(output_with_mask.control_block_samples))
+        for no_mask_tensor, with_mask_tensor in zip(
+            output_no_mask.control_block_samples, output_with_mask.control_block_samples
+        ):
+            self.assertFalse(torch.allclose(no_mask_tensor, with_mask_tensor))
+
     def test_conditioning_scale_single(self):
         """Test that a single conditioning scale is broadcast to all blocks."""
         init_dict, inputs_dict = self.prepare_init_args_and_inputs_for_common()

tests/models/test_models_auto.py

@@ -1,9 +1,15 @@
+import json
+import os
+import tempfile
 import unittest
 from unittest.mock import MagicMock, patch
 
+import torch
 from transformers import CLIPTextModel, LongformerModel
 
+from diffusers import ConfigMixin
 from diffusers.models import AutoModel, UNet2DConditionModel
+from diffusers.models.modeling_utils import ModelMixin
 
 
 class TestAutoModel(unittest.TestCase):
@@ -35,6 +41,45 @@ class TestAutoModel(unittest.TestCase):
         )
         assert isinstance(model, CLIPTextModel)
 
+    def test_load_dynamic_module_from_local_path_with_subfolder(self):
+        CUSTOM_MODEL_CODE = (
+            "import torch\n"
+            "from diffusers import ModelMixin, ConfigMixin\n"
+            "from diffusers.configuration_utils import register_to_config\n"
+            "\n"
+            "class CustomModel(ModelMixin, ConfigMixin):\n"
+            "    @register_to_config\n"
+            "    def __init__(self, hidden_size=8):\n"
+            "        super().__init__()\n"
+            "        self.linear = torch.nn.Linear(hidden_size, hidden_size)\n"
+            "\n"
+            "    def forward(self, x):\n"
+            "        return self.linear(x)\n"
+        )
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            subfolder = "custom_model"
+            model_dir = os.path.join(tmpdir, subfolder)
+            os.makedirs(model_dir)
+
+            with open(os.path.join(model_dir, "modeling.py"), "w") as f:
+                f.write(CUSTOM_MODEL_CODE)
+
+            config = {
+                "_class_name": "CustomModel",
+                "_diffusers_version": "0.0.0",
+                "auto_map": {"AutoModel": "modeling.CustomModel"},
+                "hidden_size": 8,
+            }
+            with open(os.path.join(model_dir, "config.json"), "w") as f:
+                json.dump(config, f)
+
+            torch.save({}, os.path.join(model_dir, "diffusion_pytorch_model.bin"))
+
+            model = AutoModel.from_pretrained(tmpdir, subfolder=subfolder, trust_remote_code=True)
+            assert model.__class__.__name__ == "CustomModel"
+            assert model.config["hidden_size"] == 8
+
 
 class TestAutoModelFromConfig(unittest.TestCase):
     @patch(
@@ -100,3 +145,51 @@ class TestAutoModelFromConfig(unittest.TestCase):
     def test_from_config_raises_on_none(self):
         with self.assertRaises(ValueError, msg="Please provide a `pretrained_model_name_or_path_or_dict`"):
             AutoModel.from_config(None)
+
+
+class TestRegisterForAutoClass(unittest.TestCase):
+    def test_register_for_auto_class_sets_attribute(self):
+        class DummyModel(ModelMixin, ConfigMixin):
+            config_name = "config.json"
+
+        DummyModel.register_for_auto_class("AutoModel")
+        self.assertEqual(DummyModel._auto_class, "AutoModel")
+
+    def test_register_for_auto_class_rejects_unsupported(self):
+        class DummyModel(ModelMixin, ConfigMixin):
+            config_name = "config.json"
+
+        with self.assertRaises(ValueError, msg="Only 'AutoModel' is supported"):
+            DummyModel.register_for_auto_class("AutoPipeline")
+
+    def test_auto_map_in_saved_config(self):
+        class DummyModel(ModelMixin, ConfigMixin):
+            config_name = "config.json"
+
+        DummyModel.register_for_auto_class("AutoModel")
+        model = DummyModel()
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            model.save_config(tmpdir)
+            config_path = os.path.join(tmpdir, "config.json")
+            with open(config_path, "r") as f:
+                config = json.load(f)
+
+        self.assertIn("auto_map", config)
+        self.assertIn("AutoModel", config["auto_map"])
+        module_name = DummyModel.__module__.split(".")[-1]
+        self.assertEqual(config["auto_map"]["AutoModel"], f"{module_name}.DummyModel")
+
+    def test_no_auto_map_without_register(self):
+        class DummyModel(ModelMixin, ConfigMixin):
+            config_name = "config.json"
+
+        model = DummyModel()
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            model.save_config(tmpdir)
+            config_path = os.path.join(tmpdir, "config.json")
+            with open(config_path, "r") as f:
+                config = json.load(f)
+
+        self.assertNotIn("auto_map", config)

tests/modular_pipelines/test_modular_pipelines_common.py

@@ -1,4 +1,6 @@
 import gc
+import json
+import os
 import tempfile
 from typing import Callable
 
@@ -349,6 +351,33 @@ class ModularPipelineTesterMixin:
 
         assert torch.abs(image_slices[0] - image_slices[1]).max() < 1e-3
 
+    def test_modular_index_consistency(self):
+        pipe = self.get_pipeline()
+        components_spec = pipe._component_specs
+        components = sorted(components_spec.keys())
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            pipe.save_pretrained(tmpdir)
+            index_file = os.path.join(tmpdir, "modular_model_index.json")
+            assert os.path.exists(index_file)
+
+            with open(index_file) as f:
+                index_contents = json.load(f)
+
+            compulsory_keys = {"_blocks_class_name", "_class_name", "_diffusers_version"}
+            for k in compulsory_keys:
+                assert k in index_contents
+
+            to_check_attrs = {"pretrained_model_name_or_path", "revision", "subfolder"}
+            for component in components:
+                spec = components_spec[component]
+                for attr in to_check_attrs:
+                    if getattr(spec, "pretrained_model_name_or_path", None) is not None:
+                        for attr in to_check_attrs:
+                            assert component in index_contents, f"{component} should be present in index but isn't."
+                            attr_value_from_index = index_contents[component][2][attr]
+                            assert getattr(spec, attr) == attr_value_from_index
+
     def test_workflow_map(self):
         blocks = self.pipeline_blocks_class()
         if blocks._workflow_map is None:
@@ -699,3 +728,103 @@ class TestLoadComponentsSkipBehavior:
 
         # Verify test_component was not loaded
         assert not hasattr(pipe, "test_component") or pipe.test_component is None
+
+
+class TestCustomModelSavePretrained:
+    def test_save_pretrained_updates_index_for_local_model(self, tmp_path):
+        """When a component without _diffusers_load_id (custom/local model) is saved,
+        modular_model_index.json should point to the save directory."""
+        import json
+
+        pipe = ModularPipeline.from_pretrained("hf-internal-testing/tiny-stable-diffusion-xl-pipe")
+        pipe.load_components(torch_dtype=torch.float32)
+
+        pipe.unet._diffusers_load_id = "null"
+
+        save_dir = str(tmp_path / "my-pipeline")
+        pipe.save_pretrained(save_dir)
+
+        with open(os.path.join(save_dir, "modular_model_index.json")) as f:
+            index = json.load(f)
+
+        _library, _cls, unet_spec = index["unet"]
+        assert unet_spec["pretrained_model_name_or_path"] == save_dir
+        assert unet_spec["subfolder"] == "unet"
+
+        _library, _cls, vae_spec = index["vae"]
+        assert vae_spec["pretrained_model_name_or_path"] == "hf-internal-testing/tiny-stable-diffusion-xl-pipe"
+
+    def test_save_pretrained_roundtrip_with_local_model(self, tmp_path):
+        """A pipeline with a custom/local model should be saveable and re-loadable with identical outputs."""
+        pipe = ModularPipeline.from_pretrained("hf-internal-testing/tiny-stable-diffusion-xl-pipe")
+        pipe.load_components(torch_dtype=torch.float32)
+
+        pipe.unet._diffusers_load_id = "null"
+
+        original_state_dict = pipe.unet.state_dict()
+
+        save_dir = str(tmp_path / "my-pipeline")
+        pipe.save_pretrained(save_dir)
+
+        loaded_pipe = ModularPipeline.from_pretrained(save_dir)
+        loaded_pipe.load_components(torch_dtype=torch.float32)
+
+        assert loaded_pipe.unet is not None
+        assert loaded_pipe.unet.__class__.__name__ == pipe.unet.__class__.__name__
+
+        loaded_state_dict = loaded_pipe.unet.state_dict()
+        assert set(original_state_dict.keys()) == set(loaded_state_dict.keys())
+        for key in original_state_dict:
+            assert torch.equal(original_state_dict[key], loaded_state_dict[key]), f"Mismatch in {key}"
+
+    def test_save_pretrained_overwrite_modular_index(self, tmp_path):
+        """With overwrite_modular_index=True, all component references should point to the save directory."""
+        import json
+
+        pipe = ModularPipeline.from_pretrained("hf-internal-testing/tiny-stable-diffusion-xl-pipe")
+        pipe.load_components(torch_dtype=torch.float32)
+
+        save_dir = str(tmp_path / "my-pipeline")
+        pipe.save_pretrained(save_dir, overwrite_modular_index=True)
+
+        with open(os.path.join(save_dir, "modular_model_index.json")) as f:
+            index = json.load(f)
+
+        for component_name in ["unet", "vae", "text_encoder", "text_encoder_2"]:
+            if component_name not in index:
+                continue
+            _library, _cls, spec = index[component_name]
+            assert spec["pretrained_model_name_or_path"] == save_dir, (
+                f"{component_name} should point to save dir but got {spec['pretrained_model_name_or_path']}"
+            )
+            assert spec["subfolder"] == component_name
+
+        loaded_pipe = ModularPipeline.from_pretrained(save_dir)
+        loaded_pipe.load_components(torch_dtype=torch.float32)
+
+        assert loaded_pipe.unet is not None
+        assert loaded_pipe.vae is not None
+
+
+class TestModularPipelineInitFallback:
+    """Test that ModularPipeline.__init__ falls back to default_blocks_name when
+    _blocks_class_name is a base class (e.g. SequentialPipelineBlocks saved by from_blocks_dict)."""
+
+    def test_init_fallback_when_blocks_class_name_is_base_class(self, tmp_path):
+        # 1. Load pipeline and get a workflow (returns a base SequentialPipelineBlocks)
+        pipe = ModularPipeline.from_pretrained("hf-internal-testing/tiny-stable-diffusion-xl-pipe")
+        t2i_blocks = pipe.blocks.get_workflow("text2image")
+        assert t2i_blocks.__class__.__name__ == "SequentialPipelineBlocks"
+
+        # 2. Use init_pipeline to create a new pipeline from the workflow blocks
+        t2i_pipe = t2i_blocks.init_pipeline("hf-internal-testing/tiny-stable-diffusion-xl-pipe")
+
+        # 3. Save and reload — the saved config will have _blocks_class_name="SequentialPipelineBlocks"
+        save_dir = str(tmp_path / "pipeline")
+        t2i_pipe.save_pretrained(save_dir)
+        loaded_pipe = ModularPipeline.from_pretrained(save_dir)
+
+        # 4. Verify it fell back to default_blocks_name and has correct blocks
+        assert loaded_pipe.__class__.__name__ == pipe.__class__.__name__
+        assert loaded_pipe._blocks.__class__.__name__ == pipe._blocks.__class__.__name__
+        assert len(loaded_pipe._blocks.sub_blocks) == len(pipe._blocks.sub_blocks)

tests/pipelines/cosmos/test_cosmos2_5_transfer.py

@@ -55,7 +55,7 @@ class Cosmos2_5_TransferWrapper(Cosmos2_5_TransferPipeline):
 class Cosmos2_5_TransferPipelineFastTests(PipelineTesterMixin, unittest.TestCase):
     pipeline_class = Cosmos2_5_TransferWrapper
     params = TEXT_TO_IMAGE_PARAMS - {"cross_attention_kwargs"}
-    batch_params = TEXT_TO_IMAGE_BATCH_PARAMS
+    batch_params = TEXT_TO_IMAGE_BATCH_PARAMS.union({"controls"})
     image_params = TEXT_TO_IMAGE_IMAGE_PARAMS
     image_latents_params = TEXT_TO_IMAGE_IMAGE_PARAMS
     required_optional_params = frozenset(
@@ -176,15 +176,19 @@ class Cosmos2_5_TransferPipelineFastTests(PipelineTesterMixin, unittest.TestCase
         else:
             generator = torch.Generator(device=device).manual_seed(seed)
 
+        controls_generator = torch.Generator(device="cpu").manual_seed(seed)
+
         inputs = {
             "prompt": "dance monkey",
             "negative_prompt": "bad quality",
+            "controls": [torch.randn(3, 32, 32, generator=controls_generator) for _ in range(5)],
             "generator": generator,
             "num_inference_steps": 2,
             "guidance_scale": 3.0,
             "height": 32,
             "width": 32,
             "num_frames": 3,
+            "num_frames_per_chunk": 16,
             "max_sequence_length": 16,
             "output_type": "pt",
         }
@@ -212,6 +216,56 @@ class Cosmos2_5_TransferPipelineFastTests(PipelineTesterMixin, unittest.TestCase
         self.assertEqual(generated_video.shape, (3, 3, 32, 32))
         self.assertTrue(torch.isfinite(generated_video).all())
 
+    def test_inference_autoregressive_multi_chunk(self):
+        device = "cpu"
+
+        components = self.get_dummy_components()
+        pipe = self.pipeline_class(**components)
+        pipe.to(device)
+        pipe.set_progress_bar_config(disable=None)
+
+        inputs = self.get_dummy_inputs(device)
+        inputs["num_frames"] = 5
+        inputs["num_frames_per_chunk"] = 3
+        inputs["num_ar_conditional_frames"] = 1
+
+        video = pipe(**inputs).frames
+        generated_video = video[0]
+        self.assertEqual(generated_video.shape, (5, 3, 32, 32))
+        self.assertTrue(torch.isfinite(generated_video).all())
+
+    def test_inference_autoregressive_multi_chunk_no_condition_frames(self):
+        device = "cpu"
+
+        components = self.get_dummy_components()
+        pipe = self.pipeline_class(**components)
+        pipe.to(device)
+        pipe.set_progress_bar_config(disable=None)
+
+        inputs = self.get_dummy_inputs(device)
+        inputs["num_frames"] = 5
+        inputs["num_frames_per_chunk"] = 3
+        inputs["num_ar_conditional_frames"] = 0
+
+        video = pipe(**inputs).frames
+        generated_video = video[0]
+        self.assertEqual(generated_video.shape, (5, 3, 32, 32))
+        self.assertTrue(torch.isfinite(generated_video).all())
+
+    def test_num_frames_per_chunk_above_rope_raises(self):
+        device = "cpu"
+
+        components = self.get_dummy_components()
+        pipe = self.pipeline_class(**components)
+        pipe.to(device)
+        pipe.set_progress_bar_config(disable=None)
+
+        inputs = self.get_dummy_inputs(device)
+        inputs["num_frames_per_chunk"] = 17
+
+        with self.assertRaisesRegex(ValueError, "too large for RoPE setting"):
+            pipe(**inputs)
+
     def test_inference_with_controls(self):
         """Test inference with control inputs (ControlNet)."""
         device = "cpu"
@@ -222,13 +276,13 @@ class Cosmos2_5_TransferPipelineFastTests(PipelineTesterMixin, unittest.TestCase
         pipe.set_progress_bar_config(disable=None)
 
         inputs = self.get_dummy_inputs(device)
-        # Add control video input - should be a video tensor
-        inputs["controls"] = [torch.randn(3, 3, 32, 32)]  # num_frames, channels, height, width
+        inputs["controls"] = [torch.randn(3, 32, 32) for _ in range(5)]  # list of 5 frames (C, H, W)
         inputs["controls_conditioning_scale"] = 1.0
+        inputs["num_frames"] = None
 
         video = pipe(**inputs).frames
         generated_video = video[0]
-        self.assertEqual(generated_video.shape, (3, 3, 32, 32))
+        self.assertEqual(generated_video.shape, (5, 3, 32, 32))
         self.assertTrue(torch.isfinite(generated_video).all())
 
     def test_callback_inputs(self):

tests/pipelines/ltx2/test_ltx2_image2video.py

@@ -24,7 +24,8 @@ from diffusers import (
     LTX2ImageToVideoPipeline,
     LTX2VideoTransformer3DModel,
 )
-from diffusers.pipelines.ltx2 import LTX2TextConnectors
+from diffusers.pipelines.ltx2 import LTX2LatentUpsamplePipeline, LTX2TextConnectors
+from diffusers.pipelines.ltx2.latent_upsampler import LTX2LatentUpsamplerModel
 from diffusers.pipelines.ltx2.vocoder import LTX2Vocoder
 
 from ...testing_utils import enable_full_determinism
@@ -174,6 +175,15 @@ class LTX2ImageToVideoPipelineFastTests(PipelineTesterMixin, unittest.TestCase):
 
         return components
 
+    def get_dummy_upsample_component(self, in_channels=4, mid_channels=32, num_blocks_per_stage=1):
+        upsampler = LTX2LatentUpsamplerModel(
+            in_channels=in_channels,
+            mid_channels=mid_channels,
+            num_blocks_per_stage=num_blocks_per_stage,
+        )
+
+        return upsampler
+
     def get_dummy_inputs(self, device, seed=0):
         if str(device).startswith("mps"):
             generator = torch.manual_seed(seed)
@@ -287,5 +297,60 @@ class LTX2ImageToVideoPipelineFastTests(PipelineTesterMixin, unittest.TestCase):
         assert torch.allclose(expected_video_slice, generated_video_slice, atol=1e-4, rtol=1e-4)
         assert torch.allclose(expected_audio_slice, generated_audio_slice, atol=1e-4, rtol=1e-4)
 
+    def test_two_stages_inference_with_upsampler(self):
+        device = "cpu"
+
+        components = self.get_dummy_components()
+        pipe = self.pipeline_class(**components)
+        pipe.to(device)
+        pipe.set_progress_bar_config(disable=None)
+
+        inputs = self.get_dummy_inputs(device)
+        inputs["output_type"] = "latent"
+        first_stage_output = pipe(**inputs)
+        video_latent = first_stage_output.frames
+        audio_latent = first_stage_output.audio
+
+        self.assertEqual(video_latent.shape, (1, 4, 3, 16, 16))
+        self.assertEqual(audio_latent.shape, (1, 2, 5, 2))
+        self.assertEqual(audio_latent.shape[1], components["vocoder"].config.out_channels)
+
+        upsampler = self.get_dummy_upsample_component(in_channels=video_latent.shape[1])
+        upsample_pipe = LTX2LatentUpsamplePipeline(vae=pipe.vae, latent_upsampler=upsampler)
+        upscaled_video_latent = upsample_pipe(latents=video_latent, output_type="latent", return_dict=False)[0]
+        self.assertEqual(upscaled_video_latent.shape, (1, 4, 3, 32, 32))
+
+        inputs["latents"] = upscaled_video_latent
+        inputs["audio_latents"] = audio_latent
+        inputs["output_type"] = "pt"
+        second_stage_output = pipe(**inputs)
+        video = second_stage_output.frames
+        audio = second_stage_output.audio
+
+        self.assertEqual(video.shape, (1, 5, 3, 64, 64))
+        self.assertEqual(audio.shape[0], 1)
+        self.assertEqual(audio.shape[1], components["vocoder"].config.out_channels)
+
+        # fmt: off
+        expected_video_slice = torch.tensor(
+            [
+                0.4497, 0.6757, 0.4219, 0.7686, 0.4525, 0.6483, 0.3969, 0.7404, 0.3541, 0.3039, 0.4592, 0.3521, 0.3665, 0.2785, 0.3336, 0.3079
+            ]
+        )
+        expected_audio_slice = torch.tensor(
+            [
+                0.0271, 0.0492, 0.1249, 0.1126, 0.1661, 0.1060, 0.1717, 0.0944, 0.0672, -0.0069, 0.0688, 0.0097, 0.0808, 0.1231, 0.0986, 0.0739
+            ]
+        )
+        # fmt: on
+
+        video = video.flatten()
+        audio = audio.flatten()
+        generated_video_slice = torch.cat([video[:8], video[-8:]])
+        generated_audio_slice = torch.cat([audio[:8], audio[-8:]])
+
+        assert torch.allclose(expected_video_slice, generated_video_slice, atol=1e-4, rtol=1e-4)
+        assert torch.allclose(expected_audio_slice, generated_audio_slice, atol=1e-4, rtol=1e-4)
+
     def test_inference_batch_single_identical(self):
         self._test_inference_batch_single_identical(batch_size=2, expected_max_diff=2e-2)

tests/quantization/torchao/test_torchao.py

@@ -74,7 +74,7 @@ if is_torchao_available():
 
 @require_torch
 @require_torch_accelerator
-@require_torchao_version_greater_or_equal("0.7.0")
+@require_torchao_version_greater_or_equal("0.14.0")
 class TorchAoConfigTest(unittest.TestCase):
     def test_to_dict(self):
         """
@@ -132,7 +132,7 @@ class TorchAoConfigTest(unittest.TestCase):
 # Slices for these tests have been obtained on our aws-g6e-xlarge-plus runners
 @require_torch
 @require_torch_accelerator
-@require_torchao_version_greater_or_equal("0.7.0")
+@require_torchao_version_greater_or_equal("0.14.0")
 class TorchAoTest(unittest.TestCase):
     def tearDown(self):
         gc.collect()
@@ -587,7 +587,7 @@ class TorchAoTest(unittest.TestCase):
 # Slices for these tests have been obtained on our aws-g6e-xlarge-plus runners
 @require_torch
 @require_torch_accelerator
-@require_torchao_version_greater_or_equal("0.7.0")
+@require_torchao_version_greater_or_equal("0.14.0")
 class TorchAoSerializationTest(unittest.TestCase):
     model_name = "hf-internal-testing/tiny-flux-pipe"
 
@@ -698,23 +698,22 @@ class TorchAoSerializationTest(unittest.TestCase):
         self._check_serialization_expected_slice(quant_method, quant_method_kwargs, expected_slice, device)
 
 
-@require_torchao_version_greater_or_equal("0.7.0")
+@require_torchao_version_greater_or_equal("0.14.0")
 class TorchAoCompileTest(QuantCompileTests, unittest.TestCase):
     @property
     def quantization_config(self):
         return PipelineQuantizationConfig(
-            quant_mapping={
-                "transformer": TorchAoConfig(quant_type="int8_weight_only"),
-            },
+            quant_mapping={"transformer": TorchAoConfig(Int8WeightOnlyConfig())},
         )
 
-    @unittest.skip(
-        "Changing the device of AQT tensor with module._apply (called from doing module.to() in accelerate) does not work "
-        "when compiling."
-    )
     def test_torch_compile_with_cpu_offload(self):
+        pipe = self._init_pipeline(self.quantization_config, torch.bfloat16)
+        pipe.enable_model_cpu_offload()
+        # No compilation because it fails with:
         # RuntimeError: _apply(): Couldn't swap Linear.weight
-        super().test_torch_compile_with_cpu_offload()
+
+        # small resolutions to ensure speedy execution.
+        pipe("a dog", num_inference_steps=2, max_sequence_length=16, height=256, width=256)
 
     @parameterized.expand([False, True])
     @unittest.skip(
@@ -745,7 +744,7 @@ class TorchAoCompileTest(QuantCompileTests, unittest.TestCase):
 # Slices for these tests have been obtained on our aws-g6e-xlarge-plus runners
 @require_torch
 @require_torch_accelerator
-@require_torchao_version_greater_or_equal("0.7.0")
+@require_torchao_version_greater_or_equal("0.14.0")
 @slow
 @nightly
 class SlowTorchAoTests(unittest.TestCase):
@@ -907,7 +906,7 @@ class SlowTorchAoTests(unittest.TestCase):
 
 @require_torch
 @require_torch_accelerator
-@require_torchao_version_greater_or_equal("0.7.0")
+@require_torchao_version_greater_or_equal("0.14.0")
 @slow
 @nightly
 class SlowTorchAoPreserializedModelTests(unittest.TestCase):