Enable multimodal model support for RL training

[nancyjlau]

Added processor support that is tested to work for multimodal VL models like Qwen2.5-VL and Qwen3-VL. Changes include updating the verl submodule to latest main (which includes multimodal support from PRs #2146 and #2398), adding hf_processor loading in rLLM trainers (train_workflow_pipeline.py and train_agent_ppo.py), and bumping transformers to >=4.57.0 for Qwen3-VL.

I have tested Qwen/Qwen2.5-VL-3B-Instruct and successfully loaded Qwen2_5_VLProcessor. Qwen3-VL models are supported with transformers >=4.57.0.

Closes #242

[jeffreysijuntan]

Thanks for your PR! This feature would be really helpful. Can you write a simple training example that can verify it?

[yuzeng0-0]

Added processor support that is tested to work for multimodal VL models like Qwen2.5-VL and Qwen3-VL. Changes include updating the verl submodule to latest main (which includes multimodal support from PRs #2146 and #2398), adding hf_processor loading in rLLM trainers (train_workflow_pipeline.py and train_agent_ppo.py), and bumping transformers to >=4.57.0 for Qwen3-VL.

I have tested `Qwen/Qwen2.5-VL-3B-Instruct` and successfully loaded `Qwen2_5_VLProcessor`. Qwen3-VL models are supported with `transformers >=4.57.0`.

Closes #242

Could you please provide a test startup script as well as the training dataset used for testing? Thanks!

[huaiyizhao]

I think we need vllm>=0.11.0 or sglang>=0.5.3 to support qwen3-vl rollout

[nancyjlau]

Working on getting a environment that works again for examples but yes, this needs an updated sglang version in order to get it to work. Currently in dependency hell trying to recreate a working environment for qwen3-vl.

[jeffreysijuntan]

Does merging this into the nightly version helps? It is currently using verl==0.6.0, so the sglang/vllm version is newer.

[huaiyizhao]

For vllm==0.11.0, this works for me volcengine/verl#3934

[nancyjlau]

You were able to get it working on vllm==0.11.0? Could you share the details on how you did that?

I'm currently facing these issues:
- torch 2.6.0+cu124 is the only version that works with flash-attn 2.7.4.post1
- flash attention 2.7.4.post is required for Qwen-3VL
- vllm 0.8.5 is the only version compatible with torch 2.6.0+cu124, but is incompatible with current verl version because of v1 API issues

For SGLang, I was able to get it training until I hit a OOM error on a single GPU, and then am unable to replicate the setup with multiple H100s.

[Osilly]

@nancyjlau I would like to know if you can start the RLLM training in the latest version of verl. I tried to replace vert-0.5.0 with the latest one, but it was suspended. As a result, the task pends after outputting the logs:

[36m(vLLMHttpServer pid=1793, ip=10.144.204.96)�[0m INFO:2025-10-28 04:50:43,457:replica_rank=1, node_rank=0, nnodes=1, get worker zmq addresses: ['ipc:///tmp/verl_vllm_zmq_2096_root.ipc', 'ipc:///tmp/verl_vllm_zmq_2097_root.ipc', 'ipc:///tmp/verl_vllm_zmq_2098_root.ipc', 'ipc:///tmp/verl_vllm_zmq_2099_root.ipc', 'ipc:///tmp/verl_vllm_zmq_2100_root.ipc', 'ipc:///tmp/verl_vllm_zmq_2101_root.ipc', 'ipc:///tmp/verl_vllm_zmq_2102_root.ipc', 'ipc:///tmp/verl_vllm_zmq_2103_root.ipc']
�[36m(vLLMHttpServer pid=27028)�[0m INFO:2025-10-28 04:50:49,269:vLLMHttpServer, replica_rank: 0, master address: 10.144.201.219, master port: 38905, data parallel master port: 38093
�[36m(vLLMHttpServer pid=27028)�[0m INFO:2025-10-28 04:50:49,273:override_generation_config: {'temperature': 0.6, 'top_k': -1, 'top_p': 1, 'repetition_penalty': 1.0, 'max_new_tokens': 2048}
�[36m(vLLMHttpServer pid=27028)�[0m INFO:2025-10-28 04:50:49,308:replica_rank=0, node_rank=0, nnodes=1, get worker zmq addresses: ['ipc:///tmp/verl_vllm_zmq_23757_root.ipc', 'ipc:///tmp/verl_vllm_zmq_23758_root.ipc', 'ipc:///tmp/verl_vllm_zmq_23759_root.ipc', 'ipc:///tmp/verl_vllm_zmq_23760_root.ipc', 'ipc:///tmp/verl_vllm_zmq_23761_root.ipc', 'ipc:///tmp/verl_vllm_zmq_23762_root.ipc', 'ipc:///tmp/verl_vllm_zmq_23763_root.ipc', 'ipc:///tmp/verl_vllm_zmq_23764_root.ipc']
�[36m(vLLMHttpServer pid=1793, ip=10.144.204.96)�[0m `torch_dtype` is deprecated! Use `dtype` instead!
�[36m(vLLMHttpServer pid=27028)�[0m `torch_dtype` is deprecated! Use `dtype` instead!

Furthermore, my enviroment is:

torch==2.8.0 
vllm==0.11.0
verl==0.6.0.dev
rllm==0.2.0

[huaiyizhao]

@nancyjlau cu128+torch2.8.0 is compatible with flash-attn 2.7.4.post1 in my env.
Check out volcengine/verl#3906. volcengine/verl#3934.

Btw, which sglang version are you using? I encontered some memory leak problem with sglang