Fix: Qwen2-VL training on video datasets

[hiyouga]

What does this PR do?

We should clone the leaf tensor before doing the in-place operation, otherwise it raises exception in training.

File "/site-packages/transformers/models/qwen2_vl/modeling_qwen2_vl.py", line 1589, in forward
    inputs_embeds[video_mask] = video_embeds
RuntimeError: a leaf Variable that requires grad is being used in an in-place operation.

Similar to

transformers/src/transformers/models/qwen2_vl/modeling_qwen2_vl.py

Lines 1578 to 1584 in 9230d78

	if pixel_values is not None:
	pixel_values = pixel_values.type(self.visual.get_dtype())
	image_embeds = self.visual(pixel_values, grid_thw=image_grid_thw).to(inputs_embeds.device)
	image_mask = input_ids == self.config.image_token_id
	if self.training:
	inputs_embeds = inputs_embeds.clone()
	inputs_embeds[image_mask] = image_embeds

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• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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• Did you write any new necessary tests?

Who can review?

@ArthurZucker @zucchini-nlp @simonJJJ

[zucchini-nlp]

Oh yeah, and this also prevents compile. Can we use torch.masked_scatter for consistency among VLMs and readability (w/o any if/else)

[hiyouga]

@zucchini-nlp We have updated the implementation, how about the new one?

[zucchini-nlp]

@hiyouga sorry, what do you mean by "the new one"?

[hiyouga]

@zucchini-nlp sorry, i say the latest commit in this PR 96286c3

[zucchini-nlp]

Thanks, looks good to me!

[HuggingFaceDocBuilderDev]

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[ArthurZucker]

NIce! Would want to add a test to make sure this works, but good to merge as well

[hiyouga]

@ArthurZucker Hi, I think this slow test case already covers this patch, it may require non-trivial effort to implement a test case for training I think.

transformers/tests/models/qwen2_vl/test_modeling_qwen2_vl.py

Lines 324 to 359 in e48e5f1

	@slow
	def test_small_model_integration_test(self):
	model = Qwen2VLForConditionalGeneration.from_pretrained(
	"Qwen/Qwen2-VL-7B-Instruct", torch_dtype="auto", device_map="auto"
	)
	text = self.processor.apply_chat_template(self.messages, tokenize=False, add_generation_prompt=True)
	inputs = self.processor(text=[text], images=[self.image], return_tensors="pt")
	expected_input_ids = [151644, 8948, 198, 2610, 525, 264, 10950, 17847, 13, 151645, 198, 151644, 872, 198, 151652, 151655, 151655] # fmt: skip
	assert expected_input_ids == inputs.input_ids[0].tolist()[:17]
	expected_pixel_slice = torch.tensor(
	[
	[0.8792, 0.8792, 0.9084],
	[1.1858, 1.1858, 1.2296],
	[1.2004, 1.2004, 1.2150],
	[1.4340, 1.4340, 1.4194],
	[1.3902, 1.4048, 1.4194],
	[1.5216, 1.5362, 1.5362],
	],
	dtype=torch.float32,
	device="cpu",
	)
	assert torch.allclose(expected_pixel_slice, inputs.pixel_values[:6, :3], atol=3e-3)
	# verify generation
	inputs = inputs.to(torch_device)
	output = model.generate(**inputs, max_new_tokens=30)
	EXPECTED_DECODED_TEXT = "system\nYou are a helpful assistant.\nuser\nWhat kind of dog is this?\nassistant\nThe dog in the picture appears to be a Labrador Retriever. Labradors are known for their friendly and intelligent nature, making them popular pets"
	self.assertEqual(
	self.processor.decode(output[0], skip_special_tokens=True),
	EXPECTED_DECODED_TEXT,
	)

[zucchini-nlp]

Imo the fullgraph compile tests should capture the test, but those are part of GenerationTester and Qwen2VL yet doesn't have it. For that we need generation tests with image + text + (optional video) inputs, will add those soon. Tracker here #33374

[ArthurZucker]

Okay all thanks ! Let's merge 🤗 We'll improve the ecosytem for video and related tests on the fly! 🚀