[CI Bugfix] Fix failing test_invalid_env

[mgoin]

Purpose

The Kernels Attention Test job didn't run when #24761 landed

https://buildkite.com/vllm/ci/builds/31128/steps/canvas?jid=019957f9-c996-474a-8f31-03ce4d94f5f5

[2025-09-17T15:02:08Z] FAILED kernels/attention/test_attention_selector.py::test_invalid_env[True] - assert "Invalid attention backend: 'INVALID'" in "Invalid value 'INVALID' for VLLM_ATTENTION_BACKEND. Valid options: ['FLASH_ATTN', 'FLASH_ATTN_VLLM_V1', 'TRITON_ATTN_VLLM_V1', 'XFORMERS', 'ROCM_FLASH', 'ROCM_AITER_MLA', 'ROCM_AITER_MLA_VLLM_V1', 'ROCM_AITER_FA', 'TORCH_SDPA', 'TORCH_SDPA_VLLM_V1', 'FLASHINFER', 'FLASHINFER_VLLM_V1', 'FLASHINFER_MLA', 'TRITON_MLA', 'TRITON_MLA_VLLM_V1', 'CUTLASS_MLA', 'FLASHMLA', 'FLASHMLA_VLLM_V1', 'FLASH_ATTN_MLA', 'PALLAS', 'PALLAS_VLLM_V1', 'IPEX', 'DUAL_CHUNK_FLASH_ATTN', 'DIFFERENTIAL_FLASH_ATTN', 'NO_ATTENTION', 'FLEX_ATTENTION', 'TREE_ATTN', 'XFORMERS_VLLM_V1']."
[2025-09-17T15:02:08Z]  +  where "Invalid value 'INVALID' for VLLM_ATTENTION_BACKEND. Valid options: ['FLASH_ATTN', 'FLASH_ATTN_VLLM_V1', 'TRITON_ATTN_VLLM_V1', 'XFORMERS', 'ROCM_FLASH', 'ROCM_AITER_MLA', 'ROCM_AITER_MLA_VLLM_V1', 'ROCM_AITER_FA', 'TORCH_SDPA', 'TORCH_SDPA_VLLM_V1', 'FLASHINFER', 'FLASHINFER_VLLM_V1', 'FLASHINFER_MLA', 'TRITON_MLA', 'TRITON_MLA_VLLM_V1', 'CUTLASS_MLA', 'FLASHMLA', 'FLASHMLA_VLLM_V1', 'FLASH_ATTN_MLA', 'PALLAS', 'PALLAS_VLLM_V1', 'IPEX', 'DUAL_CHUNK_FLASH_ATTN', 'DIFFERENTIAL_FLASH_ATTN', 'NO_ATTENTION', 'FLEX_ATTENTION', 'TREE_ATTN', 'XFORMERS_VLLM_V1']." = str(ValueError("Invalid value 'INVALID' for VLLM_ATTENTION_BACKEND. Valid options: ['FLASH_ATTN', 'FLASH_ATTN_VLLM_V1', 'TRITON_ATTN_VLLM_V1', 'XFORMERS', 'ROCM_FLASH', 'ROCM_AITER_MLA', 'ROCM_AITER_MLA_VLLM_V1', 'ROCM_AITER_FA', 'TORCH_SDPA', 'TORCH_SDPA_VLLM_V1', 'FLASHINFER', 'FLASHINFER_VLLM_V1', 'FLASHINFER_MLA', 'TRITON_MLA', 'TRITON_MLA_VLLM_V1', 'CUTLASS_MLA', 'FLASHMLA', 'FLASHMLA_VLLM_V1', 'FLASH_ATTN_MLA', 'PALLAS', 'PALLAS_VLLM_V1', 'IPEX', 'DUAL_CHUNK_FLASH_ATTN', 'DIFFERENTIAL_FLASH_ATTN', 'NO_ATTENTION', 'FLEX_ATTENTION', 'TREE_ATTN', 'XFORMERS_VLLM_V1']."))
[2025-09-17T15:02:08Z]  +    where ValueError("Invalid value 'INVALID' for VLLM_ATTENTION_BACKEND. Valid options: ['FLASH_ATTN', 'FLASH_ATTN_VLLM_V1', 'TRITON_ATTN_VLLM_V1', 'XFORMERS', 'ROCM_FLASH', 'ROCM_AITER_MLA', 'ROCM_AITER_MLA_VLLM_V1', 'ROCM_AITER_FA', 'TORCH_SDPA', 'TORCH_SDPA_VLLM_V1', 'FLASHINFER', 'FLASHINFER_VLLM_V1', 'FLASHINFER_MLA', 'TRITON_MLA', 'TRITON_MLA_VLLM_V1', 'CUTLASS_MLA', 'FLASHMLA', 'FLASHMLA_VLLM_V1', 'FLASH_ATTN_MLA', 'PALLAS', 'PALLAS_VLLM_V1', 'IPEX', 'DUAL_CHUNK_FLASH_ATTN', 'DIFFERENTIAL_FLASH_ATTN', 'NO_ATTENTION', 'FLEX_ATTENTION', 'TREE_ATTN', 'XFORMERS_VLLM_V1'].") = <ExceptionInfo ValueError("Invalid value 'INVALID' for VLLM_ATTENTION_BACKEND. Valid options: ['FLASH_ATTN', 'FLASH_ATTN_VLLM_V1', 'T...UAL_CHUNK_FLASH_ATTN', 'DIFFERENTIAL_FLASH_ATTN', 'NO_ATTENTION', 'FLEX_ATTENTION', 'TREE_ATTN', 'XFORMERS_VLLM_V1'].") tblen=5>.value

Test Plan

Test Result

Tested locally

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[gemini-code-assist]

Code Review

This pull request is a CI bugfix that updates an assertion in test_invalid_env to match a changed error message. The test verifies that setting an invalid attention backend via an environment variable raises a ValueError. The change updates the expected error message substring from "Invalid attention backend: 'INVALID'" to "Invalid value 'INVALID'". This change appears to be correct for the purpose of fixing the failing test. The new error message is less descriptive, which could be a minor regression in user experience, but the change in the test itself is sound. I did not find any issues with high or critical severity in this change.

[mgoin]

Force merging to fix CI. Tested locally and precommit passes