Problem

All 189 tests in inductor/test_cutlass_backend.py fail on RHEL 9.6 with H200 GPU.

Root Cause

CUTLASS library (NVIDIA CUDA Templates for Linear Algebra Subroutines) is not properly installed or configured in the RHEL build environment.

Impact

• Tests failing: ~189
• Severity: Low - CUTLASS is an optional optimization library
• Production impact: None - Core PyTorch functionality works without CUTLASS
• Pass rate impact: Accounts for 88% of all failures (189/215)

Current Workaround

Tests excluded in workflow configuration

Acceptance Criteria

• [ ] CUTLASS library installed in RHEL Docker image
• [ ] PyTorch configured to find CUTLASS installation
• [ ] All 189 CUTLASS backend tests pass on RHEL H200
• [ ] Tests remain excluded until fix is verified

References

• Workflow run: https://github.com/subinz1/pytorch/actions/runs/20745368086
• Documentation: 5_SHARD_FAILURE_SUMMARY.md