skip gdn core_attn_out check for 8k len due to random numeric error

[YangQun1]

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• The test plan, such as providing test command.
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[Copilot]

Pull request overview

Updates the GDN attention kernel test to skip validation of core_attn_out for the 8192-token case due to intermittent numeric mismatches, aiming to reduce flaky failures in the XPU test suite.

Changes:

• Broadens the 8k-length skip condition for core_attn_out validation in test_gdn_attention.

Comments suppressed due to low confidence (1)

tests/gdn_attn/test_gdn_attn.py:412

• pytest.skip(...) here skips the remainder of the test, not just the core_attn_out assertion (it also prevents the later conv_state/ssm_state checks from running). If the intent is only to bypass validating core_attn_out for the 8192-token case, prefer conditionally skipping just that assertion (e.g., guard the assert_close(core_attn_out, ...) with if num_actual_tokens != 8192:) so other validations still execute.

    if num_actual_tokens == 8192:
        pytest.skip("FIXME, skip core_attn_out test because of random error")

    torch.testing.assert_close(core_attn_out,
                               ref_core_attn_out,

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[Copilot]

This change broadens the skip condition from ssm_state_is_fp32 and num_actual_tokens == 8192 to num_actual_tokens == 8192, which significantly reduces coverage for the 8k-token case across all dtypes/state configurations. If the mismatch is only present for specific configurations, keep the skip as narrow as possible; otherwise add a brief note (and ideally a tracking issue/bug ID) explaining why the 8k case is universally skipped.

[Copilot]

The skip message is very generic ("random error") and doesn’t provide enough context to act on. Consider including the failing symptom (e.g., max diff / which output diverges), the platform (PVC/XPU), and a link to a tracking issue so this doesn’t become a permanent skip.

[Copilot]

The PR description template is still unfilled (Purpose/Test Plan/Test Result). Please add at least a short purpose statement and a test command/result, especially since this change relaxes test validation for the 8k-token path.

[jikunshang]

please help root cause later, thanks!

[YangQun1]

please help root cause later, thanks!

sure