Multiple operations may use the same address, and identifiers can later be reused. Retain the request identity and apply the protocol/platform’s recovery policy before recycling tracking.

Common trap: Giving a generic fix without identifying the boundary and unmet obligation in this example.

LTSSM history, negotiated parameters and lane diagnostics describe training. Configuration requests/completions, resource assignments and firmware/OS logs describe enumeration. L0 at the expected width is useful evidence, not proof that the transaction path is fault-free; an undiscovered device can involve reset, endpoint responses, routing, permissions or software setup. Compare the first failing operation before assigning ownership.

Common trap: Treating the final link state or an enumeration log as proof of one owning layer.