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Wearing only my upstream kernel development hat, the question for merging is "what is the end user visible impact of merging this?". As long as DCD remains in proof-of-concept mode then leave the code out of tree until it is ready to graduate past that point. Same held for HDM-D support which was an out-of-tree POC until Alejandro arrived with the SFC consumer. DCD is joined by HDM-DB (awaiting an endpoint) and CXL Error Isolation (awaiting a production consumer) as solutions that have time to validate that the ecosystem is indeed graduating to consume them. There was no "chicken-egg" paradox for the ecosystem to deliver base static-memory-expander CXL support. The ongoing failure to get productive engagement on just how ruthlessly simple the implementation could be and still meet planned usages continues to give the impression that Linux is way out in front of hardware here. Uncomfortably so.