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I see what you mean now.. How does a DMA fault raise an SError? As I gave an example to Robin if the unhandled failure escalates into RAS emergency unplugging CXL memory then the system is going to explode when kdump touches that CXL memory as part of the dumping. It is not quite so simple that a DMA abort is triggering SError. I don't know exactly the sequence of events that lead up to the kdump kernel crashing (I imagine it is hard to debug that one), but it is something related to the new kernel not participating in the RAS and the RAS flow escalating to something fatal. Jason