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See the "Maturity Map" [1] document for what the driver supports. [1]: http://lore.kernel.org/172005486862.2048248.6668794717827294862.stgit@dwillia2-xfh.jf.intel.com In terms of "plans", it is in the "patches welcome" state. While CXL PMEM was an early focus of the kernel enabling, no PMEM devices materialized in the market so focus moved elsewhere. > Including init GPF DVSEC, flush data to GPF domain, etc. One thing that guide does not cover is what should OS software do with a dirty shutdown failure. To my knowledge there is no specific plumbing for handling NVME device write-cache failures beyond: "hope filesystem logging and metadata checksums can recover a consistent filesystem". I do agree that the driver has a responsibility to set switch timeout values, but that is more an unfortunate complexity imposed by the spec. Just set the max and rely on devices to minimize GPF response times to avoid the worst case wait times that those timeouts imply. In any event, enabling that is "up for grabs."