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Hi Mike, I like this. Some questions below: > +static struct platform_driver ramdax_driver = { > + .probe = ramdax_probe, > + .remove = ramdax_remove, > + .driver = { > + .name = "e820_pmem", > + .of_match_table = of_match_ptr(ramdax_of_matches), So this driver collides with both e820_pmem and of_pmem, but I think it would be useful to have both options (with/without labels) available and not require disabling both those other drivers at compile time. 'struct pci_device_id' has this useful "override_only" flag to require that the only driver that attaches is one that is explicitly requested (see pci_match_device()). Now, admittedly platform_match() is a bit more complicated in that it matches 3 different platform device id types, but I think the ability to opt-in to this turns this from a "cloud-host-provider-only" config option to something distro kernels can enable by default.