On Mon, May 12, 2025 at 06:52:31PM +0100, Matthew Wilcox wrote: > > > > Feel free to submit patches that deletes the existing code if you want > > it removed from the documentation. > > Who sneaked that in when? The ACPI and EFI folks when they allowed for CXL memory to be marked EFI_CONVENTIONAL_MEMORY - which means Linux can't actually differentiate between DRAM and CXL during __init and brings it online in the page allocator as SystemRAM in ZONE_NORMAL (attached to the NUMA node that maps to the Proximity Domain in the SRAT). Not sure there's anything you can do about that. And for DAX: 09d09e04d2 (cxl/dax: Create dax devices for CXL RAM regions) Which allows for EFI_MEMORY_SP / Soft Reserved CXL regions to be brought up as a DAX devices (which can be bound to SystemRAM via DAX kmem). Wasn't much sneaking going on here - DAX kmem has been around and hacked on since 2019, and probably some years before that. ~Gregory
