ACPI NFIT NVDIMM persistent memory
Support for persistent (non-volatile) DIMMs described to the operating system through the ACPI NFIT table, most notably Intel Optane Persistent Memory modules that plugged into DDR4 memory slots on Xeon servers from roughly 2019 through 2022. It exposes those modules to Linux as byte-addressable persistent memory regions and block devices via the libnvdimm framework.
recommendation
Worth keeping but worth flagging as a legacy niche. The physical hardware it was built for, mainly Intel Optane Persistent Memory, was discontinued in January 2023 with CXL pitched as its successor, so new deployments are rare. However, upstream patches were still landing in 2025 and 2026, fixes are being backported to stable, and QEMU continues to expose NFIT to virtual machines, so existing servers and VM testbeds still depend on it.
repository signals
sources
- lore.kernel.org
Upstream NFIT work was still landing in 2026, indicating the driver is maintained rather than abandoned.
- lore.kernel.org
NFIT fixes were still being backported to stable in late 2025, showing ongoing real-world maintenance value.
- intel.com
Intel states it canceled future Optane Persistent Memory products effective January 31, 2023 and points to CXL as the future direction, so NFIT-backed PMem is no longer a growth market.
- qemu.org
QEMU still documents ACPI/NFIT-based NVDIMM support, so NFIT remains relevant for virtualized and test environments even as physical hardware declines.
codex reasoning notes (technical)
Real driver directory: Kconfig says it probes ACPI NFIT platforms and registers a libnvdimm tree. `lore_file_timeline` MCP on `drivers/acpi/nfit/core.c` showed recent 2025-2026 patches and stable backports; no removal signal surfaced from the fast lore pass. Intel support article was obtained via web search and shows future Optane PMem was canceled effective 2023-01-31, with CXL positioned as the successor direction; QEMU doc from web search shows continuing NFIT use in VM contexts. Net: physical NFIT hardware is legacy and likely no longer sold new in 2025, but the driver still has active upstream maintenance and some ongoing deployment, so keep it with legacy/low-growth annotation rather than deprecate/remove.