IOMMUFD is the kernel's user-facing interface for managing IO Memory Management Units, the hardware that translates and isolates DMA from devices. It lets userspace tools (notably VFIO and modern virtualization stacks) build and share IOMMU page tables to safely pass devices through to virtual machines or user processes.
This is not actually a hardware driver; it is core kernel infrastructure that sits above the per-vendor IOMMU drivers and exposes a unified file-descriptor API to userspace. It belongs firmly in the tree as foundational plumbing for device passthrough and virtualization, so the keep/remove question does not apply.
repository signals
18files
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302commits, 5y
+16,903 / −3,136lines added / removed, 5y
30authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 302 total · active in 37/61 months
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codex reasoning notes (technical)
Not a driver directory: contains the iommufd IOMMU userspace/core subsystem glue, not a hardware-bound device driver for a specific chipset or product family.