IOMMUadmitted

IOMMUadmitted is a neologism used in some technical discussions to describe the state of a device or DMA channel that has been granted permission to perform direct memory access under the protection of an Input-Output Memory Management Unit (IOMMU). In this sense, an IOMMUadmitted device has its DMA requests translated and checked by the IOMMU and mapped into an I/O virtual address space within a defined protection domain.

The term is informal and not part of official standards. It is commonly encountered in virtualization, kernel development, and system administration conversations when discussing PCI devices, IOMMU groups, and device passthrough to virtual machines. It conveys that the device has passed the necessary checks and is operating under the IOMMU’s DMA isolation and address translation rules.

In practical terms, admitting a device typically involves enabling DMA remapping, associating the device with an IOMMU domain or group, and configuring the IOVA space so that DMA operations are translated and checked against access rights. The result is memory isolation for the device’s DMA traffic and, in virtualization scenarios, safe assignment of devices to guests without compromising host stability or security.

Limitations and caveats exist. Some devices may not be admit-able due to lack of IOMMU support, incompatible resource requirements, or complex inter-device relationships. Admission status can change with hot-plug events or virtualization reconfigurations, and enabling IOMMU can introduce performance overhead.

Because it is informal, the exact meaning of IOMMUadmitted can vary by context. Readers should rely on precise terms such as DMA remapping, IOMMU-enabled, or IOMMU group when documenting or implementing related functionality.