Pcie Device - Remapping

That’s in action. It’s not a bug or random glitch. It’s a deliberate, critical feature of modern IOMMU (Input-Output Memory Management Unit) architecture and virtualization. What Actually Gets “Remapped”? There are three distinct layers of remapping:

PCIe Device Remapping: Why Your GPU Isn’t Where You Think It Is pcie device remapping

cat /sys/kernel/debug/iommu/intel/translation_table Or for AMD: That’s in action

This is the big one. A PCIe device can cache virtual-to-physical address translations. When a device issues a read/write, it uses an IO Virtual Address (IOVA) . The IOMMU behind the root port remaps that IOVA to a host physical address. From the device’s perspective, its memory window moved. From the CPU’s perspective, the device is now pointing to a different physical RAM location. pcie device remapping