CVE-2025-38216 is a high-severity vulnerability in the Linux kernel's iommu/vt-d subsystem. A recent change to context entry setup order for aliased PCI devices behind PCIe-to-PCI bridges caused regressions, notably breaking keyboard and touchpad functionality on some Apple MacBooks. The issue stems from a commit that altered the setup from a set-and-check to a clear-and-reset approach, which inadvertently introduced faults in DMA read access permissions. The vulnerability is addressed by restoring the previous context entry setup order.