When the hardware can't make the guarantees, then software really can't do anything about it. There's really not any checks you can do, but modern hardware is getting the capabilities to try to prevent those kinds of issues with the IOMMU units, but operating system support is still hit or miss for most hardware and it won't prevent everything (just devices stomping on each-other with DMA). That's basically how the thunderbolt attacks have worked and the solutions to them.