On Wed, Jul 01, 2026 at 11:30:08AM +1000, Alistair Popple wrote: > Agree with most of the above and this seems the most likely explaination. ATS > doesn't change much here - most of our driver still goes via dma_map/unmap to > access host memory via an IOMMU IOVA so non-present entries there would be > fatal > at the IOMMU level. So even with ATS enabled a non-present DMA mapping should > still result in noisy IOMMU faults.
AFAIK, the iommu driver does not log ATS non-present replies, those are considered normal events. The device itself is the only source of reporting. Jason
