All > Alex (or anyone else) can you point to where IOVA addresses are generated? A case of RTFM perhaps (though a pointer to the code would still be appreciated). https://www.kernel.org/doc/Documentation/Intel-IOMMU.txt Some exceptions to IOVA ----------------------- Interrupt ranges are not address translated, (0xfee00000 - 0xfeefffff). The same is true for peer to peer transactions. Hence we reserve the address from PCI MMIO ranges so they are not allocated for IOVA addresses. Cheers Stephen