I realized the IOMMU mapping is done with dma_alloc_ or dma_map_.. It's so basic (I have read https://www.kernel.org/doc/Documentation/DMA-API-HOWTO.txt ) but I forgot. Thanks! Chan Kim From: ckim@etri.re.kr <ckim@etri.re.kr> Sent: Wednesday, September 29, 2021 4:15 PM To: kernelnewbies@kernelnewbies.org Subject: does dma_alloc_coherent setup iommu page table? Hello all, When the driver calls dma_alloc_coherent for a device, and if the device uses iommu, is the table entry for the iommu setup for the dma_handle? Seeing the struct device has something related to iommu, I guess so.. Any help appreciated. Thanks! Chan Kim