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Roll back target > mappings on error. This still recovers physical addresses > internally. Absolutely not. You cannot recover the phys_addr's from a DMABUF expoter by using iommu_iova_to_phys(). Christian is adamant that drivers must not use physical addresses, and I will not agree to any hacks like this to try to end-run around his prohibition by abusing iommu subsystem. NAKed-by: Jason Gunthorpe If you want to keep the domain in the rockchip driver you have to fix DMABUF to allow an importer to use an iommu domain safely. It *must not* be done with a scatterlist interface, sorry, I know that is alot of work but Alistair is going to take a serious stab at it. Many users want this, not just rockchip. So help with the work to allow iommufd to do this and you will get it for free. 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org On Fri, Oct 09, 2026 at 02:21:13AM +0200, Karl Mehltretter wrote: > DMA-BUF attachments provide DMA addresses, not CPU-side pages. > iommu_map_sgtable() needs those pages, so private-domain importers such > as Rockchip cannot use it with strict DMABUF_DEBUG. > > Add an iommu-dma helper to map a live attachment into another domain by > translating through the device's default DMA domain. Roll back target > mappings on error. This still recovers physical addresses > internally. Absolutely not. You cannot recover the phys_addr's from a DMABUF expoter by using iommu_iova_to_phys(). Christian is adamant that drivers must not use physical addresses, and I will not agree to any hacks like this to try to end-run around his prohibition by abusing iommu subsystem. NAKed-by: Jason Gunthorpe If you want to keep the domain in the rockchip driver you have to fix DMABUF to allow an importer to use an iommu domain safely. It *must not* be done with a scatterlist interface, sorry, I know that is alot of work but Alistair is going to take a serious stab at it. Many users want this, not just rockchip. So help with the work to allow iommufd to do this and you will get it for free. Jason _______________________________________________ Linux-rockchip mailing list Linux-rockchip@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-rockchip