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I'd rather we move forward with that then try to patch up this. > Support is gated behind CONFIG_IOMMU_IO_PGTABLE_CONTIG_HINT, which > provides a compile-time opt-out for hardware affected by SMMU errata > related to the contiguous bit. I reviewed the errata and didn't find any related to contig that required disabling contig, the driver was OK with the ones I found.. Did you find something specific? > On the unmapping side, the CONT bit is cleared from all PTEs in the > affected contiguous group before any individual entry is invalidated, > following the Break-Before-Make requirement of the architecture. BBM means you make it non-present and flush, it doesn't mean you clear CONT, this is wrong.. Jason