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Did you find something specific? > > Arm MMU-700 is affected by erratum 3777127 ("Under invalidation in TBU > possible when using contiguous page table entries"). That looks like the same as the one I found 3673557 for Neoverse MMU S3 > However, if we disallow partial unmaps of groups of adjacent > translation table entries, we implicitly apply the workaround > ("Ensure that contiguous page tables are removed using a single > range invalidation. Arm recommends using range invalidations to > remove contiguous entries anyway for performance reasons.") Right, that was my conclusion as well. SMMUs with this errata should not enable BBM level 3 support which is the only thing that can trigger a partial unmap of a contig block. My assumption was RIL is supported in all affected SMMUs since that is the recommended workaround.. Jason