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Once [1] is accepted > > > this may look redundant, but I still see the benefit in having it. > > > > What would be the benefit if [1] is accepted? > > Just another mechanism for verification, and pretty cheap one. > I would dare to say [1] does not rule out an invalid access completely. Ok, maybe we should revisit this when we know how the solution for page table accesses will be. Then hopefully it should be quite obvious if this additional code is helpful or not.