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If you prefer, I >> can drop the Fixes tag and only mention d8ef5e311d7b in the changelog, as >> there is nothing to backport. > > I mean, it seems like a bug to me? If there's no harm in backporting it I think you > should add Cc: stable@vger.kernel.org in that case actually. Nobody ever called this helper till the patch "mm/huge_memory: copy file THPs at fork like copy_present_ptes() does" in the current series, so there is no actual bug to fix in stables, so may be not to add extra work to stable trees maintainers? The other question is: what to do with the actual bug this series is addressed to. i don't think the significant rewrite of PMD handling is a good patch for stable, so may be we'll need to create a minimal fix like my 1st version to fix the existing problem - especially for stable trees. Or may be not to fix stables at all. But let's first finish with the proper fix/rewrite. One problem a time to solve. -- Cheers, Konstantin