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> > + if (pmd_is_device_private_entry(orig_pmd)) > + goto out; > + > if (unlikely(!pmd_present(orig_pmd))) { > VM_BUG_ON(thp_migration_supported() && > !pmd_is_migration_entry(orig_pmd)); > The change makes sense, I spent some time thinking if we should make madvise pmd free work for THP PMD entries, but that should be a separate patchset, it is much more complex and involved. Reviewed-by: Balbir Singh