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>>>>         *rw &= pmd_flags(*pmd) & _PAGE_RW; >>>>   >>>> -       return pte_offset_kernel(pmd, address); >>>> +       pte = pte_offset_kernel(pmd, address); >>>> +       if (pte_none(*pte)) >>>> +               return NULL; >>>> + >>>> +       return pte; >>> The other levels check for pXX_none() before adjusting *level. Not sure what >>> the >>> effect would be, but I think it should be the same behavior for all. >> >> If we are returning NULL, why should adjusting *level matter. > > Well, I think symmetry is enough of a reason, but actually it should be ok. > > I was looking at this diff compared to my working tree, but this tip commit Ditto for me. Thanks, Tom > (which is about that scenario) makes it set *level before checking none for all > of them: > https://lore.kernel.org/lkml/171871930159.10875.16081839197437299007.tip-bot2@tip-bot2/ > > So sorry, nevermind.