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From: Lance Yang In-Reply-To: <6f448506-677f-4e0c-aa9c-d5da061e57ee@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Stat-Signature: ewb1i19cfnd9rprz5kwxqrpho56hcwni X-Rspamd-Queue-Id: 82DFA4000F X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1760452695-638715 X-HE-Meta: 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 QpRwGwDh taEC8kEPOyYvjiXwAidg28hOxufPfr/eRzNKLCn+W/FhaRKl/E731thI2CN5gyKljK1JuBlahDx/tbXW+Hb8f2/REPvJs0FK1GLp+bXD4yzwrcRm86NKzFkB5/r9yyR8Ux2+Tty3Emi5ckIi9YjptPu8y/f8rzyUkhRu9d1A38IXAdtjzvbFnZyPzBQav1aTHOxrvKx4RPeSQRqOKuB3piqKOf/fQQcIolmYcpsNUjZ1czAmU5+uK63UcfjeT+Bb7pynAtz5sNorLVPMoLSm2VF8lPZ0IcBi+w+4zXvv1zOAkJD0v3Rq6x8VYrw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2025/10/14 22:32, David Hildenbrand wrote: > >> static inline int pte_protnone(pte_t pte) >> { >>     return (pte_flags(pte) & (_PAGE_PROTNONE | _PAGE_PRESENT)) >>         == _PAGE_PROTNONE; >> } >> >> static inline int pte_present(pte_t a) >> { >>     return pte_flags(a) & (_PAGE_PRESENT | _PAGE_PROTNONE); >> } >> ``` >> >> On x86, pte_present() returns true for a protnone pte. And I'd assume >> other archs behave similarly ... > > Applies to all architecture. prot-none entries must be present, > otherwise we'd have a lot of other issues :) Thanks for confirming, David! That's good to know ;p So @Lorenzo, looks like we're good here on the protnone front. Does that clear up your concern?