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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.2 (3.60.2-1.fc44) MIME-Version: 1.0 X-Stat-Signature: uufj3p7t5x89bj74edc5g5dsin79n5dk X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: A5297180004 X-Rspam-User: X-HE-Tag: 1787969488-285981 X-HE-Meta: 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 Srz724Of EDRGNS+5yObZbbgHOPmYhFjwHxDN3x5KqByeJ4sMVZUkyPo4BhQ/8wowrm8QmuCTv9mayDDAbpgE30c98h2LiCVRIfJJaIC2/yl3IozibaAQ/XkMJpP57OqpSFOC+7x49Q+6bvxm1zMXIIidkWkSH53Kk7/lLVIz8MuAH4BSRU6JrSBFaq98WHuaPmFae6g8HqnwSEMA3JjJnxomCgZb1e0AtBXITUdBrhVt9mtv8vvWO1mCey2c6U7wkRqTnefCNTpOiHZEa3u/utJselGL0h3+zY4I3HK3FHyziNqbZH5Y3nCktgHeVkNR2U59s0o1bGjPK1OhqWlobPCEbSipnfZ+8L0bMk0zdGgdUVO0EejNIcm1mOEpB0W4AOiIKwVlAj37P Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 2026-08-28 at 16:47 -0700, Suren Baghdasaryan wrote: > On Mon, Aug 10, 2026 at 8:07=E2=80=AFPM Rik van Riel > wrote: > >=20 > >=20 > > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 /* > > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 * We only care about a= non pages in can_follow_write_pte(). > > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 */ > > -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if ((flags & FOLL_WRITE) && > > -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 !can_foll= ow_write_pte(pte, page, vma, flags)) { > > -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0 ret =3D 0; > > -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0 goto out; > > -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 } > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if ((flags & FOLL_WRITE) && !can_= follow_write_pte(pte, > > page, vma, flags)) > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0 return 0; >=20 > Before refactoring in the above case we would "goto out" and > no_page_table() would not be called even if pte_none(pte). Now I > think > you will call it if pte_none(pte). I'm not sure if this does not > matter but this seems like a functional change. Good catch, now we may end up calling no_page_table() on a VMA where we are not allowed to write, for a FOLL_WRITE access, while before we did not. That might turn 0 into -EFAULT in some corner cases. I don't know if we can actually hit any of those corner cases, or whether they matter in practice, but the fix seems easy enough, so I'll fix it for v4. --=20 All Rights Reversed.