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Howlett" , "Paul E. McKenney" , Suren Baghdasaryan Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: tf5x4czbjunigmdyfe13bbi65b99czs1 X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: B400C140005 X-Rspam-User: X-HE-Tag: 1684556570-149173 X-HE-Meta: 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 Kz5vvAxc mJP7yvIrlUe4paZ7CkxVo5qKKm63XEoh5XlI1aOes9k8uBFLbldz2s+N7l4/PuQeL/42QOZ7vapHD/XzLZwGWzXop2VQupWbNtkpHInZaaLMLWT+7v36QRS5GO2gmqhZ7EfWiU3z2AqZ9j8DevU5LBQGbfXapEqGL0dLSqnQjH7c3OEH5rgoXGtMY6lyho+24WN5mus6x+TuH6xin5kCeITpcwtO4RfWM5I/axh41wfZoNfApyMIlEi38msxlEGcDiXjMy0j0pBHx3aAS75hGjie9IrnwFU/71cysBOBaC4Iz2F3KKvSXZUzF297Z/7ik/TJ4u+v+rQEpZqKsVEQYmNUaUiTAGWZUnbbp++tTy91VpHjXs1IXCgORwkX5ChkCccYBC2aE52v2MTs= 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: On Sat, May 20, 2023 at 12:14=E2=80=AFAM Joel Fernandes wrote: > > On Sat, May 20, 2023 at 12:01=E2=80=AFAM Linus Torvalds > wrote: > > > > On Fri, May 19, 2023 at 8:57=E2=80=AFPM Joel Fernandes wrote: > > > > > > I also realize that I don't really need to check whether the masked > > > source address falls under a VMA neighboring to that of the source's. > > > > I don't think that's true. > > > > You can't start randomly moving other source vma's that may have other = contents. > > If the beginning part of the PMD is not mapped at the destination, I > thought maybe a whole PMD could be moved to it. But I guess not > because we don't want those contents to be accessible. So then in that > case we have to forbid the optimization for all intra-VMA moves except > those involving the stack. I will think more about it. Duh, we can't move crap from the source like that also because it has real data. I think I got confused between "moving" and "copying". I feel silly, maybe it is time to go to sleep and live to fight another day. - Joel