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See http://www.infradead.org/rpr.html X-Stat-Signature: rh9ees9ktddtptkhbec98cp4os538irr X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 25CBB1C000F X-Rspam-User: X-HE-Tag: 1684316175-944753 X-HE-Meta: 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 hrRG8ynr 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 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 Wed, May 17, 2023 at 02:56:13PM +0530, Sumit Garg wrote: > Do you mean a pinned user-space page can be paged out automatically? No, pinned pages can't be paged out. But a short term pin implies it will be release after a short delay, and it is feasible for wait for the pin to go away. For a long term pin waiting is not an option, and anyone wanting to do something with the pinned page that requires it to not be pinned must simply give up. > Just FYI, the underlying use-case for TEE registered shared memory is > that the references to pinned pages are provided to TEE implementation > to operate upon. This can happen over multiple syscalls and we want > the pinned pages to be always in RAM as otherwise the physical > addresses may change if they are paged out in between. That's a very use clear case for a long term pin.