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See http://www.infradead.org/rpr.html X-Stat-Signature: xop47xr6i135kuf49notqm5xosk33kh6 X-Rspamd-Queue-Id: 0651E40006 X-Rspam-User: X-Rspamd-Server: rspam09 X-HE-Tag: 1741793107-820687 X-HE-Meta: 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 /8i29WEY 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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: List-Subscribe: List-Unsubscribe: On Wed, Mar 12, 2025 at 08:20:36AM -0700, Suren Baghdasaryan wrote: > > Direct I/O pages are not unmovable. They are temporarily pinned for > > the duration of the direct I/O. > > Yes but even temporarily pinned pages can cause CMA allocation > failure. My point is that if we know beforehand that the pages will be > pinned we could avoid using CMA and these failures would go away. Direct I/O (and other users of pin_user_pages) are designed to work on all anonymous and file backed pages, which is kinda the point. If you CMA user can't wait for the time of an I/O something is wrong with that caller and it really should not use CMA.