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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 3C6BE40012 X-Stat-Signature: fjqkeac15jyznxiuzyiudkecer36fi41 X-Rspam-User: X-HE-Tag: 1730262068-277574 X-HE-Meta: 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 4wCVuZMh 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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 Tue, Oct 29, 2024 at 08:01:16PM -0700, John Hubbard wrote: > A user-visible consequence has now appeared: user space can no longer > pin more than 2GB of memory anymore on x86_64. That's because, on a 4KB > PAGE_SIZE system, when user space tries to (indirectly, via a device > driver that calls pin_user_pages()) pin 2GB, this requires an allocation > of a folio pointers array of MAX_PAGE_ORDER size, which is the limit for > kmalloc(). Do you have a report whee someone tries to pin that much memor in a single call? What driver is this? Because it seems like a not very smart thing to do.