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Reed" To: "Peter Xu" Cc: "James Houghton" , "Andrew Morton" , linux-mm@kvack.org, "Axel Rasmussen" MIME-Version: 1.0 Content-Type: text/plain;charset=UTF-8 Content-Transfer-Encoding: quoted-printable Importance: Normal X-Priority: 3 (Normal) X-Type: plain In-Reply-To: References: <1757967196.153116687@apps.rackspace.com> <1757977128.137610687@apps.rackspace.com> <1758037938.96199037@apps.rackspace.com> X-Client-IP: 209.6.168.128 Message-ID: <1758043654.112619688@apps.rackspace.com> X-Mailer: webmail/19.0.28-RC X-Classification-ID: 0c2732c6-5237-44b2-a605-baad3a56a91a-1-1 X-Rspamd-Queue-Id: F3B274000D X-Stat-Signature: 76uz5i7o7uyeo1qbpdf413t4wox79jc6 X-Rspam-User: X-Rspamd-Server: rspam09 X-HE-Tag: 1758043668-606711 X-HE-Meta: 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 JKx4frzV bfQlH5NTvZEkOvFbaSizuwZL0WEud9N28UN/a7Cl3S7+K1hrPTuhTfkjbE0eDbgIxO7Z+mb1C9E/QWBA8tlB6hFhf7NlxndnjA7npJbkUpz/IyzZ8k/Qv7hClUdJhF5c7PzL0ThuEFtfIA4/jcCPOFrcvAt035HErPObx 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: Than -=0A=0AJust to clarify - =0ALooking at the man page for UFFDIO_API, th= ere are two "feature bits" that indicate cases where "minor" handling is no= w supported, and can be enabled.=0AUFFD_FEATURE_MINOR_HUGETLBFS and UFFD_FE= ATURE_MINOR_SHMEM =0AIn my reading of the documents, these seem to imply th= at before they were added as new features, that MAP_PRIVATE|MAP_ANONYMOUS m= appings were supported, and that the "new" additions to the MINOR mode were= just for HUGETLBFS and MAP_SHARED cases.=0A=0AIt seems odd that anonymous = page faults and COW would not be handled, given that context.=0A=0AAnyway, = that's unclear in any of the documentation. This just adds to my last respo= nse where I explain my use case.=0A