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charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: EC2CC4001D X-Stat-Signature: m9nn81pgmsxycx5o8sr9kz3q3uur3bh9 X-HE-Tag: 1689761884-174205 X-HE-Meta: U2FsdGVkX1/Gg/Xn/PXbLlXfnk93LO2vKLEw6qzBJuuRWiyTOZbyllkkyPOPoLg6juHvq0ogwKQEkt8b1lYlSBK+k2DtBwa39bOVENt/V4rTy+gvlHbFeSuQmns74VzVOFAtFMi0r6nGeBZJ8rAJeZXm3Vh0xy87wx6UvfojqNbxpCZO8XVD52asyHqa4fuiS9Be4gXSB2kzITEJcR2tfpI0yl8Y/dZg34aLjDRl3yaYMIMwonceYtcj50jTAPvuhtobifywGogoP83EC5KFX//1rPD6o2MRJNZjJehywFndO2MmCJnNc9/2vIaM6vg40q16YaMSv4ayfx9OQm/2veUSltG+s98PigToa1Is+pUIq5fjrHQ47VSLPIbz8eXzoRrXr5P/0QB/uGQJxb/S52bPYCrAvGISbtGS9yBqVPuLRK8ZqHfBz8/q4La3aTHOUY/gPClYx5UOSlzmr0nEr0AzmDIPEOiSkMRIvLT5IXolNFMzfjG305OzrGJUP7kjAPXK9V1p4u2eiitETlTt57gD+k4HVOgxRzWUf9uYLZH/uPOFbdBzTylb37S7m2P32iTVY8belxJsxtzX4I8Zm+x32jZZm+zEKX8gp7dmRdsaVl0v0ZSNWCVCDeATIgJ2UuCbZYzF6SuRT6DjYxh/GzjM3ru5kpI6bUjlW7G89UYUTSV1342OREPFUcBYG7+7/KdEuVZY4KFoa7FZgKYUU7aE3mQlJNWj6VT0y9bCwsTjCgXr+e+8djqDSz8WdhsnDme4GnJM2fInSuMH5q6XpV2ag3yVsP/QgKIu5GrmZDXpZfIqzBw32mM/kiYYgt6+/e600fkkzF5OSYU4xE+GsewBX3Bcd5CJaaay7Gix9+Mz0ZcWmt4qd/ao51PmXkqxs42zpjwAi73iNZCRD97DggkUlFPd0hpaSW5kVZzdcDiBGO/84m2FFOLgh9KG5p1Cgf03LQ+4TlTBMMBdjP5 tdI/0Pk+ qbQdPV6SmyG2jlu4cLON+s3+FADTw7yne2yM5uRFCMyGwuJ5KeTCdP5yoF7D4SnEXK4yuGE7LrjR0tWhGy0JdgbgPmXmP6BAU9xAlmTqRxdx2WOYVWk6YY6u0ozovBiTYrfVRmxIOpNCaD+I6H7ZrHRDlfcmj/WrLgW7BD/Fk3+w7SggNb7KA2d+fJ+s8bLt70HekJb2S8wlyiyxJF89lsi4LvoJs69TFXsCKoY9OlecSLzEKDNq90+I8/A== 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 Thu, 29 Jun 2023 at 17:56, David Howells wrote: > > Splicing data from, say, a file into a pipe currently leaves the source > pages in the pipe after splice() returns - but this means that those pages > can be subsequently modified by shared-writable mmap(), write(), > fallocate(), etc. before they're consumed. What is this trying to fix? The above behavior is well known, so it's not likely to be a problem. Besides, removing spliced pages from the cache is basically guaranteed to result in a performance regression for any application using splice. Thanks, Miklos