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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 6D5EA1C0003 X-Stat-Signature: nf775foyuqs3e7md8uif3rgw6sirywx6 X-Rspam-User: X-HE-Tag: 1768809413-946337 X-HE-Meta: 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 owr749wU 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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 Fri, Jan 16, 2026 at 08:09:16AM +1100, Dave Chinner wrote: > > I think we can be a lot more precise about the guarantee: The file > > handle does not change for the life of the inode it represents. It > > > > File handles most definitely change over the life of a /physical/ > inode. Unlinking a file does not require ending the life of the > physical object that provides the persistent data store for the > file. > i.e. a free inode is still an -allocated, indexed inode- in the > filesystem, and until we physically remove it from the filesystem > the inode life cycle has not ended. For other file systems like ext4 that have statically allocated inodes that is even more so the case. > IOWs, the physical (persistent) inode lifetime can span the lifetime > of -many- files. However, the filesystem guarantees that the handle > generated for that inode is different for each file it represents > over the whole inode life time. > > Hence I think that file handle stability/persistence needs to be > defined in terms of -file lifetimes-, not the lifetimes of the > filesystem objects implement the file's persistent data store. Agreed, although I bet that is what most folks think of for the inode - not a physical place on disk, but an object that gets invalidated on the last close after unlink. Either way, that rules do need to be written down clearly.