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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: CB7F04000D X-Stat-Signature: yin6t17qoohktounm7ktmm5hcugtozuy X-Rspam-User: X-HE-Tag: 1768989634-451107 X-HE-Meta: U2FsdGVkX1+sgAFYBTfZVPUznPghyYTe2F5l47Rvmj8KW/q4RD36hibf4GHj4txhgz5uyFC1+ov5cR0HP2DO9EMyQm1lAuGaaFYqnVnCpgLry87Br6xS3ixcg4VQVwc9WvpXMkzVzeIeTTS7FOckYNJ0XljpqwiHyl1Oq75mnGiL0+4NHnpNfy9mfofr/d12ajbMANTULnGDLq6gl8wj5TXRYHxkE7JxZHPujwwelF9BXtt7HcI7g0YaGRLf7tmFpNkmSQ4MlSZEF9DtQzQBViXGrQaeszIkBl8prrBvoqmkNzhMnKZ0FVOqh0MfGgGcqd8R9seXwy3l0rXYjhMU8KVOvnz6dTXTYhCc/7pcnBqv+tsEAEKH11pJxgPeL2GgZpRUVMGXBkV2yPf//SdA8gV2bttUiermUFrkTLHYu+Aj8lP/OcYMI5ewdYLYmB9ZCJz1/JMzsHAO04TjCmSWZfPaCfCWs9drhQXWLB9tPG79gm4Z+7yu20/kE97Rhr8OkBkoTdTJdRm/io7K4L3711ONJMhWJ4MIPaHc7K6V9D7oJtzhjHKpp4LxDADW+kkg3VXnMlyLyb4QCLUngoTBnNOm5M9aiTgvOumJeDLTK7d/zOxPt6wa+vME02LBLTbYdZfaf7kiodC761Aiu8lkVnJGrMZKj7FCLc3I5ROFQAiSveaG6Y4wPDJVxMgdIRDI9YQvQzLucrc2IaG3MmpF2X4TCQNndq9Zib/9TjcLdCf+gzdmgPa5OMgc5utwmhacghCRosDq36RyrGHVf0UAtMOoNt3/em/qt/1H18RzqeGcIxzdVQuB1Thm7NL+PkyaITKiB5mkt6k9+zACrQu6zTurBv8AmmyXesyNx4Dv/F/HhqGADAyU4qfgoNAoUIxsyQxAvs7xHVOj0ewhHm3NYDNzx3DJnDANBWchLIMoKEn7+sAsLo7IwTBWamVzNiTFh9GsW1449NaDTOWJVvM Y6bUv9u0 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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, Jan 20, 2026 at 07:50:32AM -0500, Jeff Layton wrote: > > > and it DOES provide stable filehandles. > > > > Across reboot? Not really. > > It's quite possible that we may end up with the same "id" numbers in > cgroupfs on a new incarnation of the filesystem after a reboot. The > files in there are not the same ones as the ones before, but their > filehandles may match because kernfs doesn't factor in an i_generation > number. > > Could we fix it by adding a random i_generation value or something? > Possibly, but there really isn't a good use-case that I can see for > allowing cgroupfs to be exported via nfsd. Best to disallow it until > someone comes up with one. Yeah. And I'm pretty sure everyone here will push back hard on any such use case.