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charset=us-ascii Content-Disposition: inline In-Reply-To: <20260115-inspektion-kochbuch-505d8f94829e@brauner> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: D1B2FC000E X-Rspamd-Server: rspam06 X-Stat-Signature: xo1yxnp1gsu364eme5hq3gt6esdq38cq X-Rspam-User: X-HE-Tag: 1768466019-454684 X-HE-Meta: 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 wZFIR8t8 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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 Thu, Jan 15, 2026 at 09:14:06AM +0100, Christian Brauner wrote: > On Wed, Jan 14, 2026 at 10:42:48PM -0800, Christoph Hellwig wrote: > > On Wed, Jan 14, 2026 at 04:20:13PM +0100, Christian Brauner wrote: > > > > You're still think of it the wrong way. If we do have file systems > > > > that break the original exportfs semantics we need to fix that, and > > > > something like a "stable handles" flag will work well for that. But > > > > a totally arbitrary "is exportable" flag is total nonsense. > > > > > > File handles can legitimately be conceptualized independently of > > > exporting a filesystem. If we wanted to tear those concepts apart > > > implementation wise we could. > > > > > > It is complete nonsense to expect the kernel to support exporting any > > > arbitrary internal filesystem or to not support file handles at all. > > > > You are going even further down the path of entirely missing the point > > (or the two points by now). > > You're arguing for the sake of arguing imho. You're getting exactly what > we're all saying as evidenced by the last paragraph in your mail: it is > entirely what this whole thing is about. I can't even parse what you mean. And no, I hate these stupid arguments, and I have much better things to do than dragging this on. > > If a file systems meets all technical requirements of being nfsd > > exportable and the users asks for it, it is not our job to make an > > arbitrary policy decision to say no. > > This is an entirely irrelevant point because we're talking about > cgroupfs, nsfs, and pidfs. And they don't meet this criteria. cgroupfs > is a _local resource management filesystem_ why would we ever want to > support exporting it over the network. It allows to break the local > delegation model as I've explained. cgroupfs shows _local processes_. So > a server will see completely nonsensical PID identifiers listed in > cgroup files and it can fsck around with processes in a remote system. None of that is a technical argument. The lack of stable file handles would be one, and I think we came to the conclusion yesterday that this is the case.