Re: [PATCH 00/29] fs: require filesystems to explicitly opt-in to nfsd export support
Christoph Hellwig <[email protected]>
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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.