linux-kernel - Re: [PATCH 00/29] fs: require filesystems to explicitly opt-in to nfsd export support

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Message-ID: <aXCj9ooYaqsL9oyP@infradead.org>
Date: Wed, 21 Jan 2026 02:01:26 -0800
From: Christoph Hellwig <hch@...radead.org>
To: Jeff Layton <jlayton@...nel.org>
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Subject: Re: [PATCH 00/29] fs: require filesystems to explicitly opt-in to
 nfsd export support

On Tue, Jan 20, 2026 at 07:50:32AM -0500, Jeff Layton wrote:
> At this point, maybe we should just go with Neil's 
> EXPORT_OP_SUPPORTS_NFS_EXPORT or something. It's much more arbitrary,
> than trying to base this on criteria about filehandle stability, but it
> would give us the effect we want.

We'll still need a stable handles flag, and expose it to userspace
to avoid applications being tricked into using broken non-stable
file handles.  We should have caught that when they were added, but
didn't unfortunately.