Re: [PATCH v2] nfs: add dummy definition for nfsd_file

[Mike Snitzer <snitzer@kernel.org>]

On Wed, Apr 16, 2025 at 09:31:55AM -0400, Chuck Lever wrote:
> On 4/15/25 10:41 PM, Vincent Mailhol wrote:
> > +CC: Neil Brown
> > +CC: Olga Kornievskaia
> > +CC: Dai Ngo
> > +CC: Tom Talpey
> > +CC: Trond Myklebust
> > +CC: Anna Schumaker
> > 
> > (just to make sure that anyone listed in
> > 
> >   ./scripts/get_maintainer.pl fs/nfs_common/nfslocalio.c
> > 
> > get copied).
> > 
> > Here is the link to the full thread:
> > 
> >   https://lore.kernel.org/all/Z_coQbSdvMWD92IA@kernel.org/
> > 
> > 
> > On 10/04/2025 at 11:09, Mike Snitzer:
> >> Add dummy definition for nfsd_file in both nfslocalio.c and localio.c
> >> so various compilers (e.g. gcc 8.5.0 and 9.5.0) can be used. Otherwise
> >> RCU code (rcu_dereference and rcu_access_pointer) will dereference
> >> what should just be an opaque pointer (by using typeof(*ptr)).
> >>
> >> Fixes: 86e00412254a ("nfs: cache all open LOCALIO nfsd_file(s) in client")
> >> Cc: stable@vger.kernel.org
> >> Tested-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
> >> Tested-by: Pali Rohár <pali@kernel.org>
> >> Tested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
> >> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
> > 
> > Hi everyone,
> > 
> > The build has been broken for several weeks already. Does anyone have
> > intention to pick-up this patch?
> > 
> > (please ignore if someone already picked it up and if it is already on
> > its way to Linus's tree).
> 
> I assumed that, like all LOCALIO-related changes, this fix would go
> in through the NFS client tree. Let me know if it needs to go via NFSD.

Since we haven't heard from Trond or Anna about it, I think you'd be
perfectly fine to pick it up.  It is a compiler fixup associated with
nfd_file being kept opaque to the client -- but given it is "struct
nfsd_file" that gives you full license to grab it (IMO).

I'm also unaware of any conflicting changes in the NFS client tree.