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Date:   Wed, 7 Oct 2020 16:29:20 -0400
From:   "bfields@fieldses.org" <bfields@fieldses.org>
To:     Trond Myklebust <trondmy@hammerspace.com>
Cc:     "linux-nfs@vger.kernel.org" <linux-nfs@vger.kernel.org>,
        "aglo@umich.edu" <aglo@umich.edu>,
        "bcodding@redhat.com" <bcodding@redhat.com>,
        "chuck.lever@oracle.com" <chuck.lever@oracle.com>
Subject: Re: unsharing tcp connections from different NFS mounts
Message-ID: <20201007202920.GH23452@fieldses.org>
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On Wed, Oct 07, 2020 at 07:11:49PM +0000, Trond Myklebust wrote:
> On Wed, 2020-10-07 at 14:05 -0400, bfields@fieldses.org wrote:
> > On Wed, Oct 07, 2020 at 05:29:26PM +0000, Trond Myklebust wrote:
> > > On Wed, 2020-10-07 at 13:15 -0400, Bruce Fields wrote:
> > > > Yeah, honestly I don't understand the details of that case
> > > > either.
> > > > 
> > > > (There is one related thing I'm curious about, which is how close
> > > > we
> > > > are
> > > > to keeping clients in different containers completely separate
> > > > (which
> > > > we'd need, for example, if we were to ever permit unprivileged
> > > > nfs
> > > > mounts).  It looks to me like as long as two network namespaces
> > > > use
> > > > different client identifiers, the client should keep different
> > > > state
> > > > for
> > > > them already?  Or is there more to do there?)
> > > 
> > > The containerised use case should already work. The containers have
> > > their own private uniquifiers, which can be changed
> > > via /sys/fs/nfs/net/nfs_client/identifier.
> > 
> > I was just looking at that commit (bf11fbd20b3 "NFS: Add sysfs
> > support
> > for per-container identifier"), and I'm confused by it: it adds code
> > to
> > nfs/sysfs to get and set "identifier", but nothing anywhere that
> > actually uses the value.  I can't figure out what I'm missing.
> > 
> 
> No, you're right. Something slipped under the radar there. The
> intention was that when it is set, the container-specific 'identifier'
> should replace the regular system-wide uniquifier. I thought I had
> merged patches for that, but apparently something got screwed up. Let
> me fix that up for 5.10...

Great, thanks.

--b.