Re: unable to run NFSD in container if "options sunrpc pool_mode=pernode"

[Jeff Layton <jlayton@kernel.org>]

On Fri, 2025-05-23 at 23:53 -0400, Mike Snitzer wrote:
> On Fri, May 23, 2025 at 07:09:27PM -0400, Mike Snitzer wrote:
> > On Fri, May 23, 2025 at 06:40:45PM -0400, Jeff Layton wrote:
> > > On Fri, 2025-05-23 at 18:19 -0400, Mike Snitzer wrote:
> > > > On Fri, May 23, 2025 at 02:40:17PM -0400, Jeff Layton wrote:
> > > > > On Fri, 2025-05-23 at 14:29 -0400, Mike Snitzer wrote:
> > > > > > I don't know if $SUBJECT ever worked... but with latest 6.15 or
> > > > > > nfsd-testing if I just use pool_mode=global then all is fine.
> > > > > > 
> > > > > > If pool_mode=pernode then mounting the container's NFSv3 export fails.
> > > > > > 
> > > > > > I haven't started to dig into code yet but pool_mode=pernode works
> > > > > > perfectly fine if NFSD isn't running in a container.
> > > > > > 
> > > 
> > > Oops, I went and looked and nfsd isn't running in a container on these
> > > boxes. There are some other containerized apps running on the box, but
> > > nfsd isn't running in a container.
> > 
> > OK.
> > 
> > > > I'm using nfs-utils-2.8.2.  I don't see any nfsd threads running if I
> > > > use "options sunrpc pool_mode=pernode".
> > > > 
> > > 
> > > I'll have a look soon, but if you figure it out in the meantime, let us
> > > know.
> > 
> > Will do.
> > 
> > Just the latest info I have, with sunrpc's pool_mode=pernode dd hangs
> > with this stack trace:
> 
> Turns out this pool_mode=pernode issue is a regression caused by the
> very recent nfs-utils 2.8.2 (I rebuilt EL10's nfs-utils package,
> because why not upgrade to the latest!?).
> 
> If I use EL9.5's latest nfs-utils-2.5.4-37.el8.x86_64 then sunrpc's
> pool_mode=pernode works fine.
> 
> And this issue doesn't have anything to do with running in a container
> (it seemed to be container related purely because I happened to be
> seeing the issue with an EL9.5 container that had the EL10-based
> nfs-utils 2.8.2 installed).
> 
> Steved, unfortunately I'm not sure what the problem is with the newer
> nfs-utils and setting "options sunrpc pool_mode=pernode"
> 

I tried to reproduce this using fedora-41 VMs (no f42 available for
virt-builder yet), but everything worked. I don't have any actual NUMA
hw here though, so maybe that matters?

Can you run this on the nfs server and send back the output? I'm
wondering if this setting might not track the module option properly on
that host for some reason:

    # nfsdctl pool-mode

-- 
Jeff Layton <jlayton@kernel.org>