On Tue, 2023-10-31 at 08:33 +1100, NeilBrown wrote:
> On Tue, 31 Oct 2023, Jeff Layton wrote:
> > Once we've set the nfsd_serv pointer in nfsd_svc, we still need to call
> > nfsd_last_thread if the server fails to be started. Remove the special
> > casing for nfsd_up_before case since shutting down the per-net stuff is
> > also handled by nfsd_last_thread.
> >
> > Finally, add a new special case at the start and skip doing anything if
> > the service already exists, 0 threads were requested and
> > serv->sv_nrthreads is 0.
>
> This is very similar to my
> Commit bf32075256e9 ("NFSD: simplify error paths in nfsd_svc()")
>
> The main difference being that special case you mention. I don't like
> that bit.
> If I run "rpc.nfsd 0" then I want the nfsd_svc to be destroyed, whether
> there were threads running or not.
>
> Is there a reason my patch isn't sufficient?
>
Ok, I wasn't sure whether that was the desired behavior or not. Your
patch should be fine actually, and it has already had some testing, so
let's just mark that for stable?
> Thanks,
> NeilBrown
>
>
> >
> > Fixes: 9f28a971ee9f ("nfsd: separate nfsd_last_thread() from nfsd_put()")
> > Reported-by: Zhi Li <yieli@xxxxxxxxxx>
> > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> > ---
> > Here's what I was thinking for a targeted patch for stable. Testing it
> > now, but I won't have results until tomorrow.
> > ---
> > fs/nfsd/nfssvc.c | 15 +++++----------
> > 1 file changed, 5 insertions(+), 10 deletions(-)
> >
> > diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
> > index 3deef000afa9..187b68769815 100644
> > --- a/fs/nfsd/nfssvc.c
> > +++ b/fs/nfsd/nfssvc.c
> > @@ -787,7 +787,6 @@ int
> > nfsd_svc(int nrservs, struct net *net, const struct cred *cred)
> > {
> > int error;
> > - bool nfsd_up_before;
> > struct nfsd_net *nn = net_generic(net, nfsd_net_id);
> > struct svc_serv *serv;
> >
> > @@ -797,8 +796,9 @@ nfsd_svc(int nrservs, struct net *net, const struct cred *cred)
> > nrservs = max(nrservs, 0);
> > nrservs = min(nrservs, NFSD_MAXSERVS);
> > error = 0;
> > + serv = nn->nfsd_serv;
> >
> > - if (nrservs == 0 && nn->nfsd_serv == NULL)
> > + if (nrservs == 0 && (serv == NULL || serv->sv_nrthreads == 0))
> > goto out;
> >
> > strscpy(nn->nfsd_name, utsname()->nodename,
> > @@ -808,22 +808,17 @@ nfsd_svc(int nrservs, struct net *net, const struct cred *cred)
> > if (error)
> > goto out;
> >
> > - nfsd_up_before = nn->nfsd_net_up;
> > serv = nn->nfsd_serv;
> >
> > error = nfsd_startup_net(net, cred);
> > if (error)
> > goto out_put;
> > error = svc_set_num_threads(serv, NULL, nrservs);
> > - if (error)
> > - goto out_shutdown;
> > - error = serv->sv_nrthreads;
> > if (error == 0)
> > - nfsd_last_thread(net);
> > -out_shutdown:
> > - if (error < 0 && !nfsd_up_before)
> > - nfsd_shutdown_net(net);
> > + error = serv->sv_nrthreads;
> > out_put:
> > + if (serv->sv_nrthreads == 0)
> > + nfsd_last_thread(net);
> > /* Threads now hold service active */
> > if (xchg(&nn->keep_active, 0))
> > svc_put(serv);
> >
> > ---
> > base-commit: 31b5a36c4b88b44c91cdd523997b1e86fb47339d
> > change-id: 20231030-kdevops-5f7366897ef4
> >
> > Best regards,
> > --
> > Jeff Layton <jlayton@xxxxxxxxxx>
> >
> >
>
--
Jeff Layton <jlayton@xxxxxxxxxx>
