Hi,
> On Thu, 2022-12-22 at 17:38 +0800, Wang Yugui wrote:
> > Hi, Jeff Layton
> >
> > > Hi,
> > > > a nfsd_file_free panic when shudown.
> > > >
> > > > This is a kernel 6.1.1 with some nfsd 6.2 pathes.
> > > > It happened when os shutdown.
> > > >
> > > > but the reproducer is yet not clear.
> > > > we just gather the info of the attachment file.
> > >
> > > Now I can reproduce it.
> > > 1) 'tail -f xxx' to keep a file is open from nfs4 client
> > > 2) 'shutdow -r now' the nfs server.
> > >
> > > more panic info in the attachment files (panic-2.txt/panic-3.txt)
> > >
> > > >
> > > > It happened just after 'Subject: nfsd: rework refcounting in filecache'
> > > > is added, so this patch maybe related.
> >
> > It is confirmed that this panic is caused by the patch
> > 'nfsd: rework refcounting in filecache'.
> >
> > the problem is 100% reproduced when this patch is applied.
> > the problem is yet not reproduced when this patch is not applied.
> >
> > Best Regards
> > Wang Yugui (wangyugui@xxxxxxxxxxxx)
> > 2022/12/22
> >
>
> Thanks for the bug report! This patch seems to fix the problem for me.
> Can you test it and let me know whether it also fixes it for you? If so,
> I'll send this to Chuck and the list for inclusion soon.
This new patch fix the problem here too. Thanks a lot.
Best Regards
Wang Yugui (wangyugui@xxxxxxxxxxxx)
2022/12/22
>
> Thanks!
> --?
> Jeff Layton <jlayton@xxxxxxxxxx>
>
> --------------------8<--------------------------
>
> [PATCH] nfsd: shut down the NFSv4 state objects before the filecache
>
> Currently, we shut down the filecache before trying to clean up the
> stateids that depend on it, which can lead to an oops at shutdown time
> due to a refcount imbalance. Change the shutdown procedures to bring
> down the state handling infrastructure prior to shutting down the
> filecache.
>
> Reported-by: Wang Yugui <wangyugui@xxxxxxxxxxxx>
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> ---
> fs/nfsd/nfssvc.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
> index 56fba1cba3af..325d3d3f1211 100644
> --- a/fs/nfsd/nfssvc.c
> +++ b/fs/nfsd/nfssvc.c
> @@ -453,8 +453,8 @@ static void nfsd_shutdown_net(struct net *net)
> {
> struct nfsd_net *nn = net_generic(net, nfsd_net_id);
>
> - nfsd_file_cache_shutdown_net(net);
> nfs4_state_shutdown_net(net);
> + nfsd_file_cache_shutdown_net(net);
> if (nn->lockd_up) {
> lockd_down(net);
> nn->lockd_up = false;
> --
> 2.38.1
>
