On Fri, Aug 23, 2024 at 11:35:28AM +0800, Li Lingfeng wrote:
[ snipped ]
> [ 91.319328] Kernel panic - not syncing: Fatal exception
> [ 91.320712] Kernel Offset: disabled
> [ 91.321189] ---[ end Kernel panic - not syncing: Fatal exception ]---
>
> Both of them were introduced by commit 9f28a971ee9f ("nfsd: separate
> nfsd_last_thread() from nfsd_put()") since this patch changes the behavior
> of the error path.
>
> I confirmed this by fixing both issues with the following changes:
> diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
> index ee5713fca187..05d4b463c16b 100644
> --- a/fs/nfsd/nfssvc.c
> +++ b/fs/nfsd/nfssvc.c
> @@ -811,6 +811,8 @@ nfsd_svc(int nrservs, struct net *net, const struct cred
> *cred)
> if (error < 0 && !nfsd_up_before)
> nfsd_shutdown_net(net);
> out_put:
> + if (error < 0)
> + nfsd_last_thread(net);
> /* Threads now hold service active */
> if (xchg(&nn->keep_active, 0))
> svc_put(serv);
>
> They have been fixed by commit bf32075256e9 ("NFSD: simplify error paths in
> nfsd_svc()") in mainline.
>
> Maybe it would be a good idea to push it to the LTS branches.
To be clear, by "push it to LTS" I assume you mean apply bf32075?
I have now applied commit bf32075256e9 ("NFSD: simplify error paths
in nfsd_svc()") to nfsd-6.6.y, nfsd-5.15.y, and nfsd-5.10.y in my
kernel.org git repo, for testing.
https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git
I will run these three against the usual NFSD CI today, but feel
free to try them out yourself and report your results.
Now unfortunately 6.1.y is still "special." It appears that commit
9f28a971ee9f ("nfsd: separate nfsd_last_thread() from nfsd_put()")
was reverted in that kernel, and the fix you mention here does not
cleanly apply to v6.1.106. Based on some previous comments on this
list, I think I need to fix up v6.1 LTS to be like the other three
kernels, and then apply bf32075.
--
Chuck Lever
