This is a note to let you know that I've just added the patch titled nfsd: register pernet ops last, unregister first to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nfsd-register-pernet-ops-last-unregister-first.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit da3b7c33130db145816d6404c837aaeafca3baab Author: J. Bruce Fields <bfields@xxxxxxxxxx> Date: Wed Feb 3 11:42:13 2021 -0500 nfsd: register pernet ops last, unregister first [ Upstream commit bd5ae9288d6451bd346a1b4a59d4fe7e62ba29b7 ] These pernet operations may depend on stuff set up or torn down in the module init/exit functions. And they may be called at any time in between. So it makes more sense for them to be the last to be registered in the init function, and the first to be unregistered in the exit function. In particular, without this, the drc slab is being destroyed before all the per-net drcs are shut down, resulting in an "Objects remaining in nfsd_drc on __kmem_cache_shutdown()" warning in exit_nfsd. Reported-by: Zhi Li <yieli@xxxxxxxxxx> Fixes: 3ba75830ce17 "nfsd4: drc containerization" Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index be418fccc9d86..7f39d6091dfa0 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -1523,12 +1523,9 @@ static int __init init_nfsd(void) int retval; printk(KERN_INFO "Installing knfsd (copyright (C) 1996 okir@xxxxxxxxxxxx).\n"); - retval = register_pernet_subsys(&nfsd_net_ops); - if (retval < 0) - return retval; retval = register_cld_notifier(); if (retval) - goto out_unregister_pernet; + return retval; retval = nfsd4_init_slabs(); if (retval) goto out_unregister_notifier; @@ -1546,9 +1543,14 @@ static int __init init_nfsd(void) goto out_free_lockd; retval = register_filesystem(&nfsd_fs_type); if (retval) + goto out_free_exports; + retval = register_pernet_subsys(&nfsd_net_ops); + if (retval < 0) goto out_free_all; return 0; out_free_all: + unregister_pernet_subsys(&nfsd_net_ops); +out_free_exports: remove_proc_entry("fs/nfs/exports", NULL); remove_proc_entry("fs/nfs", NULL); out_free_lockd: @@ -1562,13 +1564,12 @@ static int __init init_nfsd(void) nfsd4_free_slabs(); out_unregister_notifier: unregister_cld_notifier(); -out_unregister_pernet: - unregister_pernet_subsys(&nfsd_net_ops); return retval; } static void __exit exit_nfsd(void) { + unregister_pernet_subsys(&nfsd_net_ops); nfsd_drc_slab_free(); remove_proc_entry("fs/nfs/exports", NULL); remove_proc_entry("fs/nfs", NULL); @@ -1579,7 +1580,6 @@ static void __exit exit_nfsd(void) nfsd_fault_inject_cleanup(); unregister_filesystem(&nfsd_fs_type); unregister_cld_notifier(); - unregister_pernet_subsys(&nfsd_net_ops); } MODULE_AUTHOR("Olaf Kirch <okir@xxxxxxxxxxxx>");