From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62F1BC46467 for ; Wed, 11 Jan 2023 20:17:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232920AbjAKURd (ORCPT ); Wed, 11 Jan 2023 15:17:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232509AbjAKURb (ORCPT ); Wed, 11 Jan 2023 15:17:31 -0500 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF6CE7654 for ; Wed, 11 Jan 2023 12:17:30 -0800 (PST) Received: from pps.filterd (m0246629.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 30BJkvfS004100; Wed, 11 Jan 2023 20:17:26 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id; s=corp-2022-7-12; bh=OZnvQg/eL4Raax7SxFR3KFVi03f5WH25eG6kvVbFnzA=; b=Tzav8kEOvMY5eTaR5CPYiEDC/AxL2ug52tWSy28A/GMCyU1RQSyCpOVo37hw8nbPj4lb BdhZj4DKc/XDk7n8tpYxkctVQh7/y0DqBlP+JfOEAcy4nG0mQeuBt5v2cOysHxdCXjOG x0Fdx3PANDh+dqm59wCuHipY5mDYWy8jDX8w3h5URqy+Glr02p5XZ61FhB9fHYO6My6y IYkEKHz86EW+lqhUkyko3faER/TLCW3g4cX5kvjtovAS0TV/ij6vA9npK78fXn5tPJ3x RA/Ypy+PwLCv+DQzG8c4FnzopID3eFVbXbJbAWI6BZwuh5ZF6gYgMdjdbHpd/CduWVmh vA== Received: from phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta03.appoci.oracle.com [138.1.37.129]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3n23jhr2ne-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 11 Jan 2023 20:17:25 +0000 Received: from pps.filterd (phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (8.17.1.5/8.17.1.5) with ESMTP id 30BJ9JJI005354; Wed, 11 Jan 2023 20:17:25 GMT Received: from pps.reinject (localhost [127.0.0.1]) by phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 3n1k4a84w0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 11 Jan 2023 20:17:25 +0000 Received: from phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 30BKHOJr030208; Wed, 11 Jan 2023 20:17:24 GMT Received: from ca-common-hq.us.oracle.com (ca-common-hq.us.oracle.com [10.211.9.209]) by phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTP id 3n1k4a84vp-1; Wed, 11 Jan 2023 20:17:24 +0000 From: Dai Ngo To: chuck.lever@oracle.com, jlayton@kernel.org Cc: efault@gmx.de, linux-nfs@vger.kernel.org Subject: [PATCH v2 1/1] NFSD: register/unregister of nfsd-client shrinker at nfsd startup/shutdown time Date: Wed, 11 Jan 2023 12:17:09 -0800 Message-Id: <1673468229-20039-1-git-send-email-dai.ngo@oracle.com> X-Mailer: git-send-email 1.8.3.1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.923,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2023-01-11_10,2023-01-11_02,2022-06-22_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 suspectscore=0 adultscore=0 spamscore=0 mlxscore=0 bulkscore=0 malwarescore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2212070000 definitions=main-2301110149 X-Proofpoint-GUID: A_t6u00n7OgPTs558U89EaZwn75SxTfC X-Proofpoint-ORIG-GUID: A_t6u00n7OgPTs558U89EaZwn75SxTfC Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Currently the nfsd-client shrinker is registered and unregistered at the time the nfsd module is loaded and unloaded. The problem with this is the shrinker is being registered before all of the relevant fields in nfsd_net are initialized when nfsd is started. This can lead to an oops when memory is low and the shrinker is called while nfsd is not running. This patch moves the register/unregister of nfsd-client shrinker from module load/unload time to nfsd startup/shutdown time. Fixes: 44df6f439a17 ("NFSD: add delegation reaper to react to low memory condition") Reported-by: Mike Galbraith Signed-off-by: Dai Ngo --- v2: reword change log for better description of the problem fs/nfsd/nfs4state.c | 22 +++++++++++----------- fs/nfsd/nfsctl.c | 7 +------ fs/nfsd/nfsd.h | 6 ++---- 3 files changed, 14 insertions(+), 21 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 7b2ee535ade8..a7cfefd7c205 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -4421,7 +4421,7 @@ nfsd4_state_shrinker_scan(struct shrinker *shrink, struct shrink_control *sc) return SHRINK_STOP; } -int +void nfsd4_init_leases_net(struct nfsd_net *nn) { struct sysinfo si; @@ -4443,16 +4443,6 @@ nfsd4_init_leases_net(struct nfsd_net *nn) nn->nfs4_max_clients = max_t(int, max_clients, NFS4_CLIENTS_PER_GB); atomic_set(&nn->nfsd_courtesy_clients, 0); - nn->nfsd_client_shrinker.scan_objects = nfsd4_state_shrinker_scan; - nn->nfsd_client_shrinker.count_objects = nfsd4_state_shrinker_count; - nn->nfsd_client_shrinker.seeks = DEFAULT_SEEKS; - return register_shrinker(&nn->nfsd_client_shrinker, "nfsd-client"); -} - -void -nfsd4_leases_net_shutdown(struct nfsd_net *nn) -{ - unregister_shrinker(&nn->nfsd_client_shrinker); } static void init_nfs4_replay(struct nfs4_replay *rp) @@ -8077,8 +8067,17 @@ static int nfs4_state_create_net(struct net *net) INIT_DELAYED_WORK(&nn->nfsd_shrinker_work, nfsd4_state_shrinker_worker); get_net(net); + nn->nfsd_client_shrinker.scan_objects = nfsd4_state_shrinker_scan; + nn->nfsd_client_shrinker.count_objects = nfsd4_state_shrinker_count; + nn->nfsd_client_shrinker.seeks = DEFAULT_SEEKS; + + if (register_shrinker(&nn->nfsd_client_shrinker, "nfsd-client")) + goto err_shrinker; return 0; +err_shrinker: + put_net(net); + kfree(nn->sessionid_hashtbl); err_sessionid: kfree(nn->unconf_id_hashtbl); err_unconf_id: @@ -8171,6 +8170,7 @@ nfs4_state_shutdown_net(struct net *net) struct list_head *pos, *next, reaplist; struct nfsd_net *nn = net_generic(net, nfsd_net_id); + unregister_shrinker(&nn->nfsd_client_shrinker); cancel_delayed_work_sync(&nn->laundromat_work); locks_end_grace(&nn->nfsd4_manager); diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index d1e581a60480..c2577ee7ffb2 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -1457,9 +1457,7 @@ static __net_init int nfsd_init_net(struct net *net) goto out_idmap_error; nn->nfsd_versions = NULL; nn->nfsd4_minorversions = NULL; - retval = nfsd4_init_leases_net(nn); - if (retval) - goto out_drc_error; + nfsd4_init_leases_net(nn); retval = nfsd_reply_cache_init(nn); if (retval) goto out_cache_error; @@ -1469,8 +1467,6 @@ static __net_init int nfsd_init_net(struct net *net) return 0; out_cache_error: - nfsd4_leases_net_shutdown(nn); -out_drc_error: nfsd_idmap_shutdown(net); out_idmap_error: nfsd_export_shutdown(net); @@ -1486,7 +1482,6 @@ static __net_exit void nfsd_exit_net(struct net *net) nfsd_idmap_shutdown(net); nfsd_export_shutdown(net); nfsd_netns_free_versions(net_generic(net, nfsd_net_id)); - nfsd4_leases_net_shutdown(nn); } static struct pernet_operations nfsd_net_ops = { diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index 93b42ef9ed91..fa0144a74267 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -504,8 +504,7 @@ extern void unregister_cld_notifier(void); extern void nfsd4_ssc_init_umount_work(struct nfsd_net *nn); #endif -extern int nfsd4_init_leases_net(struct nfsd_net *nn); -extern void nfsd4_leases_net_shutdown(struct nfsd_net *nn); +extern void nfsd4_init_leases_net(struct nfsd_net *nn); #else /* CONFIG_NFSD_V4 */ static inline int nfsd4_is_junction(struct dentry *dentry) @@ -513,8 +512,7 @@ static inline int nfsd4_is_junction(struct dentry *dentry) return 0; } -static inline int nfsd4_init_leases_net(struct nfsd_net *nn) { return 0; }; -static inline void nfsd4_leases_net_shutdown(struct nfsd_net *nn) {}; +static inline void nfsd4_init_leases_net(struct nfsd_net *nn) { }; #define register_cld_notifier() 0 #define unregister_cld_notifier() do { } while(0) -- 2.9.5