From: Sasha Levin <sashal@kernel.org> To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Trond Myklebust <trond.myklebust@hammerspace.com>, John Hubbard <jhubbard@nvidia.com>, Sasha Levin <sashal@kernel.org>, linux-nfs@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 26/44] NFSv4: Fix a potential sleep while atomic in nfs4_do_reclaim() Date: Tue, 13 Aug 2019 22:18:15 -0400 Message-ID: <20190814021834.16662-26-sashal@kernel.org> (raw) In-Reply-To: <20190814021834.16662-1-sashal@kernel.org> From: Trond Myklebust <trond.myklebust@hammerspace.com> [ Upstream commit c77e22834ae9a11891cb613bd9a551be1b94f2bc ] John Hubbard reports seeing the following stack trace: nfs4_do_reclaim rcu_read_lock /* we are now in_atomic() and must not sleep */ nfs4_purge_state_owners nfs4_free_state_owner nfs4_destroy_seqid_counter rpc_destroy_wait_queue cancel_delayed_work_sync __cancel_work_timer __flush_work start_flush_work might_sleep: (kernel/workqueue.c:2975: BUG) The solution is to separate out the freeing of the state owners from nfs4_purge_state_owners(), and perform that outside the atomic context. Reported-by: John Hubbard <jhubbard@nvidia.com> Fixes: 0aaaf5c424c7f ("NFS: Cache state owners after files are closed") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org> --- fs/nfs/nfs4_fs.h | 3 ++- fs/nfs/nfs4client.c | 5 ++++- fs/nfs/nfs4state.c | 27 ++++++++++++++++++++++----- 3 files changed, 28 insertions(+), 7 deletions(-) diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h index a73144b3cb8c8..22cff39cca29a 100644 --- a/fs/nfs/nfs4_fs.h +++ b/fs/nfs/nfs4_fs.h @@ -433,7 +433,8 @@ static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t); extern void nfs4_put_state_owner(struct nfs4_state_owner *); -extern void nfs4_purge_state_owners(struct nfs_server *); +extern void nfs4_purge_state_owners(struct nfs_server *, struct list_head *); +extern void nfs4_free_state_owners(struct list_head *head); extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *); extern void nfs4_put_open_state(struct nfs4_state *); extern void nfs4_close_state(struct nfs4_state *, fmode_t); diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c index 8f96f6548dc82..0924b68b56574 100644 --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -739,9 +739,12 @@ int nfs41_walk_client_list(struct nfs_client *new, static void nfs4_destroy_server(struct nfs_server *server) { + LIST_HEAD(freeme); + nfs_server_return_all_delegations(server); unset_pnfs_layoutdriver(server); - nfs4_purge_state_owners(server); + nfs4_purge_state_owners(server, &freeme); + nfs4_free_state_owners(&freeme); } /* diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 85ec07e4aa91b..f92bfc787c5fe 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -614,24 +614,39 @@ void nfs4_put_state_owner(struct nfs4_state_owner *sp) /** * nfs4_purge_state_owners - Release all cached state owners * @server: nfs_server with cached state owners to release + * @head: resulting list of state owners * * Called at umount time. Remaining state owners will be on * the LRU with ref count of zero. + * Note that the state owners are not freed, but are added + * to the list @head, which can later be used as an argument + * to nfs4_free_state_owners. */ -void nfs4_purge_state_owners(struct nfs_server *server) +void nfs4_purge_state_owners(struct nfs_server *server, struct list_head *head) { struct nfs_client *clp = server->nfs_client; struct nfs4_state_owner *sp, *tmp; - LIST_HEAD(doomed); spin_lock(&clp->cl_lock); list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) { - list_move(&sp->so_lru, &doomed); + list_move(&sp->so_lru, head); nfs4_remove_state_owner_locked(sp); } spin_unlock(&clp->cl_lock); +} - list_for_each_entry_safe(sp, tmp, &doomed, so_lru) { +/** + * nfs4_purge_state_owners - Release all cached state owners + * @head: resulting list of state owners + * + * Frees a list of state owners that was generated by + * nfs4_purge_state_owners + */ +void nfs4_free_state_owners(struct list_head *head) +{ + struct nfs4_state_owner *sp, *tmp; + + list_for_each_entry_safe(sp, tmp, head, so_lru) { list_del(&sp->so_lru); nfs4_free_state_owner(sp); } @@ -1782,12 +1797,13 @@ static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recov struct nfs4_state_owner *sp; struct nfs_server *server; struct rb_node *pos; + LIST_HEAD(freeme); int status = 0; restart: rcu_read_lock(); list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { - nfs4_purge_state_owners(server); + nfs4_purge_state_owners(server, &freeme); spin_lock(&clp->cl_lock); for (pos = rb_first(&server->state_owners); pos != NULL; @@ -1816,6 +1832,7 @@ static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recov spin_unlock(&clp->cl_lock); } rcu_read_unlock(); + nfs4_free_state_owners(&freeme); return 0; } -- 2.20.1
next prev parent reply index Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-08-14 2:17 [PATCH AUTOSEL 4.14 01/44] iio: adc: max9611: Fix misuse of GENMASK macro Sasha Levin 2019-08-14 2:17 ` [PATCH AUTOSEL 4.14 02/44] HID: Add 044f:b320 ThrustMaster, Inc. 2 in 1 DT Sasha Levin 2019-08-14 2:17 ` [PATCH AUTOSEL 4.14 03/44] MIPS: kernel: only use i8253 clocksource with periodic clockevent Sasha Levin 2019-08-14 2:17 ` [PATCH AUTOSEL 4.14 04/44] mips: fix cacheinfo Sasha Levin 2019-08-14 2:17 ` [PATCH AUTOSEL 4.14 05/44] netfilter: ebtables: fix a memory leak bug in compat Sasha Levin 2019-08-14 2:17 ` [PATCH AUTOSEL 4.14 06/44] ASoC: dapm: Fix handling of custom_stop_condition on DAPM graph walks Sasha Levin 2019-08-14 2:17 ` [PATCH AUTOSEL 4.14 07/44] bonding: Force slave speed check after link state recovery for 802.3ad Sasha Levin 2019-08-14 2:17 ` [PATCH AUTOSEL 4.14 08/44] can: dev: call netif_carrier_off() in register_candev() Sasha Levin 2019-08-14 2:17 ` [PATCH AUTOSEL 4.14 09/44] ASoC: Fail card instantiation if DAI format setup fails Sasha Levin 2019-08-14 2:17 ` [PATCH AUTOSEL 4.14 10/44] st21nfca_connectivity_event_received: null check the allocation Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 11/44] st_nci_hci_connectivity_event_received: " Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 12/44] ASoC: ti: davinci-mcasp: Correct slot_width posed constraint Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 13/44] net: usb: qmi_wwan: Add the BroadMobi BM818 card Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 14/44] qed: RDMA - Fix the hw_ver returned in device attributes Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 15/44] isdn: mISDN: hfcsusb: Fix possible null-pointer dereferences in start_isoc_chain() Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 16/44] netfilter: ipset: Fix rename concurrency with listing Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 17/44] netfilter: ebtables: also count base chain policies Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 18/44] driver core: Fix use-after-free and double free on glue directory Sasha Levin 2019-08-14 7:37 ` Greg Kroah-Hartman 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 19/44] isdn: hfcsusb: Fix mISDN driver crash caused by transfer buffer on the stack Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 20/44] perf bench numa: Fix cpu0 binding Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 21/44] Input: kbtab - sanity check for endpoint type Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 22/44] net: usb: pegasus: fix improper read if get_registers() fail Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 23/44] can: sja1000: force the string buffer NULL-terminated Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 24/44] can: peak_usb: " Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 25/44] net/ethernet/qlogic/qed: " Sasha Levin 2019-08-14 2:18 ` Sasha Levin [this message] 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 27/44] HID: holtek: test for sanity of intfdata Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 28/44] HID: input: fix a4tech horizontal wheel custom usage Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 29/44] SMB3: Kernel oops mounting a encryptData share with CONFIG_DEBUG_VIRTUAL Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 30/44] HID: hiddev: avoid opening a disconnected device Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 31/44] HID: hiddev: do cleanup in failure of opening a device Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 32/44] Input: iforce - add sanity checks Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 33/44] net: cxgb3_main: Fix a resource leak in a error path in 'init_one()' Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 34/44] net: hisilicon: make hip04_tx_reclaim non-reentrant Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 35/44] net: hisilicon: fix hip04-xmit never return TX_BUSY Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 36/44] net: hisilicon: Fix dma_map_single failed on arm64 Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 37/44] libata: have ata_scsi_rw_xlat() fail invalid passthrough requests Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 38/44] libata: add SG safety checks in SFF pio transfers Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 39/44] x86/lib/cpu: Address missing prototypes warning Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 40/44] drm/vmwgfx: fix memory leak when too many retries have occurred Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 41/44] perf ftrace: Fix failure to set cpumask when only one cpu is present Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 42/44] perf cpumap: Fix writing to illegal memory in handling cpumap mask Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 43/44] perf pmu-events: Fix missing "cpu_clk_unhalted.core" event Sasha Levin 2019-08-14 2:18 ` [PATCH AUTOSEL 4.14 44/44] selftests: kvm: Adding config fragments Sasha Levin
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