I have a machine running 4.1.13 where this warning triggered. Before
you ask, I have a few machines running that kernel with the same nfs
mounts and roughly the same workload and it happened only this one time.
So I am guessing it will be hard to reproduce
[949229.574284] ------------[ cut here ]------------
[949229.574306] WARNING: CPU: 11 PID: 100 at fs/nfs/inode.c:121 nfs_clear_inode+0x6a/0xa0 [nfs]()
[949229.574319] Modules linked in: tcp_diag inet_diag nfnetlink_queue nfnetlink_log nfnetlink nfsd nfsv3 nfs_acl rpcsec_gss_krb5 auth_rpcgss oid_registry nfsv4 nfs lockd grace sunrpc fscache rdma_ucm rdma_cm iw_cm ib_uverbs ib_cm ib_sa ib_mad ib_core ib_addr hhostname(O) ipmi_watchdog binfmt_misc gpio_ich serio_raw pcspkr coretemp i2c_i801 lpc_ich ioatdma mfd_core dca i5500_temp ipmi_si ipmi_poweroff ipmi_devintf ipv6 autofs4 sr_mod cdrom sg usbhid crc32c_intel uhci_hcd ehci_pci ehci_hcd ahci libahci usbcore usb_common
[949229.574356] CPU: 11 PID: 100 Comm: kswapd0 Tainted: G O 4.1.13 #1
[949229.574357] Hardware name: Supermicro X8DTU/X8DTU, BIOS 2.1a 09/21/11
[949229.574358] ffffffffa0e92623 ffff880630093af8 ffffffff81591e69 0000000000000007
[949229.574361] 0000000000000000 ffff880630093b38 ffffffff8105925a 000000214190340a
[949229.574363] ffff88012aef4ac8 ffff88012aef4bc8 ffffffffa0e90b80 ffff880630093cf8
[949229.574365] Call Trace:
[949229.574371] [<ffffffff81591e69>] dump_stack+0x45/0x57
[949229.574375] [<ffffffff8105925a>] warn_slowpath_common+0x8a/0xc0
[949229.574377] [<ffffffff8105934a>] warn_slowpath_null+0x1a/0x20
[949229.574384] [<ffffffffa0e7a4ea>] nfs_clear_inode+0x6a/0xa0 [nfs]
[949229.574392] [<ffffffffa0e7c8ad>] nfs_evict_inode+0x2d/0x40 [nfs]
[949229.574395] [<ffffffff8119b2e3>] evict+0xb3/0x1a0
[949229.574397] [<ffffffff8119b411>] dispose_list+0x41/0x50
[949229.574399] [<ffffffff8119c3eb>] prune_icache_sb+0x4b/0x60
[949229.574402] [<ffffffff811833af>] super_cache_scan+0x15f/0x1b0
[949229.574406] [<ffffffff8113ac59>] shrink_slab.part.56.constprop.68+0x1b9/0x340
[949229.574409] [<ffffffff8113e0e5>] shrink_zone+0x155/0x190
[949229.574410] [<ffffffff8113ecd0>] kswapd+0x510/0x980
[949229.574413] [<ffffffff8113e7c0>] ? zone_reclaim+0x220/0x220
[949229.574417] [<ffffffff81075f0b>] kthread+0xdb/0x100
[949229.574419] [<ffffffff81075e30>] ? kthread_create_on_node+0x180/0x180
[949229.574422] [<ffffffff81598412>] ret_from_fork+0x42/0x70
[949229.574424] [<ffffffff81075e30>] ? kthread_create_on_node+0x180/0x180
[949229.574426] ---[ end trace 119ebcc8a1a978af ]---
--
Guillaume Morin <[email protected]>