Kernel crashed with RIP:lockd_down() at fs/lockd/svc.c:348! in Red Hat Enterprise Linux 6

Issue

• BUG was triggered with following log.

lockd_down: no users! task=(null)
------------[ cut here ]------------
kernel BUG at fs/lockd/svc.c:348!
invalid opcode: 0000 [#1] SMP 
last sysfs file: /sys/devices/system/cpu/online
CPU 2 
Modules linked in: ext2 mptctl mptbase vxodm(P)(U) nfsd autofs4 nfs lockd fscache auth_rpcgss nfs_acl sunrpc dmpjbod(P)(U) dmpap(P)(U) dmpaa(P)(U) vxspec(P)(U) vxio(P)(U) vxdmp(P)(U) cpufreq_ondemand freq_table pcc_cpufreq ipv6 vxcafs(P)(U) vxportal(P)(U) fdd(P)(U) vxfs(P)(U) exportfs vfat fat microcode iTCO_wdt iTCO_vendor_support hpilo hpwdt serio_raw lpc_ich mfd_core tg3 ptp pps_core power_meter sg shpchp ext4 jbd2 mbcache sd_mod pata_acpi ata_generic ata_piix hpsa lpfc scsi_transport_fc scsi_tgt crc_t10dif dm_mirror dm_region_hash dm_log dm_mod [last unloaded: scsi_wait_scan]

Pid: 36083, comm: umount.nfs Tainted: P           ---------------    2.6.32-431.el6.x86_64 #1 HP ProLiant DL380p Gen8
RIP: 0010:[<ffffffffa0b72bb2>]  [<ffffffffa0b72bb2>] lockd_down+0x82/0xa0 [lockd]
RSP: 0018:ffff8802f08afe28  EFLAGS: 00010296
RAX: 0000000000000028 RBX: ffff8805e1099000 RCX: 0000000000008f9a
RDX: 0000000000000000 RSI: 0000000000000046 RDI: 0000000000000246
RBP: ffff8802f08afe28 R08: 0000000000000000 R09: ffffffff81645da0
R10: 0000000000000001 R11: 0000000000000000 R12: ffff880fdbaa9000
R13: ffffffff81c06480 R14: ffff8806e76aa800 R15: ffff880ff7b27980
FS:  00007fec8bb54700(0000) GS:ffff880061840000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00007fec8b73d930 CR3: 000000082a6a8000 CR4: 00000000001407e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process umount.nfs (pid: 36083, threadinfo ffff8802f08ae000, task ffff880a8827caa0)
Stack:
 ffff8802f08afe38 ffffffffa0b700b3 ffff8802f08afe48 ffffffffa0b8a8d4
<d> ffff8802f08afe68 ffffffffa0b8b977 ffff8806e76aa800 ffff8805e1099000
<d> ffff8802f08afe88 ffffffffa0b994a5 ffff8806e76aa800 ffffffffa0bdd580
Call Trace:
 [<ffffffffa0b700b3>] nlmclnt_done+0x13/0x20 [lockd]
 [<ffffffffa0b8a8d4>] nfs_destroy_server+0x24/0x30 [nfs]
 [<ffffffffa0b8b977>] nfs_free_server+0x97/0x130 [nfs]
 [<ffffffffa0b994a5>] nfs_kill_super+0x35/0x40 [nfs]
 [<ffffffff8118bad7>] deactivate_super+0x57/0x80
 [<ffffffff811aaaaf>] mntput_no_expire+0xbf/0x110
 [<ffffffff811ab5fb>] sys_umount+0x7b/0x3a0
 [<ffffffff8100b072>] system_call_fastpath+0x16/0x1b
Code: 71 b7 00 00 00 00 00 00 48 c7 c7 e0 c6 b7 a0 e8 95 60 9b e0 c9 c3 48 8b 35 54 b7 00 00 48 c7 c7 28 ad b7 a0 31 c0 e8 10 47 9b e0 <0f> 0b eb fe 48 c7 c7 50 ad b7 a0 31 c0 e8 fe 46 9b e0 0f 0b eb 
RIP  [<ffffffffa0b72bb2>] lockd_down+0x82/0xa0 [lockd]
 RSP <ffff8802f08afe28>