[RHEL6.3] kernel BUG at fs/dcache.c:670!

Issue

crash> log

...skipping...

BUG: Dentry ffff88020484a440{i=100006,n=.vpdlock} still in use (1) [unmount of ext4 sda12]
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kernel BUG at fs/dcache.c:670!
invalid opcode: 0000 [#1] SMP 
last sysfs file: /sys/devices/virtual/block/dm-0/dev
CPU 1 
Modules linked in: softdog libcrc32c dfp_aes(P)(U) dfpmod(P)(U) dfpgplmod(U) ipv6 uinput ppdev parport_pc parport sg microcode vmware_balloon i2c_piix4 i2c_core shpchp ext4 mbcache jbd2 sd_mod crc_t10dif sr_mod cdrom vmxnet3 vmw_pvscsi pata_acpi ata_generic ata_piix dm_mirror dm_region_hash dm_log dm_mod [last unloaded: dfp_bf]

Pid: 20175, comm: umount Tainted: P           ---------------    2.6.32-279.el6.x86_64 #1 VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform
RIP: 0010:[<ffffffff811933d8>]  [<ffffffff811933d8>] shrink_dcache_for_umount_subtree+0x2a8/0x2b0
RSP: 0018:ffff88023890ddc8  EFLAGS: 00010296
RAX: 0000000000000061 RBX: ffff88020484a440 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000046 RDI: 0000000000000246
RBP: ffff88023890de08 R08: 0000000000000000 R09: ffffffff8163ab80
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000017
R13: ffffffff81a83fc0 R14: ffff88020484aed0 R15: ffff88020484a4a0
FS:  00007fbc14a1c740(0000) GS:ffff880028280000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbc14a31000 CR3: 00000002287fe000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process umount (pid: 20175, threadinfo ffff88023890c000, task ffff88022c60d500)
Stack:
 ffff880239501670 ffffffff810d327f ffff88023890dde8 ffff880239501400
<d> ffffffffa00eace0 ffffffff81c015c0 ffff880239501400 ffff880239460a80
<d> ffff88023890de28 ffffffff81193416 0000000000000286 ffff880239501400
Call Trace:
 [<ffffffff810d327f>] ? audit_putname+0x3f/0x50
 [<ffffffff81193416>] shrink_dcache_for_umount+0x36/0x60
 [<ffffffff8117d1df>] generic_shutdown_super+0x1f/0xe0
 [<ffffffff8117d2d1>] kill_block_super+0x31/0x50
 [<ffffffff8117e380>] deactivate_super+0x70/0x90
 [<ffffffff8119a3bf>] mntput_no_expire+0xbf/0x110
 [<ffffffff8119ae5b>] sys_umount+0x7b/0x3a0
 [<ffffffffa0239c74>] vpd_sys_umount+0x38/0x4e [dfpmod]
 [<ffffffff8100b0f2>] system_call_fastpath+0x16/0x1b
Code: 50 30 4c 8b 0a 31 d2 48 85 f6 74 04 48 8b 56 40 48 05 70 02 00 00 48 89 de 48 c7 c7 40 6f 7a 81 48 89 04 24 31 c0 e8 0a 9e 36 00 <0f> 0b eb fe 0f 0b eb fe 55 48 89 e5 53 48 83 ec 08 0f 1f 44 00 
RIP  [<ffffffff811933d8>] shrink_dcache_for_umount_subtree+0x2a8/0x2b0
 RSP <ffff88023890ddc8>