Comment 5 for bug 769927

[ 661.863116] BUG: Dentry f6bcb000{i=145066,n=} still in use (1) [unmount of nfs4 0:1c]
[ 661.863138] ------------[ cut here ]------------
[ 661.863173] kernel BUG at /build/buildd/linux-2.6.38/fs/dcache.c:947!
[ 661.863209] invalid opcode: 0000 [#1] SMP
[ 661.863238] last sysfs file: /sys/devices/pci0000:00/0000:00:19.0/net/eth0/statistics/collisions
[ 661.863289] Modules linked in: nls_utf8 udf snd_hrtimer binfmt_misc microcode parport_pc ppdev autofs4 nfsd exportfs nfs lockd fscache nfs_acl auth_rpcgss sunrpc snd_hda_codec_hdmi snd_hda_codec_idt snd_hda_intel snd_hda_codec snd_usb_audio snd_hwdep snd_usbmidi_lib snd_pcm coretemp snd_seq_midi snd_seq_midi_event snd_rawmidi lm85 hwmon_vid i915 uvcvideo drm_kms_helper snd_seq i2c_i801 videodev drm snd_timer lp snd_seq_device psmouse joydev snd i2c_algo_bit parport soundcore snd_page_alloc serio_raw video usbhid hid raid10 raid456 async_raid6_recov async_pq firewire_ohci usb_storage firewire_core uas e1000e crc_itu_t raid6_pq async_xor async_memcpy async_tx raid1 raid0 multipath linear dm_raid45 xor
[ 661.863787]
[ 661.863799] Pid: 3434, comm: umount.nfs Tainted: G W 2.6.38-8-generic #42-Ubuntu /DG45ID
[ 661.863868] EIP: 0060:[<c1139629>] EFLAGS: 00010282 CPU: 0
[ 661.863904] EIP is at shrink_dcache_for_umount_subtree+0x1c9/0x1d0
[ 661.863938] EAX: 0000005f EBX: f8e66a09 ECX: c1739ba8 EDX: 00000000
[ 661.863973] ESI: f6bcb000 EDI: f6c5375c EBP: e5a75eb0 ESP: e5a75e7c
[ 661.864007] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[ 661.864037] Process umount.nfs (pid: 3434, ti=e5a74000 task=e5a68ca0 task.ti=e5a74000)
[ 661.864080] Stack:
[ 661.864094] c16918d0 f6bcb000 00145066 f6bcb024 00000001 f8e66a09 f6c5375c f6d3e500
[ 661.864155] f6bcb4cc f6bcb024 f6c53600 f6bcb800 f6bcb84c e5a75ec4 c113b690 f6c53600
[ 661.864214] e6e11800 f8e64ae0 e5a75ee0 c1128be7 e5a75eec f8e60206 0000001c e6e11800
[ 661.864272] Call Trace:
[ 661.864290] [<c113b690>] shrink_dcache_for_umount+0x50/0x60
[ 661.864325] [<c1128be7>] generic_shutdown_super+0x27/0xe0
[ 661.864369] [<f8e60206>] ? nfs_super_return_all_delegations+0x66/0x80 [nfs]
[ 661.864409] [<c1128d31>] kill_anon_super+0x11/0x50
[ 661.864444] [<f8e41390>] nfs4_kill_super+0x30/0x80 [nfs]
[ 661.864476] [<c11290cd>] deactivate_locked_super+0x3d/0x60
[ 661.864508] [<c1129b98>] deactivate_super+0x48/0x70
[ 661.864537] [<c1141400>] mntput_no_expire+0x90/0xd0
[ 661.865815] [<c1141458>] mntput+0x18/0x30
[ 661.865815] [<c1141b9e>] release_mounts+0x5e/0x80
[ 661.865815] [<c1142053>] do_umount+0xb3/0x1b0
[ 661.865815] [<c121b398>] ? security_capable+0x28/0x30
[ 661.865815] [<c11421fe>] sys_umount+0xae/0xc0
[ 661.865815] [<c114222e>] sys_oldumount+0x1e/0x20
[ 661.865815] [<c1509bf4>] syscall_call+0x7/0xb
[ 661.865815] Code: 03 8b 51 60 89 44 24 10 8b 45 f0 89 7c 24 18 89 5c 24 14 89 54 24 08 89 74 24 04 89 44 24 0c c7 04 24 d0 18 69 c1 e8 26 db 3c 00 <0f> 0b 0f 0b 8d 76 00 55 89 e5 83 ec 08 89 1c 24 89 74 24 04 3e
[ 661.865815] EIP: [<c1139629>] shrink_dcache_for_umount_subtree+0x1c9/0x1d0 SS:ESP 0068:e5a75e7c
[ 661.902862] ---[ end trace 174f5c548ffb60b5 ]---