NFSv4 mounts hungs and kernel messages were flooded by "NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence" messages

[Xeelee]

$ lsb_release -rd
Description: Ubuntu 10.04.1 LTS
Release: 10.04

NFSv4 mount of /home with krb5 authentification hungs with massive messages flooding:
[ 9780.945132] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880017377228!
[ 9975.465061] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880016914e28!
[10176.584424] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880017377e28!
[10249.886050] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880017377c28!
[10275.752257] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff8800625d1428!
[10387.410561] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880017377c28!
[10576.261126] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880016914428!
[10750.613787] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff88000aca2028!
[10837.653221] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880016918e28!
[10876.839759] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880016919828!
[11011.844423] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880017376028!
[11091.486702] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880017376628!
[11091.488320] NFS: v4 server returned a bad sequence-id error on an unconfirmed sequence ffff880017376428!

Mount line in /etc/fstab:
filer.xxxxxxxxx:/home /home nfs4 _netdev,noauto,defaults,sec=krb5p,intr,bg 0 0

$ uname -a
Linux XXX 2.6.32-25-generic #43-Ubuntu SMP Wed Sep 1 09:46:13 UTC 2010 x86_64 GNU/Linux

Further information: With ubuntu-kernel 2.6.32-24 there is no way to use the machine in any way. The mount hungs really often and many kernel-oops occurs (old dmesg with 2.6.32-24 kernel):
Linux version 2.6.32-24-generic (buildd@crested) (gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5) ) #42-Ubuntu SMP Fri Aug 20 14:21:58 UTC 2010 (Ubuntu 2.6.32-24.42-generic 2.6.32.15+drm33.5)
(kern.log):
Sep 11 23:48:42 XXX kernel: [294841.550729] Call Trace:
Sep 11 23:48:42 XXX kernel: [294841.550741] [<ffffffff81542ea7>] __mutex_lock_slowpath+0xe7/0x170
Sep 11 23:48:42 XXX kernel: [294841.550744] [<ffffffff81542d9b>] mutex_lock+0x2b/0x50
Sep 11 23:48:42 XXX kernel: [294841.550750] [<ffffffff81152339>] do_filp_open+0x3d9/0xba0
Sep 11 23:48:42 XXX kernel: [294841.550755] [<ffffffff810f4a97>] ? unlock_page+0x27/0x30
Sep 11 23:48:42 XXX kernel: [294841.550759] [<ffffffff81112f39>] ? __do_fault+0x439/0x500
Sep 11 23:48:42 XXX kernel: [294841.550763] [<ffffffff81116098>] ? handle_mm_fault+0x1a8/0x3c0
Sep 11 23:48:42 XXX kernel: [294841.550768] [<ffffffff8115ddba>] ? alloc_fd+0x10a/0x150
Sep 11 23:48:42 XXX kernel: [294841.550772] [<ffffffff811419d9>] do_sys_open+0x69/0x170
Sep 11 23:48:42 XXX kernel: [294841.550775] [<ffffffff81141b20>] sys_open+0x20/0x30
Sep 11 23:48:42 XXX kernel: [294841.550780] [<ffffffff810131b2>] system_call_fastpath+0x16/0x1b
Sep 11 23:48:42 XXX kernel: [294841.550783] INFO: task xauth:18010 blocked for more than 120 seconds.
Sep 11 23:48:42 XXX kernel: [294841.550785] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Sep 11 23:48:42 XXX kernel: [294841.550787] xauth D 0000000000000000 0 18010 1 0x00000004
Sep 11 23:48:42 XXX kernel: [294841.550791] ffff88032f45dd38 0000000000000086 0000000000015bc0 0000000000015bc0
Sep 11 23:48:42 XXX kernel: [294841.550795] ffff8802abe9df80 ffff88032f45dfd8 0000000000015bc0 ffff8802abe9dbc0
Sep 11 23:48:42 XXX kernel: [294841.550800] 0000000000015bc0 ffff88032f45dfd8 0000000000015bc0 ffff8802abe9df80
Sep 11 23:48:42 XXX kernel: [294841.550804] Call Trace:
Sep 11 23:48:42 XXX kernel: [294841.550807] [<ffffffff81542ea7>] __mutex_lock_slowpath+0xe7/0x170
Sep 11 23:48:42 XXX kernel: [294841.550811] [<ffffffff81542d9b>] mutex_lock+0x2b/0x50
Sep 11 23:48:42 XXX kernel: [294841.550814] [<ffffffff81152339>] do_filp_open+0x3d9/0xba0
Sep 11 23:48:42 XXX kernel: [294841.550817] [<ffffffff810f4a97>] ? unlock_page+0x27/0x30
Sep 11 23:48:42 XXX kernel: [294841.550820] [<ffffffff81112f39>] ? __do_fault+0x439/0x500
Sep 11 23:48:42 XXX kernel: [294841.550823] [<ffffffff81116098>] ? handle_mm_fault+0x1a8/0x3c0
Sep 11 23:48:42 XXX kernel: [294841.550826] [<ffffffff8115ddba>] ? alloc_fd+0x10a/0x150
Sep 11 23:48:42 XXX kernel: [294841.550830] [<ffffffff811419d9>] do_sys_open+0x69/0x170
Sep 11 23:48:42 XXX kernel: [294841.550833] [<ffffffff81141b20>] sys_open+0x20/0x30
Sep 11 23:48:42 XXX kernel: [294841.550836] [<ffffffff810131b2>] system_call_fastpath+0x16/0x1b

Yours, sincerly

[Victor Vargas (kamus)]

I have reassigned this issue to nfs-utils package for now