[Dovecot] dovecot servers hanging with fuse/glusterfs errors

[Jordi Moles]

hi.

i've got a clustered mail system with glusterfs and some postfix, 
squirrelmail and dovecot machines sharing the same storage system 
through glusterfs.
each server has only postfix or squirrel or dovecot installed on it.
The thing is... dovecot servers hang very often and the last thing they 
always log is this:

*************

login: Unable to handle kernel paging request at 0000000000100108 RIP:
[<ffffffff88020838>] :fuse:request_end+0x45/0x109
PGD 1f729067 PUD 1faae067 PMD 0
Oops: 0002 [1] SMP
CPU 0
Modules linked in: ipv6 fuse dm_snapshot dm_mirror dm_mod
Pid: 678, comm: glusterfs Not tainted 2.6.18-xen #1
RIP: e030:[<ffffffff88020838>]  [<ffffffff88020838>] 
:fuse:request_end+0x45/0x109
RSP: e02b:ffff88001f04dd68  EFLAGS: 00010246
RAX: 0000000000200200 RBX: ffff88001db9fa58 RCX: ffff88001db9fa68
RDX: 0000000000100100 RSI: ffff88001db9fa58 RDI: ffff88001f676400
RBP: ffff88001f676400 R08: 00000000204abb00 R09: ffff88001db9fb58
R10: 0000000000000008 R11: ffff88001f04dcf0 R12: 0000000000000000
R13: ffff88001db9fa90 R14: ffff88001f04ddf8 R15: 0000000000000001
FS:  00002b29187c53b0(0000) GS:ffffffff804cd000(0000) 
knlGS:0000000000000000
CS:  e033 DS: 0000 ES: 0000
Process glusterfs (pid: 678, threadinfo ffff88001f04c000, task 
ffff88001fc5a860)
Stack:  ffff88001db9fa58 ffff88001f676400 00000000fffffffe ffffffff88021056
ffff88001f04def8 000000301f04de88 ffffffff8020dd40 ffff88001f04ddb8
ffffffff80225ca3 ffff88001de23500 ffffffff803ef023 ffff88001f04de98
Call Trace:
[<ffffffff88021056>] :fuse:fuse_dev_readv+0x385/0x435
[<ffffffff8020dd40>] monotonic_clock+0x35/0x7d
[<ffffffff80225ca3>] deactivate_task+0x1d/0x28
[<ffffffff803ef023>] thread_return+0x0/0x120
[<ffffffff802801d3>] do_readv_writev+0x271/0x294
[<ffffffff802274c7>] default_wake_function+0x0/0xe
[<ffffffff803f0976>] __down_read+0x12/0xec
[<ffffffff88021120>] :fuse:fuse_dev_read+0x1a/0x1f
[<ffffffff802804bc>] vfs_read+0xcb/0x171
[<ffffffff802274c7>] default_wake_function+0x0/0xe
[<ffffffff8028089b>] sys_read+0x45/0x6e
[<ffffffff8020a436>] system_call+0x86/0x8b
[<ffffffff8020a3b0>] system_call+0x0/0x8b


Code: 48 89 42 08 48 89 10 48 c7 41 08 00 02 20 00 f6 46 30 08 48
RIP  [<ffffffff88020838>] :fuse:request_end+0x45/0x109
RSP <ffff88001f04dd68>
CR2: 0000000000100108
 dovecot01gluster01 kernel: Oops: 0002 [1] SMP
                                                dovecot01gluster01 
kernel: CR2: 0000000000100108
                                                                                                
<3>BUG: soft lockup detected on CPU#0!

Call Trace:
<IRQ> [<ffffffff80257f78>] softlockup_tick+0xd8/0xea
[<ffffffff8020f110>] timer_interrupt+0x3a9/0x405
[<ffffffff80258264>] handle_IRQ_event+0x4e/0x96
[<ffffffff80258350>] __do_IRQ+0xa4/0x105
[<ffffffff8020b0e8>] call_softirq+0x1c/0x28
[<ffffffff8020cecb>] do_IRQ+0x65/0x73
[<ffffffff8034a8c1>] evtchn_do_upcall+0xac/0x12d
[<ffffffff8020ac1e>] do_hypervisor_callback+0x1e/0x2c
<EOI> [<ffffffff802d6f56>] dummy_inode_permission+0x0/0x3
[<ffffffff8028c9b8>] do_lookup+0x63/0x173
[<ffffffff803f1232>] .text.lock.spinlock+0x0/0x8a
[<ffffffff8802144c>] :fuse:request_send+0x1b/0x2a8
[<ffffffff8028f0d6>] __link_path_walk+0xdf2/0xf3c
[<ffffffff80261275>] __do_page_cache_readahead+0x8a/0x28f
[<ffffffff8802249f>] :fuse:fuse_dentry_revalidate+0x94/0x120
[<ffffffff80299838>] mntput_no_expire+0x19/0x8b
[<ffffffff8028f2f3>] link_path_walk+0xd3/0xe5
[<ffffffff8029571e>] __d_lookup+0xb0/0xff
[<ffffffff8028ca92>] do_lookup+0x13d/0x173
[<ffffffff8028e687>] __link_path_walk+0x3a3/0xf3c
[<ffffffff8028f27c>] link_path_walk+0x5c/0xe5
[<ffffffff80219b90>] do_page_fault+0xee9/0x1215
[<ffffffff8027e38d>] fd_install+0x25/0x5f
[<ffffffff8025daac>] filemap_nopage+0x188/0x324
[<ffffffff8028f6df>] do_path_lookup+0x270/0x2ec
[<ffffffff8028e0c6>] getname+0x15b/0x1c1
[<ffffffff8028ff52>] __user_walk_fd+0x37/0x4c
[<ffffffff80288883>] vfs_stat_fd+0x1b/0x4a
[<ffffffff80219b90>] do_page_fault+0xee9/0x1215
[<ffffffff8027e38d>] fd_install+0x25/0x5f
[<ffffffff80239287>] do_sigaction+0x7a/0x1f3
[<ffffffff80288a4e>] sys_newstat+0x19/0x31
[<ffffffff80239495>] sys_rt_sigaction+0x59/0x98
[<ffffffff8020ab73>] error_exit+0x0/0x71
[<ffffffff8020a436>] system_call+0x86/0x8b
[<ffffffff8020a3b0>] system_call+0x0/0x8b



*************

these are basic debian etch brand new set ups, they have nothing else 
than dovecot and glusterfs-client installed on them. The thing is all 
machines i've got have the very same version of glusterfs-client, but 
only the dovecot ones hang.

Do you have any idea?

Thank you.