Re: 2.6.19-rc1-mm1

["Michal Piotrowski" <michal.k.k.piotrowski@gmail.com>]

Hi,

On 10/10/06, Andrew Morton <akpm@osdl.org> wrote:
>
> ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.19-rc1/2.6.19-rc1-mm1/
>

Kernel 2.6.19-rc1-mm1 + Neil's avoid_lockdep_warning_in_md.patch
(http://www.ussg.iu.edu/hypermail/linux/kernel/0610.1/0642.html)

(I'll try to reproduce this without Neil's patch).

echo shutdown > /sys/power/disk; echo disk > /sys/power/state

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.19-rc1-mm1 #4
-------------------------------------------------------
bash/2404 is trying to acquire lock:
 ((cpu_chain).rwsem){..--}, at: [<c012e6a0>]
blocking_notifier_call_chain+0x11/0x2d

but task is already holding lock:
 (workqueue_mutex){--..}, at: [<c0313dea>] mutex_lock+0x1c/0x1f

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (workqueue_mutex){--..}:
       [<c013a4d0>] add_lock_to_list+0x5c/0x7a
       [<c013c5f5>] __lock_acquire+0x9f3/0xaef
       [<c013ca5b>] lock_acquire+0x71/0x91
       [<c0313baf>] __mutex_lock_slowpath+0xd2/0x2f1
       [<c0313dea>] mutex_lock+0x1c/0x1f
       [<c0131767>] workqueue_cpu_callback+0x109/0x1ff
       [<c012e30f>] notifier_call_chain+0x20/0x31
       [<c012e6ac>] blocking_notifier_call_chain+0x1d/0x2d
       [<c014126b>] _cpu_down+0x48/0x1ff
       [<c01415fc>] disable_nonboot_cpus+0x9b/0x12f
       [<c0146bd3>] prepare_processes+0xf/0x73
       [<c0146e78>] pm_suspend_disk+0xa/0x11c
       [<c01460d4>] enter_state+0x5a/0x185
       [<c0146285>] state_store+0x86/0x9c
       [<c01ad6dc>] subsys_attr_store+0x20/0x25
       [<c01ad7df>] sysfs_write_file+0xaa/0xd3
       [<c0177189>] vfs_write+0xcd/0x179
       [<c0177834>] sys_write+0x3b/0x71
       [<c0103241>] sysenter_past_esp+0x56/0x8d
       [<ffffffff>] 0xffffffff

-> #0 ((cpu_chain).rwsem){..--}:
       [<c013bbce>] print_circular_bug_tail+0x30/0x64
       [<c013c52c>] __lock_acquire+0x92a/0xaef
       [<c013ca5b>] lock_acquire+0x71/0x91
       [<c0138202>] down_read+0x28/0x3c
       [<c012e6a0>] blocking_notifier_call_chain+0x11/0x2d
       [<c014138b>] _cpu_down+0x168/0x1ff
       [<c01415fc>] disable_nonboot_cpus+0x9b/0x12f
       [<c0146bd3>] prepare_processes+0xf/0x73
       [<c0146e78>] pm_suspend_disk+0xa/0x11c
       [<c01460d4>] enter_state+0x5a/0x185
       [<c0146285>] state_store+0x86/0x9c
       [<c01ad6dc>] subsys_attr_store+0x20/0x25
       [<c01ad7df>] sysfs_write_file+0xaa/0xd3
       [<c0177189>] vfs_write+0xcd/0x179
       [<c0177834>] sys_write+0x3b/0x71
       [<c0103241>] sysenter_past_esp+0x56/0x8d
       [<ffffffff>] 0xffffffff

other info that might help us debug this:

2 locks held by bash/2404:
 #0:  (cpu_add_remove_lock){--..}, at: [<c0313dea>] mutex_lock+0x1c/0x1f
 #1:  (workqueue_mutex){--..}, at: [<c0313dea>] mutex_lock+0x1c/0x1f

stack backtrace:
 [<c01042e6>] dump_trace+0x64/0x1cd
 [<c0104461>] show_trace_log_lvl+0x12/0x25
 [<c0104a08>] show_trace+0xd/0x10
 [<c0104a4f>] dump_stack+0x19/0x1b
 [<c013bbf7>] print_circular_bug_tail+0x59/0x64
 [<c013c52c>] __lock_acquire+0x92a/0xaef
 [<c013ca5b>] lock_acquire+0x71/0x91
 [<c0138202>] down_read+0x28/0x3c
 [<c012e6a0>] blocking_notifier_call_chain+0x11/0x2d
 [<c014138b>] _cpu_down+0x168/0x1ff
 [<c01415fc>] disable_nonboot_cpus+0x9b/0x12f
 [<c0146bd3>] prepare_processes+0xf/0x73
 [<c0146e78>] pm_suspend_disk+0xa/0x11c
 [<c01460d4>] enter_state+0x5a/0x185
 [<c0146285>] state_store+0x86/0x9c
 [<c01ad6dc>] subsys_attr_store+0x20/0x25
 [<c01ad7df>] sysfs_write_file+0xaa/0xd3
 [<c0177189>] vfs_write+0xcd/0x179
 [<c0177834>] sys_write+0x3b/0x71
 [<c0103241>] sysenter_past_esp+0x56/0x8d
DWARF2 unwinder stuck at sysenter_past_esp+0x56/0x8d
Leftover inexact backtrace:
 =======================

config & dmesg http://www.stardust.webpages.pl/files/tbf/euridica/2.6.19-rc1-mm1/

Regards,
Michal

-- 
Michal K. K. Piotrowski
LTG - Linux Testers Group
(http://www.stardust.webpages.pl/ltg/)