[ INFO: possible circular locking dependency detected ]
2.6.23-rc2-mm1 #7
-------------------------------------------------------
kacpid/53 is trying to acquire lock:
(&ec->lock){--..}, at: [<c03031a7>] mutex_lock+0x1c/0x1f
but task is already holding lock:
(&dpc->work){--..}, at: [<c012689d>] run_workqueue+0xa0/0x182
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&dpc->work){--..}:
[<c0133d24>] __lock_acquire+0x9a6/0xb6f
[<c0133f4e>] lock_acquire+0x61/0x7d
[<c01268b2>] run_workqueue+0xb5/0x182
[<c01271a9>] worker_thread+0xb7/0xc2
[<c01296c4>] kthread+0x39/0x61
[<c0104913>] kernel_thread_helper+0x7/0x10
[<ffffffff>] 0xffffffff
-> #1 (kacpid){--..}:
[<c0133d24>] __lock_acquire+0x9a6/0xb6f
[<c0133f4e>] lock_acquire+0x61/0x7d
[<c0126f62>] flush_workqueue+0x2d/0x4f
[<c01e85e0>] acpi_os_wait_events_complete+0xd/0xf
[<c01ef605>] acpi_remove_gpe_handler+0x7b/0xdd
[<c0205981>] ec_remove_handlers+0x26/0x29
[<c02062b4>] acpi_ec_add+0x8f/0x13e
[<c0205477>] acpi_device_probe+0x3e/0xdb
[<c023c4c8>] driver_probe_device+0xd7/0x14d
[<c023c652>] __driver_attach+0x6a/0xa1
[<c023baaa>] bus_for_each_dev+0x36/0x5b
[<c023c32e>] driver_attach+0x14/0x16
[<c023bd7e>] bus_add_driver+0x70/0x16c
[<c023c82d>] driver_register+0x60/0x65
[<c020577b>] acpi_bus_register_driver+0x3a/0x3c
[<c04292e4>] acpi_ec_init+0x36/0x55
[<c0416650>] kernel_init+0xc5/0x20f
[<c0104913>] kernel_thread_helper+0x7/0x10
[<ffffffff>] 0xffffffff
-> #0 (&ec->lock){--..}:
[<c0133c44>] __lock_acquire+0x8c6/0xb6f
[<c0133f4e>] lock_acquire+0x61/0x7d
[<c0303006>] __mutex_lock_slowpath+0xbc/0x241
[<c03031a7>] mutex_lock+0x1c/0x1f
[<c0205bbd>] acpi_ec_transaction+0x65/0x1c1
[<c0205d44>] acpi_ec_gpe_query+0x2b/0xab
[<c01e8602>] acpi_os_execute_deferred+0x20/0x31
[<c01268b7>] run_workqueue+0xba/0x182
[<c01271a9>] worker_thread+0xb7/0xc2
[<c01296c4>] kthread+0x39/0x61
[<c0104913>] kernel_thread_helper+0x7/0x10
[<ffffffff>] 0xffffffff
other info that might help us debug this:
2 locks held by kacpid/53:
#0: (kacpid){--..}, at: [<c0126882>] run_workqueue+0x85/0x182
#1: (&dpc->work){--..}, at: [<c012689d>] run_workqueue+0xa0/0x182
stack backtrace:
[<c0104c6a>] show_trace_log_lvl+0x12/0x25
[<c0105552>] show_trace+0xd/0x10
[<c0105656>] dump_stack+0x15/0x17
[<c0132580>] print_circular_bug_tail+0x5a/0x65
[<c0133c44>] __lock_acquire+0x8c6/0xb6f
[<c0133f4e>] lock_acquire+0x61/0x7d
[<c0303006>] __mutex_lock_slowpath+0xbc/0x241
[<c03031a7>] mutex_lock+0x1c/0x1f
[<c0205bbd>] acpi_ec_transaction+0x65/0x1c1
[<c0205d44>] acpi_ec_gpe_query+0x2b/0xab
[<c01e8602>] acpi_os_execute_deferred+0x20/0x31
[<c01268b7>] run_workqueue+0xba/0x182
[<c01271a9>] worker_thread+0xb7/0xc2
[<c01296c4>] kthread+0x39/0x61
[<c0104913>] kernel_thread_helper+0x7/0x10
=======================
On Thu, 9 Aug 2007 16:24:48 -0400
"Miles Lane" <[email protected]> wrote:
> [ INFO: possible circular locking dependency detected ]
> 2.6.23-rc2-mm1 #7
> -------------------------------------------------------
> kacpid/53 is trying to acquire lock:
> (&ec->lock){--..}, at: [<c03031a7>] mutex_lock+0x1c/0x1f
>
> but task is already holding lock:
> (&dpc->work){--..}, at: [<c012689d>] run_workqueue+0xa0/0x182
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #2 (&dpc->work){--..}:
> [<c0133d24>] __lock_acquire+0x9a6/0xb6f
> [<c0133f4e>] lock_acquire+0x61/0x7d
> [<c01268b2>] run_workqueue+0xb5/0x182
> [<c01271a9>] worker_thread+0xb7/0xc2
> [<c01296c4>] kthread+0x39/0x61
> [<c0104913>] kernel_thread_helper+0x7/0x10
> [<ffffffff>] 0xffffffff
>
> -> #1 (kacpid){--..}:
> [<c0133d24>] __lock_acquire+0x9a6/0xb6f
> [<c0133f4e>] lock_acquire+0x61/0x7d
> [<c0126f62>] flush_workqueue+0x2d/0x4f
> [<c01e85e0>] acpi_os_wait_events_complete+0xd/0xf
> [<c01ef605>] acpi_remove_gpe_handler+0x7b/0xdd
> [<c0205981>] ec_remove_handlers+0x26/0x29
> [<c02062b4>] acpi_ec_add+0x8f/0x13e
> [<c0205477>] acpi_device_probe+0x3e/0xdb
> [<c023c4c8>] driver_probe_device+0xd7/0x14d
> [<c023c652>] __driver_attach+0x6a/0xa1
> [<c023baaa>] bus_for_each_dev+0x36/0x5b
> [<c023c32e>] driver_attach+0x14/0x16
> [<c023bd7e>] bus_add_driver+0x70/0x16c
> [<c023c82d>] driver_register+0x60/0x65
> [<c020577b>] acpi_bus_register_driver+0x3a/0x3c
> [<c04292e4>] acpi_ec_init+0x36/0x55
> [<c0416650>] kernel_init+0xc5/0x20f
> [<c0104913>] kernel_thread_helper+0x7/0x10
> [<ffffffff>] 0xffffffff
>
> -> #0 (&ec->lock){--..}:
> [<c0133c44>] __lock_acquire+0x8c6/0xb6f
> [<c0133f4e>] lock_acquire+0x61/0x7d
> [<c0303006>] __mutex_lock_slowpath+0xbc/0x241
> [<c03031a7>] mutex_lock+0x1c/0x1f
> [<c0205bbd>] acpi_ec_transaction+0x65/0x1c1
> [<c0205d44>] acpi_ec_gpe_query+0x2b/0xab
> [<c01e8602>] acpi_os_execute_deferred+0x20/0x31
> [<c01268b7>] run_workqueue+0xba/0x182
> [<c01271a9>] worker_thread+0xb7/0xc2
> [<c01296c4>] kthread+0x39/0x61
> [<c0104913>] kernel_thread_helper+0x7/0x10
> [<ffffffff>] 0xffffffff
>
> other info that might help us debug this:
>
> 2 locks held by kacpid/53:
> #0: (kacpid){--..}, at: [<c0126882>] run_workqueue+0x85/0x182
> #1: (&dpc->work){--..}, at: [<c012689d>] run_workqueue+0xa0/0x182
>
> stack backtrace:
> [<c0104c6a>] show_trace_log_lvl+0x12/0x25
> [<c0105552>] show_trace+0xd/0x10
> [<c0105656>] dump_stack+0x15/0x17
> [<c0132580>] print_circular_bug_tail+0x5a/0x65
> [<c0133c44>] __lock_acquire+0x8c6/0xb6f
> [<c0133f4e>] lock_acquire+0x61/0x7d
> [<c0303006>] __mutex_lock_slowpath+0xbc/0x241
> [<c03031a7>] mutex_lock+0x1c/0x1f
> [<c0205bbd>] acpi_ec_transaction+0x65/0x1c1
> [<c0205d44>] acpi_ec_gpe_query+0x2b/0xab
> [<c01e8602>] acpi_os_execute_deferred+0x20/0x31
> [<c01268b7>] run_workqueue+0xba/0x182
> [<c01271a9>] worker_thread+0xb7/0xc2
> [<c01296c4>] kthread+0x39/0x61
> [<c0104913>] kernel_thread_helper+0x7/0x10
> =======================
Presumably the new debugging patches in -mm
(workqueue-debug-flushing-deadlocks-with-lockdep.patch and
workqueue-debug-work-related-deadlocks-with-lockdep.patch) think they have
found a potential deadlock in ACPI. I don't have time to pick through the
code to confirm that, but boy I'm good at adding cc's ;)
Andrew Morton wrote:
> On Thu, 9 Aug 2007 16:24:48 -0400
> "Miles Lane" <[email protected]> wrote:
>
>> [ INFO: possible circular locking dependency detected ]
>> 2.6.23-rc2-mm1 #7
>> -------------------------------------------------------
>> kacpid/53 is trying to acquire lock:
>> (&ec->lock){--..}, at: [<c03031a7>] mutex_lock+0x1c/0x1f
>>
>> but task is already holding lock:
>> (&dpc->work){--..}, at: [<c012689d>] run_workqueue+0xa0/0x182
>>
>> which lock already depends on the new lock.
>>
>>
>> the existing dependency chain (in reverse order) is:
>>
>> -> #2 (&dpc->work){--..}:
>> [<c0133d24>] __lock_acquire+0x9a6/0xb6f
>> [<c0133f4e>] lock_acquire+0x61/0x7d
>> [<c01268b2>] run_workqueue+0xb5/0x182
>> [<c01271a9>] worker_thread+0xb7/0xc2
>> [<c01296c4>] kthread+0x39/0x61
>> [<c0104913>] kernel_thread_helper+0x7/0x10
>> [<ffffffff>] 0xffffffff
>>
>> -> #1 (kacpid){--..}:
>> [<c0133d24>] __lock_acquire+0x9a6/0xb6f
>> [<c0133f4e>] lock_acquire+0x61/0x7d
>> [<c0126f62>] flush_workqueue+0x2d/0x4f
>> [<c01e85e0>] acpi_os_wait_events_complete+0xd/0xf
>> [<c01ef605>] acpi_remove_gpe_handler+0x7b/0xdd
>> [<c0205981>] ec_remove_handlers+0x26/0x29
>> [<c02062b4>] acpi_ec_add+0x8f/0x13e
>> [<c0205477>] acpi_device_probe+0x3e/0xdb
>> [<c023c4c8>] driver_probe_device+0xd7/0x14d
>> [<c023c652>] __driver_attach+0x6a/0xa1
>> [<c023baaa>] bus_for_each_dev+0x36/0x5b
>> [<c023c32e>] driver_attach+0x14/0x16
>> [<c023bd7e>] bus_add_driver+0x70/0x16c
>> [<c023c82d>] driver_register+0x60/0x65
>> [<c020577b>] acpi_bus_register_driver+0x3a/0x3c
>> [<c04292e4>] acpi_ec_init+0x36/0x55
>> [<c0416650>] kernel_init+0xc5/0x20f
>> [<c0104913>] kernel_thread_helper+0x7/0x10
>> [<ffffffff>] 0xffffffff
>>
>> -> #0 (&ec->lock){--..}:
>> [<c0133c44>] __lock_acquire+0x8c6/0xb6f
>> [<c0133f4e>] lock_acquire+0x61/0x7d
>> [<c0303006>] __mutex_lock_slowpath+0xbc/0x241
>> [<c03031a7>] mutex_lock+0x1c/0x1f
>> [<c0205bbd>] acpi_ec_transaction+0x65/0x1c1
>> [<c0205d44>] acpi_ec_gpe_query+0x2b/0xab
>> [<c01e8602>] acpi_os_execute_deferred+0x20/0x31
>> [<c01268b7>] run_workqueue+0xba/0x182
>> [<c01271a9>] worker_thread+0xb7/0xc2
>> [<c01296c4>] kthread+0x39/0x61
>> [<c0104913>] kernel_thread_helper+0x7/0x10
>> [<ffffffff>] 0xffffffff
>>
>> other info that might help us debug this:
>>
>> 2 locks held by kacpid/53:
>> #0: (kacpid){--..}, at: [<c0126882>] run_workqueue+0x85/0x182
>> #1: (&dpc->work){--..}, at: [<c012689d>] run_workqueue+0xa0/0x182
>>
>> stack backtrace:
>> [<c0104c6a>] show_trace_log_lvl+0x12/0x25
>> [<c0105552>] show_trace+0xd/0x10
>> [<c0105656>] dump_stack+0x15/0x17
>> [<c0132580>] print_circular_bug_tail+0x5a/0x65
>> [<c0133c44>] __lock_acquire+0x8c6/0xb6f
>> [<c0133f4e>] lock_acquire+0x61/0x7d
>> [<c0303006>] __mutex_lock_slowpath+0xbc/0x241
>> [<c03031a7>] mutex_lock+0x1c/0x1f
>> [<c0205bbd>] acpi_ec_transaction+0x65/0x1c1
>> [<c0205d44>] acpi_ec_gpe_query+0x2b/0xab
>> [<c01e8602>] acpi_os_execute_deferred+0x20/0x31
>> [<c01268b7>] run_workqueue+0xba/0x182
>> [<c01271a9>] worker_thread+0xb7/0xc2
>> [<c01296c4>] kthread+0x39/0x61
>> [<c0104913>] kernel_thread_helper+0x7/0x10
>> =======================
>
> Presumably the new debugging patches in -mm
> (workqueue-debug-flushing-deadlocks-with-lockdep.patch and
> workqueue-debug-work-related-deadlocks-with-lockdep.patch) think they have
> found a potential deadlock in ACPI. I don't have time to pick through the
> code to confirm that, but boy I'm good at adding cc's ;)
Yep, it indeed may lock up... Here is a patch to avoid it
Thanks,
Alex.
On Fri, 2007-08-10 at 02:47 +0400, Alexey Starikovskiy wrote:
> > Presumably the new debugging patches in -mm
> > (workqueue-debug-flushing-deadlocks-with-lockdep.patch and
> > workqueue-debug-work-related-deadlocks-with-lockdep.patch) think they have
> > found a potential deadlock in ACPI. I don't have time to pick through the
> > code to confirm that, but boy I'm good at adding cc's ;)
> Yep, it indeed may lock up... Here is a patch to avoid it
Cool. I'm impressed this stuff actually finds something :)
johannes