* memory-hotplug : possible circular locking dependency detected
@ 2012-09-13 6:19 Yasuaki Ishimatsu
2012-09-14 6:02 ` Wen Congyang
0 siblings, 1 reply; 3+ messages in thread
From: Yasuaki Ishimatsu @ 2012-09-13 6:19 UTC (permalink / raw)
To: linux-kernel, linux-mm, kvm
When I offline a memory on linux-3.6-rc5, "possible circular
locking dependency detected" messages are shown.
Are the messages known problem?
[ 201.596363] Offlined Pages 32768
[ 201.596373] remove from free list 140000 1024 148000
[ 201.596493] remove from free list 140400 1024 148000
[ 201.596612] remove from free list 140800 1024 148000
[ 201.596730] remove from free list 140c00 1024 148000
[ 201.596849] remove from free list 141000 1024 148000
[ 201.596968] remove from free list 141400 1024 148000
[ 201.597049] remove from free list 141800 1024 148000
[ 201.597049] remove from free list 141c00 1024 148000
[ 201.597049] remove from free list 142000 1024 148000
[ 201.597049] remove from free list 142400 1024 148000
[ 201.597049] remove from free list 142800 1024 148000
[ 201.597049] remove from free list 142c00 1024 148000
[ 201.597049] remove from free list 143000 1024 148000
[ 201.597049] remove from free list 143400 1024 148000
[ 201.597049] remove from free list 143800 1024 148000
[ 201.597049] remove from free list 143c00 1024 148000
[ 201.597049] remove from free list 144000 1024 148000
[ 201.597049] remove from free list 144400 1024 148000
[ 201.597049] remove from free list 144800 1024 148000
[ 201.597049] remove from free list 144c00 1024 148000
[ 201.597049] remove from free list 145000 1024 148000
[ 201.597049] remove from free list 145400 1024 148000
[ 201.597049] remove from free list 145800 1024 148000
[ 201.597049] remove from free list 145c00 1024 148000
[ 201.597049] remove from free list 146000 1024 148000
[ 201.597049] remove from free list 146400 1024 148000
[ 201.597049] remove from free list 146800 1024 148000
[ 201.597049] remove from free list 146c00 1024 148000
[ 201.597049] remove from free list 147000 1024 148000
[ 201.597049] remove from free list 147400 1024 148000
[ 201.597049] remove from free list 147800 1024 148000
[ 201.597049] remove from free list 147c00 1024 148000
[ 201.602143]
[ 201.602150] ======================================================
[ 201.602153] [ INFO: possible circular locking dependency detected ]
[ 201.602157] 3.6.0-rc5 #1 Not tainted
[ 201.602159] -------------------------------------------------------
[ 201.602162] bash/2789 is trying to acquire lock:
[ 201.602164] ((memory_chain).rwsem){.+.+.+}, at: [<ffffffff8109fe16>] __blocking_notifier_call_chain+0x66/0xd0
[ 201.602180]
[ 201.602180] but task is already holding lock:
[ 201.602182] (ksm_thread_mutex/1){+.+.+.}, at: [<ffffffff811b41fa>] ksm_memory_callback+0x3a/0xc0
[ 201.602194]
[ 201.602194] which lock already depends on the new lock.
[ 201.602194]
[ 201.602197]
[ 201.602197] the existing dependency chain (in reverse order) is:
[ 201.602200]
[ 201.602200] -> #1 (ksm_thread_mutex/1){+.+.+.}:
[ 201.602208] [<ffffffff810dbee9>] validate_chain+0x6d9/0x7e0
[ 201.602214] [<ffffffff810dc2e6>] __lock_acquire+0x2f6/0x4f0
[ 201.602219] [<ffffffff810dc57d>] lock_acquire+0x9d/0x190
[ 201.602223] [<ffffffff8166b4fc>] __mutex_lock_common+0x5c/0x420
[ 201.602229] [<ffffffff8166ba2a>] mutex_lock_nested+0x4a/0x60
[ 201.602234] [<ffffffff811b41fa>] ksm_memory_callback+0x3a/0xc0
[ 201.602239] [<ffffffff81673447>] notifier_call_chain+0x67/0x150
[ 201.602244] [<ffffffff8109fe2b>] __blocking_notifier_call_chain+0x7b/0xd0
[ 201.602250] [<ffffffff8109fe96>] blocking_notifier_call_chain+0x16/0x20
[ 201.602255] [<ffffffff8144c53b>] memory_notify+0x1b/0x20
[ 201.602261] [<ffffffff81653c51>] offline_pages+0x1b1/0x470
[ 201.602267] [<ffffffff811bfcae>] remove_memory+0x1e/0x20
[ 201.602273] [<ffffffff8144c661>] memory_block_action+0xa1/0x190
[ 201.602278] [<ffffffff8144c7c9>] memory_block_change_state+0x79/0xe0
[ 201.602282] [<ffffffff8144c8f2>] store_mem_state+0xc2/0xd0
[ 201.602287] [<ffffffff81436980>] dev_attr_store+0x20/0x30
[ 201.602293] [<ffffffff812498d3>] sysfs_write_file+0xa3/0x100
[ 201.602299] [<ffffffff811cba80>] vfs_write+0xd0/0x1a0
[ 201.602304] [<ffffffff811cbc54>] sys_write+0x54/0xa0
[ 201.602309] [<ffffffff81678529>] system_call_fastpath+0x16/0x1b
[ 201.602315]
[ 201.602315] -> #0 ((memory_chain).rwsem){.+.+.+}:
[ 201.602322] [<ffffffff810db7e7>] check_prev_add+0x527/0x550
[ 201.602326] [<ffffffff810dbee9>] validate_chain+0x6d9/0x7e0
[ 201.602331] [<ffffffff810dc2e6>] __lock_acquire+0x2f6/0x4f0
[ 201.602335] [<ffffffff810dc57d>] lock_acquire+0x9d/0x190
[ 201.602340] [<ffffffff8166c1a1>] down_read+0x51/0xa0
[ 201.602345] [<ffffffff8109fe16>] __blocking_notifier_call_chain+0x66/0xd0
[ 201.602350] [<ffffffff8109fe96>] blocking_notifier_call_chain+0x16/0x20
[ 201.602355] [<ffffffff8144c53b>] memory_notify+0x1b/0x20
[ 201.602360] [<ffffffff81653e67>] offline_pages+0x3c7/0x470
[ 201.602365] [<ffffffff811bfcae>] remove_memory+0x1e/0x20
[ 201.602370] [<ffffffff8144c661>] memory_block_action+0xa1/0x190
[ 201.602375] [<ffffffff8144c7c9>] memory_block_change_state+0x79/0xe0
[ 201.602379] [<ffffffff8144c8f2>] store_mem_state+0xc2/0xd0
[ 201.602385] [<ffffffff81436980>] dev_attr_store+0x20/0x30
[ 201.602389] [<ffffffff812498d3>] sysfs_write_file+0xa3/0x100
[ 201.602394] [<ffffffff811cba80>] vfs_write+0xd0/0x1a0
[ 201.602398] [<ffffffff811cbc54>] sys_write+0x54/0xa0
[ 201.602403] [<ffffffff81678529>] system_call_fastpath+0x16/0x1b
[ 201.602408]
[ 201.602408] other info that might help us debug this:
[ 201.602408]
[ 201.602412] Possible unsafe locking scenario:
[ 201.602412]
[ 201.602414] CPU0 CPU1
[ 201.602417] ---- ----
[ 201.602419] lock(ksm_thread_mutex/1);
[ 201.602425] lock((memory_chain).rwsem);
[ 201.602430] lock(ksm_thread_mutex/1);
[ 201.602435] lock((memory_chain).rwsem);
[ 201.602440]
[ 201.602440] *** DEADLOCK ***
[ 201.602440]
[ 201.602444] 6 locks held by bash/2789:
[ 201.602446] #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff81249879>] sysfs_write_file+0x49/0x100
[ 201.602456] #1: (s_active#212){.+.+.+}, at: [<ffffffff812498b7>] sysfs_write_file+0x87/0x100
[ 201.602467] #2: (&mem->state_mutex){+.+.+.}, at: [<ffffffff8144c78e>] memory_block_change_state+0x3e/0xe0
[ 201.602477] #3: (mem_hotplug_mutex){+.+.+.}, at: [<ffffffff811bf867>] lock_memory_hotplug+0x17/0x40
[ 201.602487] #4: (pm_mutex){+.+.+.}, at: [<ffffffff811bf885>] lock_memory_hotplug+0x35/0x40
[ 201.602497] #5: (ksm_thread_mutex/1){+.+.+.}, at: [<ffffffff811b41fa>] ksm_memory_callback+0x3a/0xc0
[ 201.602508]
[ 201.602508] stack backtrace:
[ 201.602512] Pid: 2789, comm: bash Not tainted 3.6.0-rc5 #1
[ 201.602515] Call Trace:
[ 201.602522] [<ffffffff810da119>] print_circular_bug+0x109/0x110
[ 201.602527] [<ffffffff810db7e7>] check_prev_add+0x527/0x550
[ 201.602532] [<ffffffff810dbee9>] validate_chain+0x6d9/0x7e0
[ 201.602537] [<ffffffff810dc2e6>] __lock_acquire+0x2f6/0x4f0
[ 201.602543] [<ffffffff8101f7c3>] ? native_sched_clock+0x13/0x80
[ 201.602547] [<ffffffff810dc57d>] lock_acquire+0x9d/0x190
[ 201.602553] [<ffffffff8109fe16>] ? __blocking_notifier_call_chain+0x66/0xd0
[ 201.602558] [<ffffffff8166c1a1>] down_read+0x51/0xa0
[ 201.602563] [<ffffffff8109fe16>] ? __blocking_notifier_call_chain+0x66/0xd0
[ 201.602569] [<ffffffff8109fe16>] __blocking_notifier_call_chain+0x66/0xd0
[ 201.602574] [<ffffffff81186dc6>] ? next_online_pgdat+0x26/0x50
[ 201.602580] [<ffffffff8109fe96>] blocking_notifier_call_chain+0x16/0x20
[ 201.602585] [<ffffffff8144c53b>] memory_notify+0x1b/0x20
[ 201.602590] [<ffffffff81653e67>] offline_pages+0x3c7/0x470
[ 201.602596] [<ffffffff811bfcae>] remove_memory+0x1e/0x20
[ 201.602601] [<ffffffff8144c661>] memory_block_action+0xa1/0x190
[ 201.602606] [<ffffffff8166ba2a>] ? mutex_lock_nested+0x4a/0x60
[ 201.602611] [<ffffffff8144c7c9>] memory_block_change_state+0x79/0xe0
[ 201.602617] [<ffffffff8118f3ec>] ? might_fault+0x5c/0xb0
[ 201.602622] [<ffffffff8144c8f2>] store_mem_state+0xc2/0xd0
[ 201.602627] [<ffffffff812498b7>] ? sysfs_write_file+0x87/0x100
[ 201.602632] [<ffffffff81436980>] dev_attr_store+0x20/0x30
[ 201.602636] [<ffffffff812498d3>] sysfs_write_file+0xa3/0x100
[ 201.602641] [<ffffffff811cba80>] vfs_write+0xd0/0x1a0
[ 201.602646] [<ffffffff811cbc54>] sys_write+0x54/0xa0
[ 201.602652] [<ffffffff81678529>] system_call_fastpath+0x16/0x1b
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: memory-hotplug : possible circular locking dependency detected
2012-09-13 6:19 memory-hotplug : possible circular locking dependency detected Yasuaki Ishimatsu
@ 2012-09-14 6:02 ` Wen Congyang
2012-09-14 6:26 ` Yasuaki Ishimatsu
0 siblings, 1 reply; 3+ messages in thread
From: Wen Congyang @ 2012-09-14 6:02 UTC (permalink / raw)
To: Yasuaki Ishimatsu; +Cc: linux-kernel, linux-mm, kvm
At 09/13/2012 02:19 PM, Yasuaki Ishimatsu Wrote:
> When I offline a memory on linux-3.6-rc5, "possible circular
> locking dependency detected" messages are shown.
> Are the messages known problem?
It is a known problem, but it doesn't cause a deadlock.
There is 3 locks: memory hotplug's lock, memory hotplug
notifier's lock, and ksm_thread_mutex.
ksm_thread_mutex is locked when the memory is going offline
and is unlocked when the memory is offlined or the offlining
is cancelled. So we meet the warning messages. But it
doesn't cause deadlock, because we lock mem_hotplug_mutex
first.
Thanks
Wen Congyang
>
> [ 201.596363] Offlined Pages 32768
> [ 201.596373] remove from free list 140000 1024 148000
> [ 201.596493] remove from free list 140400 1024 148000
> [ 201.596612] remove from free list 140800 1024 148000
> [ 201.596730] remove from free list 140c00 1024 148000
> [ 201.596849] remove from free list 141000 1024 148000
> [ 201.596968] remove from free list 141400 1024 148000
> [ 201.597049] remove from free list 141800 1024 148000
> [ 201.597049] remove from free list 141c00 1024 148000
> [ 201.597049] remove from free list 142000 1024 148000
> [ 201.597049] remove from free list 142400 1024 148000
> [ 201.597049] remove from free list 142800 1024 148000
> [ 201.597049] remove from free list 142c00 1024 148000
> [ 201.597049] remove from free list 143000 1024 148000
> [ 201.597049] remove from free list 143400 1024 148000
> [ 201.597049] remove from free list 143800 1024 148000
> [ 201.597049] remove from free list 143c00 1024 148000
> [ 201.597049] remove from free list 144000 1024 148000
> [ 201.597049] remove from free list 144400 1024 148000
> [ 201.597049] remove from free list 144800 1024 148000
> [ 201.597049] remove from free list 144c00 1024 148000
> [ 201.597049] remove from free list 145000 1024 148000
> [ 201.597049] remove from free list 145400 1024 148000
> [ 201.597049] remove from free list 145800 1024 148000
> [ 201.597049] remove from free list 145c00 1024 148000
> [ 201.597049] remove from free list 146000 1024 148000
> [ 201.597049] remove from free list 146400 1024 148000
> [ 201.597049] remove from free list 146800 1024 148000
> [ 201.597049] remove from free list 146c00 1024 148000
> [ 201.597049] remove from free list 147000 1024 148000
> [ 201.597049] remove from free list 147400 1024 148000
> [ 201.597049] remove from free list 147800 1024 148000
> [ 201.597049] remove from free list 147c00 1024 148000
> [ 201.602143]
> [ 201.602150] ======================================================
> [ 201.602153] [ INFO: possible circular locking dependency detected ]
> [ 201.602157] 3.6.0-rc5 #1 Not tainted
> [ 201.602159] -------------------------------------------------------
> [ 201.602162] bash/2789 is trying to acquire lock:
> [ 201.602164] ((memory_chain).rwsem){.+.+.+}, at: [<ffffffff8109fe16>] __blocking_notifier_call_chain+0x66/0xd0
> [ 201.602180]
> [ 201.602180] but task is already holding lock:
> [ 201.602182] (ksm_thread_mutex/1){+.+.+.}, at: [<ffffffff811b41fa>] ksm_memory_callback+0x3a/0xc0
> [ 201.602194]
> [ 201.602194] which lock already depends on the new lock.
> [ 201.602194]
> [ 201.602197]
> [ 201.602197] the existing dependency chain (in reverse order) is:
> [ 201.602200]
> [ 201.602200] -> #1 (ksm_thread_mutex/1){+.+.+.}:
> [ 201.602208] [<ffffffff810dbee9>] validate_chain+0x6d9/0x7e0
> [ 201.602214] [<ffffffff810dc2e6>] __lock_acquire+0x2f6/0x4f0
> [ 201.602219] [<ffffffff810dc57d>] lock_acquire+0x9d/0x190
> [ 201.602223] [<ffffffff8166b4fc>] __mutex_lock_common+0x5c/0x420
> [ 201.602229] [<ffffffff8166ba2a>] mutex_lock_nested+0x4a/0x60
> [ 201.602234] [<ffffffff811b41fa>] ksm_memory_callback+0x3a/0xc0
> [ 201.602239] [<ffffffff81673447>] notifier_call_chain+0x67/0x150
> [ 201.602244] [<ffffffff8109fe2b>] __blocking_notifier_call_chain+0x7b/0xd0
> [ 201.602250] [<ffffffff8109fe96>] blocking_notifier_call_chain+0x16/0x20
> [ 201.602255] [<ffffffff8144c53b>] memory_notify+0x1b/0x20
> [ 201.602261] [<ffffffff81653c51>] offline_pages+0x1b1/0x470
> [ 201.602267] [<ffffffff811bfcae>] remove_memory+0x1e/0x20
> [ 201.602273] [<ffffffff8144c661>] memory_block_action+0xa1/0x190
> [ 201.602278] [<ffffffff8144c7c9>] memory_block_change_state+0x79/0xe0
> [ 201.602282] [<ffffffff8144c8f2>] store_mem_state+0xc2/0xd0
> [ 201.602287] [<ffffffff81436980>] dev_attr_store+0x20/0x30
> [ 201.602293] [<ffffffff812498d3>] sysfs_write_file+0xa3/0x100
> [ 201.602299] [<ffffffff811cba80>] vfs_write+0xd0/0x1a0
> [ 201.602304] [<ffffffff811cbc54>] sys_write+0x54/0xa0
> [ 201.602309] [<ffffffff81678529>] system_call_fastpath+0x16/0x1b
> [ 201.602315]
> [ 201.602315] -> #0 ((memory_chain).rwsem){.+.+.+}:
> [ 201.602322] [<ffffffff810db7e7>] check_prev_add+0x527/0x550
> [ 201.602326] [<ffffffff810dbee9>] validate_chain+0x6d9/0x7e0
> [ 201.602331] [<ffffffff810dc2e6>] __lock_acquire+0x2f6/0x4f0
> [ 201.602335] [<ffffffff810dc57d>] lock_acquire+0x9d/0x190
> [ 201.602340] [<ffffffff8166c1a1>] down_read+0x51/0xa0
> [ 201.602345] [<ffffffff8109fe16>] __blocking_notifier_call_chain+0x66/0xd0
> [ 201.602350] [<ffffffff8109fe96>] blocking_notifier_call_chain+0x16/0x20
> [ 201.602355] [<ffffffff8144c53b>] memory_notify+0x1b/0x20
> [ 201.602360] [<ffffffff81653e67>] offline_pages+0x3c7/0x470
> [ 201.602365] [<ffffffff811bfcae>] remove_memory+0x1e/0x20
> [ 201.602370] [<ffffffff8144c661>] memory_block_action+0xa1/0x190
> [ 201.602375] [<ffffffff8144c7c9>] memory_block_change_state+0x79/0xe0
> [ 201.602379] [<ffffffff8144c8f2>] store_mem_state+0xc2/0xd0
> [ 201.602385] [<ffffffff81436980>] dev_attr_store+0x20/0x30
> [ 201.602389] [<ffffffff812498d3>] sysfs_write_file+0xa3/0x100
> [ 201.602394] [<ffffffff811cba80>] vfs_write+0xd0/0x1a0
> [ 201.602398] [<ffffffff811cbc54>] sys_write+0x54/0xa0
> [ 201.602403] [<ffffffff81678529>] system_call_fastpath+0x16/0x1b
> [ 201.602408]
> [ 201.602408] other info that might help us debug this:
> [ 201.602408]
> [ 201.602412] Possible unsafe locking scenario:
> [ 201.602412]
> [ 201.602414] CPU0 CPU1
> [ 201.602417] ---- ----
> [ 201.602419] lock(ksm_thread_mutex/1);
> [ 201.602425] lock((memory_chain).rwsem);
> [ 201.602430] lock(ksm_thread_mutex/1);
> [ 201.602435] lock((memory_chain).rwsem);
> [ 201.602440]
> [ 201.602440] *** DEADLOCK ***
> [ 201.602440]
> [ 201.602444] 6 locks held by bash/2789:
> [ 201.602446] #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff81249879>] sysfs_write_file+0x49/0x100
> [ 201.602456] #1: (s_active#212){.+.+.+}, at: [<ffffffff812498b7>] sysfs_write_file+0x87/0x100
> [ 201.602467] #2: (&mem->state_mutex){+.+.+.}, at: [<ffffffff8144c78e>] memory_block_change_state+0x3e/0xe0
> [ 201.602477] #3: (mem_hotplug_mutex){+.+.+.}, at: [<ffffffff811bf867>] lock_memory_hotplug+0x17/0x40
> [ 201.602487] #4: (pm_mutex){+.+.+.}, at: [<ffffffff811bf885>] lock_memory_hotplug+0x35/0x40
> [ 201.602497] #5: (ksm_thread_mutex/1){+.+.+.}, at: [<ffffffff811b41fa>] ksm_memory_callback+0x3a/0xc0
> [ 201.602508]
> [ 201.602508] stack backtrace:
> [ 201.602512] Pid: 2789, comm: bash Not tainted 3.6.0-rc5 #1
> [ 201.602515] Call Trace:
> [ 201.602522] [<ffffffff810da119>] print_circular_bug+0x109/0x110
> [ 201.602527] [<ffffffff810db7e7>] check_prev_add+0x527/0x550
> [ 201.602532] [<ffffffff810dbee9>] validate_chain+0x6d9/0x7e0
> [ 201.602537] [<ffffffff810dc2e6>] __lock_acquire+0x2f6/0x4f0
> [ 201.602543] [<ffffffff8101f7c3>] ? native_sched_clock+0x13/0x80
> [ 201.602547] [<ffffffff810dc57d>] lock_acquire+0x9d/0x190
> [ 201.602553] [<ffffffff8109fe16>] ? __blocking_notifier_call_chain+0x66/0xd0
> [ 201.602558] [<ffffffff8166c1a1>] down_read+0x51/0xa0
> [ 201.602563] [<ffffffff8109fe16>] ? __blocking_notifier_call_chain+0x66/0xd0
> [ 201.602569] [<ffffffff8109fe16>] __blocking_notifier_call_chain+0x66/0xd0
> [ 201.602574] [<ffffffff81186dc6>] ? next_online_pgdat+0x26/0x50
> [ 201.602580] [<ffffffff8109fe96>] blocking_notifier_call_chain+0x16/0x20
> [ 201.602585] [<ffffffff8144c53b>] memory_notify+0x1b/0x20
> [ 201.602590] [<ffffffff81653e67>] offline_pages+0x3c7/0x470
> [ 201.602596] [<ffffffff811bfcae>] remove_memory+0x1e/0x20
> [ 201.602601] [<ffffffff8144c661>] memory_block_action+0xa1/0x190
> [ 201.602606] [<ffffffff8166ba2a>] ? mutex_lock_nested+0x4a/0x60
> [ 201.602611] [<ffffffff8144c7c9>] memory_block_change_state+0x79/0xe0
> [ 201.602617] [<ffffffff8118f3ec>] ? might_fault+0x5c/0xb0
> [ 201.602622] [<ffffffff8144c8f2>] store_mem_state+0xc2/0xd0
> [ 201.602627] [<ffffffff812498b7>] ? sysfs_write_file+0x87/0x100
> [ 201.602632] [<ffffffff81436980>] dev_attr_store+0x20/0x30
> [ 201.602636] [<ffffffff812498d3>] sysfs_write_file+0xa3/0x100
> [ 201.602641] [<ffffffff811cba80>] vfs_write+0xd0/0x1a0
> [ 201.602646] [<ffffffff811cbc54>] sys_write+0x54/0xa0
> [ 201.602652] [<ffffffff81678529>] system_call_fastpath+0x16/0x1b
>
> --
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^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: memory-hotplug : possible circular locking dependency detected
2012-09-14 6:02 ` Wen Congyang
@ 2012-09-14 6:26 ` Yasuaki Ishimatsu
0 siblings, 0 replies; 3+ messages in thread
From: Yasuaki Ishimatsu @ 2012-09-14 6:26 UTC (permalink / raw)
To: Wen Congyang; +Cc: linux-kernel, linux-mm, kvm
Hi Wen,
2012/09/14 15:02, Wen Congyang wrote:
> At 09/13/2012 02:19 PM, Yasuaki Ishimatsu Wrote:
>> When I offline a memory on linux-3.6-rc5, "possible circular
>> locking dependency detected" messages are shown.
>> Are the messages known problem?
>
> It is a known problem, but it doesn't cause a deadlock.
> There is 3 locks: memory hotplug's lock, memory hotplug
> notifier's lock, and ksm_thread_mutex.
>
> ksm_thread_mutex is locked when the memory is going offline
> and is unlocked when the memory is offlined or the offlining
> is cancelled. So we meet the warning messages. But it
> doesn't cause deadlock, because we lock mem_hotplug_mutex
> first.
Thank you for your clarification.
I understand it. So I ignore the messages.
Thanks,
Yasuaki Ishimatsu
>
> Thanks
> Wen Congyang
>
>>
>> [ 201.596363] Offlined Pages 32768
>> [ 201.596373] remove from free list 140000 1024 148000
>> [ 201.596493] remove from free list 140400 1024 148000
>> [ 201.596612] remove from free list 140800 1024 148000
>> [ 201.596730] remove from free list 140c00 1024 148000
>> [ 201.596849] remove from free list 141000 1024 148000
>> [ 201.596968] remove from free list 141400 1024 148000
>> [ 201.597049] remove from free list 141800 1024 148000
>> [ 201.597049] remove from free list 141c00 1024 148000
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>> [ 201.602143]
>> [ 201.602150] ======================================================
>> [ 201.602153] [ INFO: possible circular locking dependency detected ]
>> [ 201.602157] 3.6.0-rc5 #1 Not tainted
>> [ 201.602159] -------------------------------------------------------
>> [ 201.602162] bash/2789 is trying to acquire lock:
>> [ 201.602164] ((memory_chain).rwsem){.+.+.+}, at: [<ffffffff8109fe16>] __blocking_notifier_call_chain+0x66/0xd0
>> [ 201.602180]
>> [ 201.602180] but task is already holding lock:
>> [ 201.602182] (ksm_thread_mutex/1){+.+.+.}, at: [<ffffffff811b41fa>] ksm_memory_callback+0x3a/0xc0
>> [ 201.602194]
>> [ 201.602194] which lock already depends on the new lock.
>> [ 201.602194]
>> [ 201.602197]
>> [ 201.602197] the existing dependency chain (in reverse order) is:
>> [ 201.602200]
>> [ 201.602200] -> #1 (ksm_thread_mutex/1){+.+.+.}:
>> [ 201.602208] [<ffffffff810dbee9>] validate_chain+0x6d9/0x7e0
>> [ 201.602214] [<ffffffff810dc2e6>] __lock_acquire+0x2f6/0x4f0
>> [ 201.602219] [<ffffffff810dc57d>] lock_acquire+0x9d/0x190
>> [ 201.602223] [<ffffffff8166b4fc>] __mutex_lock_common+0x5c/0x420
>> [ 201.602229] [<ffffffff8166ba2a>] mutex_lock_nested+0x4a/0x60
>> [ 201.602234] [<ffffffff811b41fa>] ksm_memory_callback+0x3a/0xc0
>> [ 201.602239] [<ffffffff81673447>] notifier_call_chain+0x67/0x150
>> [ 201.602244] [<ffffffff8109fe2b>] __blocking_notifier_call_chain+0x7b/0xd0
>> [ 201.602250] [<ffffffff8109fe96>] blocking_notifier_call_chain+0x16/0x20
>> [ 201.602255] [<ffffffff8144c53b>] memory_notify+0x1b/0x20
>> [ 201.602261] [<ffffffff81653c51>] offline_pages+0x1b1/0x470
>> [ 201.602267] [<ffffffff811bfcae>] remove_memory+0x1e/0x20
>> [ 201.602273] [<ffffffff8144c661>] memory_block_action+0xa1/0x190
>> [ 201.602278] [<ffffffff8144c7c9>] memory_block_change_state+0x79/0xe0
>> [ 201.602282] [<ffffffff8144c8f2>] store_mem_state+0xc2/0xd0
>> [ 201.602287] [<ffffffff81436980>] dev_attr_store+0x20/0x30
>> [ 201.602293] [<ffffffff812498d3>] sysfs_write_file+0xa3/0x100
>> [ 201.602299] [<ffffffff811cba80>] vfs_write+0xd0/0x1a0
>> [ 201.602304] [<ffffffff811cbc54>] sys_write+0x54/0xa0
>> [ 201.602309] [<ffffffff81678529>] system_call_fastpath+0x16/0x1b
>> [ 201.602315]
>> [ 201.602315] -> #0 ((memory_chain).rwsem){.+.+.+}:
>> [ 201.602322] [<ffffffff810db7e7>] check_prev_add+0x527/0x550
>> [ 201.602326] [<ffffffff810dbee9>] validate_chain+0x6d9/0x7e0
>> [ 201.602331] [<ffffffff810dc2e6>] __lock_acquire+0x2f6/0x4f0
>> [ 201.602335] [<ffffffff810dc57d>] lock_acquire+0x9d/0x190
>> [ 201.602340] [<ffffffff8166c1a1>] down_read+0x51/0xa0
>> [ 201.602345] [<ffffffff8109fe16>] __blocking_notifier_call_chain+0x66/0xd0
>> [ 201.602350] [<ffffffff8109fe96>] blocking_notifier_call_chain+0x16/0x20
>> [ 201.602355] [<ffffffff8144c53b>] memory_notify+0x1b/0x20
>> [ 201.602360] [<ffffffff81653e67>] offline_pages+0x3c7/0x470
>> [ 201.602365] [<ffffffff811bfcae>] remove_memory+0x1e/0x20
>> [ 201.602370] [<ffffffff8144c661>] memory_block_action+0xa1/0x190
>> [ 201.602375] [<ffffffff8144c7c9>] memory_block_change_state+0x79/0xe0
>> [ 201.602379] [<ffffffff8144c8f2>] store_mem_state+0xc2/0xd0
>> [ 201.602385] [<ffffffff81436980>] dev_attr_store+0x20/0x30
>> [ 201.602389] [<ffffffff812498d3>] sysfs_write_file+0xa3/0x100
>> [ 201.602394] [<ffffffff811cba80>] vfs_write+0xd0/0x1a0
>> [ 201.602398] [<ffffffff811cbc54>] sys_write+0x54/0xa0
>> [ 201.602403] [<ffffffff81678529>] system_call_fastpath+0x16/0x1b
>> [ 201.602408]
>> [ 201.602408] other info that might help us debug this:
>> [ 201.602408]
>> [ 201.602412] Possible unsafe locking scenario:
>> [ 201.602412]
>> [ 201.602414] CPU0 CPU1
>> [ 201.602417] ---- ----
>> [ 201.602419] lock(ksm_thread_mutex/1);
>> [ 201.602425] lock((memory_chain).rwsem);
>> [ 201.602430] lock(ksm_thread_mutex/1);
>> [ 201.602435] lock((memory_chain).rwsem);
>> [ 201.602440]
>> [ 201.602440] *** DEADLOCK ***
>> [ 201.602440]
>> [ 201.602444] 6 locks held by bash/2789:
>> [ 201.602446] #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff81249879>] sysfs_write_file+0x49/0x100
>> [ 201.602456] #1: (s_active#212){.+.+.+}, at: [<ffffffff812498b7>] sysfs_write_file+0x87/0x100
>> [ 201.602467] #2: (&mem->state_mutex){+.+.+.}, at: [<ffffffff8144c78e>] memory_block_change_state+0x3e/0xe0
>> [ 201.602477] #3: (mem_hotplug_mutex){+.+.+.}, at: [<ffffffff811bf867>] lock_memory_hotplug+0x17/0x40
>> [ 201.602487] #4: (pm_mutex){+.+.+.}, at: [<ffffffff811bf885>] lock_memory_hotplug+0x35/0x40
>> [ 201.602497] #5: (ksm_thread_mutex/1){+.+.+.}, at: [<ffffffff811b41fa>] ksm_memory_callback+0x3a/0xc0
>> [ 201.602508]
>> [ 201.602508] stack backtrace:
>> [ 201.602512] Pid: 2789, comm: bash Not tainted 3.6.0-rc5 #1
>> [ 201.602515] Call Trace:
>> [ 201.602522] [<ffffffff810da119>] print_circular_bug+0x109/0x110
>> [ 201.602527] [<ffffffff810db7e7>] check_prev_add+0x527/0x550
>> [ 201.602532] [<ffffffff810dbee9>] validate_chain+0x6d9/0x7e0
>> [ 201.602537] [<ffffffff810dc2e6>] __lock_acquire+0x2f6/0x4f0
>> [ 201.602543] [<ffffffff8101f7c3>] ? native_sched_clock+0x13/0x80
>> [ 201.602547] [<ffffffff810dc57d>] lock_acquire+0x9d/0x190
>> [ 201.602553] [<ffffffff8109fe16>] ? __blocking_notifier_call_chain+0x66/0xd0
>> [ 201.602558] [<ffffffff8166c1a1>] down_read+0x51/0xa0
>> [ 201.602563] [<ffffffff8109fe16>] ? __blocking_notifier_call_chain+0x66/0xd0
>> [ 201.602569] [<ffffffff8109fe16>] __blocking_notifier_call_chain+0x66/0xd0
>> [ 201.602574] [<ffffffff81186dc6>] ? next_online_pgdat+0x26/0x50
>> [ 201.602580] [<ffffffff8109fe96>] blocking_notifier_call_chain+0x16/0x20
>> [ 201.602585] [<ffffffff8144c53b>] memory_notify+0x1b/0x20
>> [ 201.602590] [<ffffffff81653e67>] offline_pages+0x3c7/0x470
>> [ 201.602596] [<ffffffff811bfcae>] remove_memory+0x1e/0x20
>> [ 201.602601] [<ffffffff8144c661>] memory_block_action+0xa1/0x190
>> [ 201.602606] [<ffffffff8166ba2a>] ? mutex_lock_nested+0x4a/0x60
>> [ 201.602611] [<ffffffff8144c7c9>] memory_block_change_state+0x79/0xe0
>> [ 201.602617] [<ffffffff8118f3ec>] ? might_fault+0x5c/0xb0
>> [ 201.602622] [<ffffffff8144c8f2>] store_mem_state+0xc2/0xd0
>> [ 201.602627] [<ffffffff812498b7>] ? sysfs_write_file+0x87/0x100
>> [ 201.602632] [<ffffffff81436980>] dev_attr_store+0x20/0x30
>> [ 201.602636] [<ffffffff812498d3>] sysfs_write_file+0xa3/0x100
>> [ 201.602641] [<ffffffff811cba80>] vfs_write+0xd0/0x1a0
>> [ 201.602646] [<ffffffff811cbc54>] sys_write+0x54/0xa0
>> [ 201.602652] [<ffffffff81678529>] system_call_fastpath+0x16/0x1b
>>
>> --
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>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2012-09-14 6:27 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2012-09-13 6:19 memory-hotplug : possible circular locking dependency detected Yasuaki Ishimatsu
2012-09-14 6:02 ` Wen Congyang
2012-09-14 6:26 ` Yasuaki Ishimatsu
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