[ 1966.343286]
[ 1966.343288] =======================================================
[ 1966.356756] [ INFO: possible circular locking dependency detected ]
[ 1966.356759] 2.6.31-rc1-tip-00978-g99123e5-dirty #438
[ 1966.356761] -------------------------------------------------------
[ 1966.356764] events/0/387 is trying to acquire lock:
[ 1966.356766] (&kvm->lock){+.+.+.}, at: [<ffffffff8100af27>]
kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
[ 1966.356786]
[ 1966.356787] but task is already holding lock:
[ 1966.356789] (&match->interrupt_work){+.+...}, at:
[<ffffffff810986e9>] worker_thread+0x175/0x2f6
[ 1966.356797]
[ 1966.356798] which lock already depends on the new lock.
[ 1966.356799]
[ 1966.356800]
[ 1966.356801] the existing dependency chain (in reverse order) is:
[ 1966.356803]
[ 1966.356803] -> #1 (&match->interrupt_work){+.+...}:
[ 1966.356809] [<ffffffff810b3bf6>] __lock_acquire+0x1396/0x1710
[ 1966.356817] [<ffffffff810b403c>] lock_acquire+0xcc/0x104
[ 1966.356821] [<ffffffff810994a8>] __cancel_work_timer+0x121/0x247
[ 1966.356825] [<ffffffff8109962c>] cancel_work_sync+0x23/0x39
[ 1966.356828] [<ffffffff8100b280>] kvm_deassign_irq+0xf1/0x183
[ 1966.356832] [<ffffffff8100db6c>] kvm_vm_ioctl+0x8c8/0xc1a
[ 1966.356837] [<ffffffff81156e56>] vfs_ioctl+0x3e/0xa3
[ 1966.356846] [<ffffffff8115741c>] do_vfs_ioctl+0x4be/0x511
[ 1966.356850] [<ffffffff811574c5>] sys_ioctl+0x56/0x8d
[ 1966.356854] [<ffffffff81034fdb>] system_call_fastpath+0x16/0x1b
[ 1966.356860] [<ffffffffffffffff>] 0xffffffffffffffff
[ 1966.356869]
[ 1966.356870] -> #0 (&kvm->lock){+.+.+.}:
[ 1966.356872] [<ffffffff810b392b>] __lock_acquire+0x10cb/0x1710
[ 1966.356875] [<ffffffff810b403c>] lock_acquire+0xcc/0x104
[ 1966.356878] [<ffffffff81cde487>] mutex_lock_nested+0x75/0x2fa
[ 1966.356886] [<ffffffff8100af27>]
kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
[ 1966.356890] [<ffffffff81098743>] worker_thread+0x1cf/0x2f6
[ 1966.356892] [<ffffffff8109e335>] kthread+0xa8/0xb0
[ 1966.356899] [<ffffffff8103609a>] child_rip+0xa/0x20
[ 1966.356906] [<ffffffffffffffff>] 0xffffffffffffffff
[ 1966.356908]
[ 1966.356909] other info that might help us debug this:
[ 1966.356909]
[ 1966.356911] 2 locks held by events/0/387:
[ 1966.356913] #0: (events){+.+.+.}, at: [<ffffffff810986e9>]
worker_thread+0x175/0x2f6
[ 1966.356917] #1: (&match->interrupt_work){+.+...}, at:
[<ffffffff810986e9>] worker_thread+0x175/0x2f6
[ 1966.356922]
[ 1966.356923] stack backtrace:
[ 1966.356925] Pid: 387, comm: events/0 Not tainted
2.6.31-rc1-tip-00978-g99123e5-dirty #438
[ 1966.356928] Call Trace:
[ 1966.356932] [<ffffffff810b2362>] print_circular_bug_tail+0xd0/0xef
[ 1966.356935] [<ffffffff810b2232>] ? check_noncircular+0xec/0x14c
[ 1966.356939] [<ffffffff810b392b>] __lock_acquire+0x10cb/0x1710
[ 1966.356942] [<ffffffff8100af27>] ?
kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
[ 1966.356947] [<ffffffff810af6f7>] ? save_trace+0x4e/0xc2
[ 1966.356950] [<ffffffff810b2836>] ? check_irq_usage+0xc6/0xf0
[ 1966.356953] [<ffffffff8100af27>] ?
kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
[ 1966.356956] [<ffffffff810b403c>] lock_acquire+0xcc/0x104
[ 1966.356959] [<ffffffff8100af27>] ?
kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
[ 1966.356962] [<ffffffff810986e9>] ? worker_thread+0x175/0x2f6
[ 1966.356965] [<ffffffff81cde487>] mutex_lock_nested+0x75/0x2fa
[ 1966.356968] [<ffffffff8100af27>] ?
kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
[ 1966.356972] [<ffffffff8100af27>] ?
kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
[ 1966.356975] [<ffffffff810986e9>] ? worker_thread+0x175/0x2f6
[ 1966.356977] [<ffffffff810986e9>] ? worker_thread+0x175/0x2f6
[ 1966.356980] [<ffffffff810986e9>] ? worker_thread+0x175/0x2f6
[ 1966.356983] [<ffffffff8100af27>]
kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
[ 1966.356986] [<ffffffff81098743>] worker_thread+0x1cf/0x2f6
[ 1966.356989] [<ffffffff810986e9>] ? worker_thread+0x175/0x2f6
[ 1966.356992] [<ffffffff8100aee5>] ?
kvm_assigned_dev_interrupt_work_handler+0x0/0x13a
[ 1966.356996] [<ffffffff8109e788>] ? autoremove_wake_function+0x0/0x63
[ 1966.356998] [<ffffffff81098574>] ? worker_thread+0x0/0x2f6
[ 1966.357001] [<ffffffff8109e335>] kthread+0xa8/0xb0
[ 1966.357005] [<ffffffff8103609a>] child_rip+0xa/0x20
[ 1966.357008] [<ffffffff81035a3c>] ? restore_args+0x0/0x30
[ 1966.357011] [<ffffffff8109e28d>] ? kthread+0x0/0xb0
[ 1966.357014] [<ffffffff81036090>] ? child_rip+0x0/0x20
[ 1966.600740] pci-stub 0000:83:00.0: irq 150 for MSI/MSI-X
[ 1966.601061] pci-stub 0000:83:00.0: irq 150 for MSI/MSI-X
On 07/01/2009 07:18 AM, Yinghai Lu wrote:
> [ 1966.343286]
> [ 1966.343288] =======================================================
> [ 1966.356756] [ INFO: possible circular locking dependency detected ]
> [ 1966.356759] 2.6.31-rc1-tip-00978-g99123e5-dirty #438
> [ 1966.356761] -------------------------------------------------------
> [ 1966.356764] events/0/387 is trying to acquire lock:
> [ 1966.356766] (&kvm->lock){+.+.+.}, at: [<ffffffff8100af27>]
> kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
> [ 1966.356786]
> [ 1966.356787] but task is already holding lock:
> [ 1966.356789] (&match->interrupt_work){+.+...}, at:
> [<ffffffff810986e9>] worker_thread+0x175/0x2f6
> [ 1966.356797]
> [ 1966.356798] which lock already depends on the new lock.
> [ 1966.356799]
> [ 1966.356800]
> [ 1966.356801] the existing dependency chain (in reverse order) is:
> [ 1966.356803]
> [ 1966.356803] -> #1 (&match->interrupt_work){+.+...}:
> [ 1966.356809] [<ffffffff810b3bf6>] __lock_acquire+0x1396/0x1710
> [ 1966.356817] [<ffffffff810b403c>] lock_acquire+0xcc/0x104
> [ 1966.356821] [<ffffffff810994a8>] __cancel_work_timer+0x121/0x247
> [ 1966.356825] [<ffffffff8109962c>] cancel_work_sync+0x23/0x39
> [ 1966.356828] [<ffffffff8100b280>] kvm_deassign_irq+0xf1/0x183
> [ 1966.356832] [<ffffffff8100db6c>] kvm_vm_ioctl+0x8c8/0xc1a
> [ 1966.356837] [<ffffffff81156e56>] vfs_ioctl+0x3e/0xa3
> [ 1966.356846] [<ffffffff8115741c>] do_vfs_ioctl+0x4be/0x511
> [ 1966.356850] [<ffffffff811574c5>] sys_ioctl+0x56/0x8d
> [ 1966.356854] [<ffffffff81034fdb>] system_call_fastpath+0x16/0x1b
> [ 1966.356860] [<ffffffffffffffff>] 0xffffffffffffffff
> [ 1966.356869]
> [ 1966.356870] -> #0 (&kvm->lock){+.+.+.}:
> [ 1966.356872] [<ffffffff810b392b>] __lock_acquire+0x10cb/0x1710
> [ 1966.356875] [<ffffffff810b403c>] lock_acquire+0xcc/0x104
> [ 1966.356878] [<ffffffff81cde487>] mutex_lock_nested+0x75/0x2fa
> [ 1966.356886] [<ffffffff8100af27>]
> kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
> [ 1966.356890] [<ffffffff81098743>] worker_thread+0x1cf/0x2f6
> [ 1966.356892] [<ffffffff8109e335>] kthread+0xa8/0xb0
> [ 1966.356899] [<ffffffff8103609a>] child_rip+0xa/0x20
> [ 1966.356906] [<ffffffffffffffff>] 0xffffffffffffffff
>
This is already fixed in kvm.git. I'm not sure about merging it to
2.6.30 since the race is very rare and involves device assignment (which
is not very mainstream), while the fix touches the core kvm parts.
--
error compiling committee.c: too many arguments to function
On Wed, Jul 1, 2009 at 12:49 AM, Avi Kivity<[email protected]> wrote:
> On 07/01/2009 07:18 AM, Yinghai Lu wrote:
>>
>> [ 1966.343286]
>> [ 1966.343288] =======================================================
>> [ 1966.356756] [ INFO: possible circular locking dependency detected ]
>> [ 1966.356759] 2.6.31-rc1-tip-00978-g99123e5-dirty #438
>> [ 1966.356761] -------------------------------------------------------
>> [ 1966.356764] events/0/387 is trying to acquire lock:
>> [ 1966.356766] ?(&kvm->lock){+.+.+.}, at: [<ffffffff8100af27>]
>> kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
>> [ 1966.356786]
>> [ 1966.356787] but task is already holding lock:
>> [ 1966.356789] ?(&match->interrupt_work){+.+...}, at:
>> [<ffffffff810986e9>] worker_thread+0x175/0x2f6
>> [ 1966.356797]
>> [ 1966.356798] which lock already depends on the new lock.
>> [ 1966.356799]
>> [ 1966.356800]
>> [ 1966.356801] the existing dependency chain (in reverse order) is:
>> [ 1966.356803]
>> [ 1966.356803] -> ?#1 (&match->interrupt_work){+.+...}:
>> [ 1966.356809] ? ? ? ?[<ffffffff810b3bf6>] __lock_acquire+0x1396/0x1710
>> [ 1966.356817] ? ? ? ?[<ffffffff810b403c>] lock_acquire+0xcc/0x104
>> [ 1966.356821] ? ? ? ?[<ffffffff810994a8>] __cancel_work_timer+0x121/0x247
>> [ 1966.356825] ? ? ? ?[<ffffffff8109962c>] cancel_work_sync+0x23/0x39
>> [ 1966.356828] ? ? ? ?[<ffffffff8100b280>] kvm_deassign_irq+0xf1/0x183
>> [ 1966.356832] ? ? ? ?[<ffffffff8100db6c>] kvm_vm_ioctl+0x8c8/0xc1a
>> [ 1966.356837] ? ? ? ?[<ffffffff81156e56>] vfs_ioctl+0x3e/0xa3
>> [ 1966.356846] ? ? ? ?[<ffffffff8115741c>] do_vfs_ioctl+0x4be/0x511
>> [ 1966.356850] ? ? ? ?[<ffffffff811574c5>] sys_ioctl+0x56/0x8d
>> [ 1966.356854] ? ? ? ?[<ffffffff81034fdb>] system_call_fastpath+0x16/0x1b
>> [ 1966.356860] ? ? ? ?[<ffffffffffffffff>] 0xffffffffffffffff
>> [ 1966.356869]
>> [ 1966.356870] -> ?#0 (&kvm->lock){+.+.+.}:
>> [ 1966.356872] ? ? ? ?[<ffffffff810b392b>] __lock_acquire+0x10cb/0x1710
>> [ 1966.356875] ? ? ? ?[<ffffffff810b403c>] lock_acquire+0xcc/0x104
>> [ 1966.356878] ? ? ? ?[<ffffffff81cde487>] mutex_lock_nested+0x75/0x2fa
>> [ 1966.356886] ? ? ? ?[<ffffffff8100af27>]
>> kvm_assigned_dev_interrupt_work_handler+0x42/0x13a
>> [ 1966.356890] ? ? ? ?[<ffffffff81098743>] worker_thread+0x1cf/0x2f6
>> [ 1966.356892] ? ? ? ?[<ffffffff8109e335>] kthread+0xa8/0xb0
>> [ 1966.356899] ? ? ? ?[<ffffffff8103609a>] child_rip+0xa/0x20
>> [ 1966.356906] ? ? ? ?[<ffffffffffffffff>] 0xffffffffffffffff
>>
>
> This is already fixed in kvm.git. ?I'm not sure about merging it to 2.6.30
> since the race is very rare and involves device assignment (which is not
> very mainstream), while the fix touches the core kvm parts.
tip/master merged with kvm/master doesn't have that warning.
YH