Bug 197838

Summary: circular locking dependency
Product: [Fedora] Fedora Reporter: Matthias Clasen <mclasen>
Component: kernelAssignee: Kernel Maintainer List <kernel-maint>
Status: CLOSED DUPLICATE QA Contact: Brian Brock <bbrock>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: wtogami
Target Milestone: ---   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2006-07-06 18:56:26 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Matthias Clasen 2006-07-06 18:26:38 UTC
This is with

Jul  6 09:26:54 dhcp83-51 kernel: Linux version 2.6.17-1.2356.fc6
(brewbuilder.redhat.com) (gcc version 4.1.1 20060629 (Red Hat
4.1.1-6)) #1 SMP Thu Jul 6 01:10:48 EDT 2006
J


The /var/log/message entry reads:


Jul  6 09:26:56 dhcp83-51 kernel:
=======================================================
Jul  6 09:26:56 dhcp83-51 kernel: [ INFO: possible circular locking dependency
detected ]
Jul  6 09:26:56 dhcp83-51 kernel:
-------------------------------------------------------
Jul  6 09:26:56 dhcp83-51 kernel: S06cpuspeed/1838 is trying to acquire lock:
Jul  6 09:26:56 dhcp83-51 kernel:  (dbs_mutex){--..}, at: [<c060d6bb>]
mutex_lock+0x21/0x24
Jul  6 09:26:56 dhcp83-51 kernel:
Jul  6 09:26:56 dhcp83-51 kernel: but task is already holding lock:
Jul  6 09:26:56 dhcp83-51 kernel:  (cpucontrol){--..}, at: [<c060d6bb>]
mutex_lock+0x21/0x24
Jul  6 09:26:56 dhcp83-51 kernel:
Jul  6 09:26:56 dhcp83-51 kernel: which lock already depends on the new lock.
Jul  6 09:26:56 dhcp83-51 kernel:
Jul  6 09:26:56 dhcp83-51 kernel:
Jul  6 09:26:56 dhcp83-51 kernel: the existing dependency chain (in reverse
order) is:
Jul  6 09:26:56 dhcp83-51 kernel:
Jul  6 09:26:56 dhcp83-51 kernel: -> #1 (cpucontrol){--..}:
Jul  6 09:26:56 dhcp83-51 kernel:        [<c043c546>] lock_acquire+0x4b/0x6d
Jul  6 09:26:56 dhcp83-51 kernel:        [<c060d51e>]
__mutex_lock_slowpath+0xbf/0x23b
Jul  6 09:26:56 dhcp83-51 kernel:        [<c060d6bb>] mutex_lock+0x21/0x24
Jul  6 09:26:56 dhcp83-51 kernel:        [<c0440009>] __lock_cpu_hotplug+0x36/0x56
Jul  6 09:26:56 dhcp83-51 kernel:        [<c0440042>] lock_cpu_hotplug+0xa/0xc
Jul  6 09:26:56 dhcp83-51 kernel:        [<c04337de>] __create_workqueue+0x52/0x168
Jul  6 09:26:56 dhcp83-51 kernel:        [<f8b9832e>]
cpufreq_governor_dbs+0x9e/0x2cb [cpufreq_ondemand]
Jul  6 09:26:56 dhcp83-51 kernel:        [<c05a724b>] __cpufreq_governor+0x57/0xd8
Jul  6 09:26:56 dhcp83-51 kernel:        [<c05a7409>]
__cpufreq_set_policy+0x13d/0x1a9
Jul  6 09:26:56 dhcp83-51 kernel:        [<c05a760c>]
store_scaling_governor+0x128/0x151

Jul  6 09:26:56 dhcp83-51 kernel:        [<c05a6c67>] store+0x37/0x48
Jul  6 09:26:56 dhcp83-51 kernel:        [<c04ab4cc>] sysfs_write_file+0xab/0xd1
Jul  6 09:26:56 dhcp83-51 kernel:        [<c047248b>] vfs_write+0xab/0x157
Jul  6 09:26:56 dhcp83-51 kernel:        [<c0472ace>] sys_write+0x3b/0x60
Jul  6 09:26:56 dhcp83-51 kernel:        [<c0403f2f>] syscall_call+0x7/0xb
Jul  6 09:26:56 dhcp83-51 kernel:
Jul  6 09:26:56 dhcp83-51 kernel: -> #0 (dbs_mutex){--..}:
Jul  6 09:26:56 dhcp83-51 kernel:        [<c043c546>] lock_acquire+0x4b/0x6d
Jul  6 09:26:56 dhcp83-51 kernel:        [<c060d51e>]
__mutex_lock_slowpath+0xbf/0x23b
Jul  6 09:26:56 dhcp83-51 kernel:        [<c060d6bb>] mutex_lock+0x21/0x24
Jul  6 09:26:56 dhcp83-51 kernel:        [<f8b98503>]
cpufreq_governor_dbs+0x273/0x2cb [cpufreq_ondemand]
Jul  6 09:26:56 dhcp83-51 kernel:        [<c05a724b>] __cpufreq_governor+0x57/0xd8
Jul  6 09:26:56 dhcp83-51 kernel:        [<c05a7463>]
__cpufreq_set_policy+0x197/0x1a9
Jul  6 09:26:56 dhcp83-51 kernel:        [<c05a760c>]
store_scaling_governor+0x128/0x151
Jul  6 09:26:56 dhcp83-51 kernel:        [<c05a6c67>] store+0x37/0x48
Jul  6 09:26:56 dhcp83-51 kernel:        [<c04ab4cc>] sysfs_write_file+0xab/0xd1
Jul  6 09:26:56 dhcp83-51 kernel:        [<c047248b>] vfs_write+0xab/0x157
Jul  6 09:26:56 dhcp83-51 kernel:        [<c0472ace>] sys_write+0x3b/0x60
Jul  6 09:26:56 dhcp83-51 kernel:        [<c0403f2f>] syscall_call+0x7/0xb
Jul  6 09:26:56 dhcp83-51 kernel:
Jul  6 09:26:56 dhcp83-51 kernel: other info that might help us debug this:
Jul  6 09:26:56 dhcp83-51 kernel:
Jul  6 09:26:56 dhcp83-51 kernel: 2 locks held by S06cpuspeed/1838:
Jul  6 09:26:56 dhcp83-51 kernel:  #0:  (&policy->lock){--..}, at: [<c060d6bb>]
mutex_lock+0x21/0x24
Jul  6 09:26:56 dhcp83-51 kernel:  #1:  (cpucontrol){--..}, at: [<c060d6bb>]
mutex_lock+0x21/0x24
Jul  6 09:26:56 dhcp83-51 kernel:
Jul  6 09:26:56 dhcp83-51 kernel: stack backtrace:
Jul  6 09:26:56 dhcp83-51 kernel:  [<c0405167>] show_trace_log_lvl+0x54/0xfd
Jul  6 09:26:56 dhcp83-51 kernel:  [<c040571e>] show_trace+0xd/0x10
Jul  6 09:26:56 dhcp83-51 kernel:  [<c040583d>] dump_stack+0x19/0x1b
Jul  6 09:26:56 dhcp83-51 kernel:  [<c043b63d>] print_circular_bug_tail+0x59/0x64
Jul  6 09:26:56 dhcp83-51 kernel:  [<c043be35>] __lock_acquire+0x7ed/0x98d
Jul  6 09:26:56 dhcp83-51 kernel:  [<c043c546>] lock_acquire+0x4b/0x6d
Jul  6 09:26:56 dhcp83-51 kernel:  [<c060d51e>] __mutex_lock_slowpath+0xbf/0x23b
Jul  6 09:26:56 dhcp83-51 kernel:  [<c060d6bb>] mutex_lock+0x21/0x24
Jul  6 09:26:56 dhcp83-51 kernel:  [<f8b98503>] cpufreq_governor_dbs+0x273/0x2cb
[cpufreq_ondemand]
Jul  6 09:26:56 dhcp83-51 kernel:  [<c05a724b>] __cpufreq_governor+0x57/0xd8
Jul  6 09:26:56 dhcp83-51 kernel:  [<c05a7463>] __cpufreq_set_policy+0x197/0x1a9
Jul  6 09:26:56 dhcp83-51 kernel:  [<c05a760c>] store_scaling_governor+0x128/0x151
Jul  6 09:26:56 dhcp83-51 kernel:  [<c05a6c67>] store+0x37/0x48
Jul  6 09:26:56 dhcp83-51 hcid[2413]: Bluetooth HCI daemon
Jul  6 09:26:56 dhcp83-51 kernel:  [<c04ab4cc>] sysfs_write_file+0xab/0xd1
Jul  6 09:26:56 dhcp83-51 kernel:  [<c047248b>] vfs_write+0xab/0x157
Jul  6 09:26:56 dhcp83-51 kernel:  [<c0472ace>] sys_write+0x3b/0x60

Comment 1 Dave Jones 2006-07-06 18:56:26 UTC

*** This bug has been marked as a duplicate of 197803 ***