[libvirt] deadlock while updating VM network filter

[Marcin Gibuła]

Hi,

I've encountered deadlock while updating VM network filter and I'm 
trying to debug it. However I don't have any luck with reproducing it... 
Here's a backtrace of libvirtd daemon. Any hints on how to fix that 
would be appreciated:)

Libvirt version is 1.2.3.

Thread 12 (Thread 0x7fd4550b5700 (LWP 6414)):
#0  0x00007fd4585b5d0c in pthread_cond_wait@@GLIBC_2.3.2 () from 
/lib64/libpthread.so.0
#1  0x00007fd45887e1ba in virCondWait () from /usr/lib64/libvirt.so.0
#2  0x00007fd45887e89b in virThreadPoolWorker () from 
/usr/lib64/libvirt.so.0
#3  0x00007fd45887dcf6 in virThreadHelper () from /usr/lib64/libvirt.so.0
#4  0x00007fd4585b1f3a in start_thread () from /lib64/libpthread.so.0
#5  0x00007fd4582ebdad in clone () from /lib64/libc.so.6

Thread 11 (Thread 0x7fd4548b4700 (LWP 6415)):
#0  0x00007fd4585b87a4 in __lll_lock_wait () from /lib64/libpthread.so.0
#1  0x00007fd4585b419c in _L_lock_518 () from /lib64/libpthread.so.0
#2  0x00007fd4585b3feb in pthread_mutex_lock () from /lib64/libpthread.so.0
#3  0x00007fd4588a96c8 in virDomainListPopulate () from 
/usr/lib64/libvirt.so.0
#4  0x00007fd45884c349 in virHashForEach () from /usr/lib64/libvirt.so.0
#5  0x00007fd4588bc486 in virDomainObjListExport () from 
/usr/lib64/libvirt.so.0
#6  0x00007fd45891b601 in virConnectListAllDomains () from 
/usr/lib64/libvirt.so.0
#7  0x00007fd4593b1d2f in remoteDispatchConnectListAllDomainsHelper ()
#8  0x00007fd4589844d9 in virNetServerProgramDispatch () from 
/usr/lib64/libvirt.so.0
#9  0x00007fd4593dc4ed in virNetServerHandleJob ()
#10 0x00007fd45887e7fe in virThreadPoolWorker () from 
/usr/lib64/libvirt.so.0
#11 0x00007fd45887dcf6 in virThreadHelper () from /usr/lib64/libvirt.so.0
#12 0x00007fd4585b1f3a in start_thread () from /lib64/libpthread.so.0
#13 0x00007fd4582ebdad in clone () from /lib64/libc.so.6

Thread 10 (Thread 0x7fd4540b3700 (LWP 6416)):
#0  0x00007fd4585b87a4 in __lll_lock_wait () from /lib64/libpthread.so.0
#1  0x00007fd4585b41b7 in _L_lock_565 () from /lib64/libpthread.so.0
#2  0x00007fd4585b4049 in pthread_mutex_lock () from /lib64/libpthread.so.0
#3  0x00007fd44cd54100 in virNWFilterLockIface () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_nwfilter.so
#4  0x00007fd44cd47925 in _virNWFilterTeardownFilter () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_nwfilter.so
#5  0x00007fd44cd48910 in virNWFilterTeardownFilter () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_nwfilter.so
#6  0x00007fd44c63d203 in qemuDomainChangeNet () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_qemu.so
#7  0x00007fd44c69b88f in qemuDomainUpdateDeviceFlags () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_qemu.so
#8  0x00007fd458920b2b in virDomainUpdateDeviceFlags () from 
/usr/lib64/libvirt.so.0
#9  0x00007fd4593bc084 in remoteDispatchDomainUpdateDeviceFlagsHelper ()
#10 0x00007fd4589844d9 in virNetServerProgramDispatch () from 
/usr/lib64/libvirt.so.0
#11 0x00007fd4593dc4ed in virNetServerHandleJob ()
#12 0x00007fd45887e7fe in virThreadPoolWorker () from 
/usr/lib64/libvirt.so.0
#13 0x00007fd45887dcf6 in virThreadHelper () from /usr/lib64/libvirt.so.0
#14 0x00007fd4585b1f3a in start_thread () from /lib64/libpthread.so.0
#15 0x00007fd4582ebdad in clone () from /lib64/libc.so.6

Thread 9 (Thread 0x7fd4538b2700 (LWP 6417)):
#0  0x00007fd4585b5d0c in pthread_cond_wait@@GLIBC_2.3.2 () from 
/lib64/libpthread.so.0
#1  0x00007fd45887e1ba in virCondWait () from /usr/lib64/libvirt.so.0
#2  0x00007fd45887e89b in virThreadPoolWorker () from 
/usr/lib64/libvirt.so.0
#3  0x00007fd45887dcf6 in virThreadHelper () from /usr/lib64/libvirt.so.0
#4  0x00007fd4585b1f3a in start_thread () from /lib64/libpthread.so.0
#5  0x00007fd4582ebdad in clone () from /lib64/libc.so.6

Thread 2 (Thread 0x7fd41b7fe700 (LWP 22858)):
#0  0x00007fd4585b87a4 in __lll_lock_wait () from /lib64/libpthread.so.0
#1  0x00007fd4585b41b7 in _L_lock_565 () from /lib64/libpthread.so.0
#2  0x00007fd4585b4049 in pthread_mutex_lock () from /lib64/libpthread.so.0
#3  0x00007fd44cd4873b in virNWFilterInstantiateFilterLate () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_nwfilter.so
#4  0x00007fd44cd54690 in learnIPAddressThread () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_nwfilter.so
#5  0x00007fd4585b1f3a in start_thread () from /lib64/libpthread.so.0
#6  0x00007fd4582ebdad in clone () from /lib64/libc.so.6

Thread 1 (Thread 0x7fd459372740 (LWP 6413)):
#0  0x00007fd4585b87a4 in __lll_lock_wait () from /lib64/libpthread.so.0
#1  0x00007fd4585b419c in _L_lock_518 () from /lib64/libpthread.so.0
#2  0x00007fd4585b3feb in pthread_mutex_lock () from /lib64/libpthread.so.0
#3  0x00007fd44c6452b5 in qemuProcessHandleEvent () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_qemu.so
#4  0x00007fd44c65c50d in qemuMonitorEmitEvent () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_qemu.so
#5  0x00007fd44c66fc73 in qemuMonitorJSONIOProcess () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_qemu.so
#6  0x00007fd44c65ae08 in qemuMonitorIO () from 
/usr/lib64/libvirt/connection-driver/libvirt_driver_qemu.so
#7  0x00007fd4588476a5 in virEventPollRunOnce () from 
/usr/lib64/libvirt.so.0
#8  0x00007fd458845b90 in virEventRunDefaultImpl () from 
/usr/lib64/libvirt.so.0

-- 
mg