(gdb) thread apply all bt

Thread 6 (Thread 0x7f67f32c1700 (LWP 9341)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f67f6fc4a87 in gst_task_func (task=0xa0b040) at gsttask.c:312
#2  0x00007f67f611b73f in g_thread_pool_thread_proxy (data=<value optimised out>)
    at /build/buildd/glib2.0-2.26.1/glib/gthreadpool.c:319
#3  0x00007f67f61197e4 in g_thread_create_proxy (data=0x9c04f0)
    at /build/buildd/glib2.0-2.26.1/glib/gthread.c:1897
#4  0x00007f67f5e9a971 in start_thread (arg=<value optimised out>) at pthread_create.c:304
#5  0x00007f67f5bf692d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#6  0x0000000000000000 in ?? ()

Thread 5 (Thread 0x7f67f2ac0700 (LWP 9342)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f67f7265743 in gst_data_queue_pop (queue=0xa0c9a0, item=0x7f67f2abfd48) at gstdataqueue.c:502
#2  0x00007f67f40a076c in gst_multi_queue_loop (pad=<value optimised out>) at gstmultiqueue.c:1200
#3  0x00007f67f6fc48dd in gst_task_func (task=0xa0b640) at gsttask.c:327
#4  0x00007f67f611b73f in g_thread_pool_thread_proxy (data=<value optimised out>)
    at /build/buildd/glib2.0-2.26.1/glib/gthreadpool.c:319
#5  0x00007f67f61197e4 in g_thread_create_proxy (data=0xa097a0)
    at /build/buildd/glib2.0-2.26.1/glib/gthread.c:1897
#6  0x00007f67f5e9a971 in start_thread (arg=<value optimised out>) at pthread_create.c:304
#7  0x00007f67f5bf692d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#8  0x0000000000000000 in ?? ()

Thread 4 (Thread 0x7f67f1c7d700 (LWP 9343)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f67f6fc4a87 in gst_task_func (task=0xa0b740) at gsttask.c:312
#2  0x00007f67f611b73f in g_thread_pool_thread_proxy (data=<value optimised out>)
    at /build/buildd/glib2.0-2.26.1/glib/gthreadpool.c:319
#3  0x00007f67f61197e4 in g_thread_create_proxy (data=0xa19980)
    at /build/buildd/glib2.0-2.26.1/glib/gthread.c:1897
#4  0x00007f67f5e9a971 in start_thread (arg=<value optimised out>) at pthread_create.c:304
#5  0x00007f67f5bf692d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#6  0x0000000000000000 in ?? ()

Thread 3 (Thread 0x7f67f0e1d700 (LWP 9344)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f67f6f93776 in handle_pad_block (pad=0xa8aa80) at gstpad.c:4100
#2  0x00007f67f6f988b0 in gst_pad_alloc_buffer_full (pad=0xa8aa80, offset=<value optimised out>, size=36864, 
    caps=<value optimised out>, buf=0x7f67f0e1c508, setcaps=<value optimised out>) at gstpad.c:3090
#3  0x00007f67eb5fbd20 in gst_a52dec_handle_frame (bdec=0xa878b0, buffer=<value optimised out>)
    at gsta52dec.c:622
#4  0x00007f67f10453ce in gst_audio_decoder_push_buffers (dec=0xa878b0, force=<value optimised out>)
    at gstaudiodecoder.c:1028
#5  0x00007f67f10457d0 in gst_audio_decoder_chain_forward (dec=0xa878b0, buffer=0x7f67ec019a80)
    at gstaudiodecoder.c:1130
#6  0x00007f67f104659e in gst_audio_decoder_chain (pad=<value optimised out>, buffer=0x7f67ec019a80)
    at gstaudiodecoder.c:1375
#7  0x00007f67f6f96900 in gst_pad_chain_data_unchecked (pad=0xa8a900, is_buffer=1, data=0x7f67ec019a80, 
    cache=0x7f67f0e1c7d0) at gstpad.c:4271
#8  0x00007f67f6f97207 in gst_pad_push_data (pad=0x7f67ec023350, is_buffer=1, data=0x7f67ec019a80, 
    cache=<value optimised out>) at gstpad.c:4506
#9  0x00007f67f6f9e98d in gst_pad_push (pad=0x7f67ec023350, buffer=0x7f67ec019a80) at gstpad.c:4730
#10 0x00007f67f7256cb9 in gst_base_transform_chain (pad=<value optimised out>, buffer=<value optimised out>)
    at gstbasetransform.c:2687
#11 0x00007f67f6f96900 in gst_pad_chain_data_unchecked (pad=0x7f67ec0231d0, is_buffer=1, 
    data=0x7f67ec019a80, cache=0x7f67f0e1c980) at gstpad.c:4271
#12 0x00007f67f6f97207 in gst_pad_push_data (pad=0x7f67ec023050, is_buffer=1, data=0x7f67ec019a80, 
    cache=<value optimised out>) at gstpad.c:4506
#13 0x00007f67f6f9e98d in gst_pad_push (pad=0x7f67ec023050, buffer=0x7f67ec019a80) at gstpad.c:4730
#14 0x00007f67f72334ee in gst_base_parse_push_frame (parse=0x7f67ec022600, frame=0x7f67ec022a10)
    at gstbaseparse.c:1993
#15 0x00007f67f7237dbe in gst_base_parse_handle_and_push_frame (parse=0x7f67ec022600, 
    klass=<value optimised out>, frame=0x7f67ec022a10) at gstbaseparse.c:1770
#16 0x00007f67f7238e6d in gst_base_parse_chain (pad=<value optimised out>, buffer=<value optimised out>)
    at gstbaseparse.c:2493
#17 0x00007f67f6f9ea9c in gst_pad_push (pad=0xa16ca0, buffer=0x7f67ec02e8a0) at gstpad.c:4710
#18 0x00007f67f40a10a2 in gst_single_queue_push_one (pad=<value optimised out>) at gstmultiqueue.c:1087
#19 gst_multi_queue_loop (pad=<value optimised out>) at gstmultiqueue.c:1318
#20 0x00007f67f6fc48dd in gst_task_func (task=0xa0b840) at gsttask.c:327
#21 0x00007f67f611b73f in g_thread_pool_thread_proxy (data=<value optimised out>)
    at /build/buildd/glib2.0-2.26.1/glib/gthreadpool.c:319
#22 0x00007f67f61197e4 in g_thread_create_proxy (data=0x7f67ec01fa10)
    at /build/buildd/glib2.0-2.26.1/glib/gthread.c:1897
#23 0x00007f67f5e9a971 in start_thread (arg=<value optimised out>) at pthread_create.c:304
#24 0x00007f67f5bf692d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#25 0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f67ebfff700 (LWP 9345)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f67f7265743 in gst_data_queue_pop (queue=0xa12bc0, item=0x7f67ebffed48) at gstdataqueue.c:502
#2  0x00007f67f40a076c in gst_multi_queue_loop (pad=<value optimised out>) at gstmultiqueue.c:1200
#3  0x00007f67f6fc48dd in gst_task_func (task=0xa0b940) at gsttask.c:327
#4  0x00007f67f611b73f in g_thread_pool_thread_proxy (data=<value optimised out>)
    at /build/buildd/glib2.0-2.26.1/glib/gthreadpool.c:319
#5  0x00007f67f61197e4 in g_thread_create_proxy (data=0x7f67ec026360)
    at /build/buildd/glib2.0-2.26.1/glib/gthread.c:1897
#6  0x00007f67f5e9a971 in start_thread (arg=<value optimised out>) at pthread_create.c:304
#7  0x00007f67f5bf692d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#8  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f67f7aa8700 (LWP 9340)):
#0  __lll_lock_wait () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:136
#1  0x00007f67f5e9c849 in _L_lock_953 () from /lib/libpthread.so.0
#2  0x00007f67f5e9c66b in __pthread_mutex_lock (mutex=0xa1d188) at pthread_mutex_lock.c:61
#3  0x00007f67f611a30c in g_static_rec_mutex_lock (mutex=0xa1d180)
    at /build/buildd/glib2.0-2.26.1/glib/gthread.c:1424
#4  0x00007f67f7253280 in gst_base_transform_activate (trans=0x7f67ec020400, active=0)
    at gstbasetransform.c:2780
#5  0x00007f67f7254d50 in gst_base_transform_sink_activate_push (pad=0x7f67ec0231d0, active=0)
    at gstbasetransform.c:2811
#6  0x00007f67f6f9d75b in gst_pad_activate_push (pad=0x7f67ec0231d0, active=0) at gstpad.c:956
#7  0x00007f67f6f9e4a8 in gst_pad_set_active (pad=0x7f67ec0231d0, active=0) at gstpad.c:718
#8  0x00007f67f6f7b520 in activate_pads (pad=0xa1d188, ret=0x7fff8f46a370, active=0x7f67ec022ac0)
    at gstelement.c:2845
#9  0x00007f67f6f8dd6e in gst_iterator_fold (it=0x8793d0, func=0x7f67f6f7b500 <activate_pads>, 
    ret=0x7fff8f46a370, user_data=0x7fff8f46a3dc) at gstiterator.c:549
#10 0x00007f67f6f7b486 in iterator_activate_fold_with_resync (iter=0x8793d0, 
    func=0x7f67f6f7b500 <activate_pads>, user_data=0x7fff8f46a3dc) at gstelement.c:2876
#11 0x00007f67f6f7db65 in gst_element_pads_activate (element=0x7f67ec020400, active=0) at gstelement.c:2921
#12 0x00007f67f6f8000a in gst_element_change_state_func (element=0x7f67ec020400, 
    transition=<value optimised out>) at gstelement.c:3002
#13 0x00007f67f6f7c7bc in gst_element_change_state (element=0xa1d188, transition=128) at gstelement.c:2761
#14 0x00007f67f6f7fd3b in gst_element_set_state_func (element=0x7f67ec020400, state=GST_STATE_READY)
    at gstelement.c:2717
#15 0x00007f67f6f6c77b in gst_bin_element_set_state (element=0x86e570, transition=<value optimised out>)
    at gstbin.c:2209
#16 gst_bin_change_state_func (element=0x86e570, transition=<value optimised out>) at gstbin.c:2518
#17 0x00007f67f42d137c in gst_decode_bin_change_state (element=<value optimised out>, transition=18)
    at gstdecodebin2.c:4027
#18 0x00007f67f6f7c7bc in gst_element_change_state (element=0xa1d188, transition=128) at gstelement.c:2761
#19 0x00007f67f6f7fd3b in gst_element_set_state_func (element=0x86e570, state=GST_STATE_READY)
    at gstelement.c:2717
#20 0x00007f67f6f6c77b in gst_bin_element_set_state (element=0x86e110, transition=<value optimised out>)
    at gstbin.c:2209
#21 gst_bin_change_state_func (element=0x86e110, transition=<value optimised out>) at gstbin.c:2518
#22 0x00007f67f42da067 in gst_uri_decode_bin_change_state (element=0x86e110, transition=18)
    at gsturidecodebin.c:2500
#23 0x00007f67f6f7c7bc in gst_element_change_state (element=0xa1d188, transition=128) at gstelement.c:2761
#24 0x00007f67f6f7fd3b in gst_element_set_state_func (element=0x86e110, state=GST_STATE_READY)
    at gstelement.c:2717
#25 0x00007f67f6f6c77b in gst_bin_element_set_state (element=0x983070, transition=<value optimised out>)
    at gstbin.c:2209
#26 gst_bin_change_state_func (element=0x983070, transition=<value optimised out>) at gstbin.c:2518
#27 0x00007f67f6fa0c07 in gst_pipeline_change_state (element=0x983070, transition=18) at gstpipeline.c:484
#28 0x00007f67f6f7c7bc in gst_element_change_state (element=0xa1d188, transition=128) at gstelement.c:2761
#29 0x00007f67f6f7fd3b in gst_element_set_state_func (element=0x983070, state=GST_STATE_READY)
    at gstelement.c:2717
#30 0x00007f67f76ab211 in discoverer_cleanup (dc=0x967500) at gstdiscoverer.c:1269
#31 0x00007f67f76ab4e6 in gst_discoverer_discover_uri (discoverer=0x967500, uri=<value optimised out>, 
    err=<value optimised out>) at gstdiscoverer.c:1566
#32 0x0000000000403467 in process_file (dc=0x967500, filename=<value optimised out>) at gst-discoverer.c:457
#33 0x0000000000403657 in main (argc=2, argv=0x7fff8f46af58) at gst-discoverer.c:547
(gdb) q
