PulseAudio 1.1, this happens regularly when playing back DVB-T through
GStreamer pulsesink and Flash over ALSA to PA bridge.


Thread 6 (Thread 0x7f763aeaf780 (LWP 1575)):
#0  0x00007f7637819693 in ppoll () from /lib64/libc.so.6
#1  0x00007f763a2775d7 in pa_mainloop_poll (m=0x24f8e50) at pulse/mainloop.c:883
#2  0x00007f763a277ba9 in pa_mainloop_iterate (m=0x24f8e50, block=<optimized out>, retval=0x7fff18abe574) at pulse/mainloop.c:957
#3  0x00007f763a277c60 in pa_mainloop_run (m=0x24f8e50, retval=0x7fff18abe574) at pulse/mainloop.c:975
#4  0x0000000000406a08 in main (argc=<optimized out>, argv=<optimized out>) at daemon/main.c:1132

Thread 5 (Thread 0x7f762a37f700 (LWP 1595)):
#0  0x00007f7638186b70 in sem_wait () from /lib64/libpthread.so.0
#1  0x00007f7639e26568 in pa_semaphore_wait (s=0x255bbe0) at pulsecore/semaphore-posix.c:63
#2  0x00007f763aa316da in pa_asyncmsgq_send (a=0x2534d90, object=<optimized out>, code=<optimized out>, userdata=<optimized out>, offset=<optimized out>, chunk=<optimized out>) at pulsecore/asyncmsgq.c:167
#3  0x00007f7628979046 in request_memblock (length=21112, o=0x2520950) at modules/module-combine-sink.c:410
#4  sink_input_pop_cb (i=<optimized out>, nbytes=21112, chunk=0x7f762a37c4d0) at modules/module-combine-sink.c:421
#5  0x00007f763aa58edb in pa_sink_input_peek (i=0x2545cb0, slength=21112, chunk=0x7f762a37c610, volume=0x7f762a37c628) at pulsecore/sink-input.c:812
#6  0x00007f763aa5f46a in fill_mix_info (s=0x2520a20, length=0x7f762a37ecb8, info=0x7f762a37c610, maxinfo=32) at pulsecore/sink.c:950
#7  0x00007f763aa61e27 in pa_sink_render_into (s=0x2520a20, target=0x7f762a37ed10) at pulsecore/sink.c:1189
#8  0x00007f763aa62379 in pa_sink_render_into_full (s=0x2520a20, target=0x7f762a37eda0) at pulsecore/sink.c:1273
#9  0x00007f762b0a4b80 in mmap_write (on_timeout=false, polled=false, sleep_usec=<synthetic pointer>, u=0x2517fc0) at modules/alsa/alsa-sink.c:632
#10 thread_func (userdata=0x2517fc0) at modules/alsa/alsa-sink.c:1656
#11 0x00007f7639e26308 in internal_thread_func (userdata=0x2506ce0) at pulsecore/thread-posix.c:83
#12 0x00007f7638180d90 in start_thread () from /lib64/libpthread.so.0
#13 0x00007f7637821f5d in clone () from /lib64/libc.so.6

Thread 4 (Thread 0x7f762ab80700 (LWP 1591)):
#0  0x00007f7638186b70 in sem_wait () from /lib64/libpthread.so.0
#1  0x00007f7639e26568 in pa_semaphore_wait (s=0x7f761c000a90) at pulsecore/semaphore-posix.c:63
#2  0x00007f763aa316da in pa_asyncmsgq_send (a=0x25370e0, object=<optimized out>, code=<optimized out>, userdata=<optimized out>, offset=<optimized out>, chunk=<optimized out>) at pulsecore/asyncmsgq.c:167
#3  0x00007f7628979046 in request_memblock (length=21272, o=0x2534ad0) at modules/module-combine-sink.c:410
#4  sink_input_pop_cb (i=<optimized out>, nbytes=21272, chunk=0x7f762ab7d4d0) at modules/module-combine-sink.c:421
#5  0x00007f763aa58edb in pa_sink_input_peek (i=0x253eb30, slength=21272, chunk=0x7f762ab7d610, volume=0x7f762ab7d628) at pulsecore/sink-input.c:812
#6  0x00007f763aa5f46a in fill_mix_info (s=0x2519450, length=0x7f762ab7fcb8, info=0x7f762ab7d610, maxinfo=32) at pulsecore/sink.c:950
#7  0x00007f763aa61e27 in pa_sink_render_into (s=0x2519450, target=0x7f762ab7fd10) at pulsecore/sink.c:1189
#8  0x00007f763aa62379 in pa_sink_render_into_full (s=0x2519450, target=0x7f762ab7fda0) at pulsecore/sink.c:1273
#9  0x00007f762b0a4b80 in mmap_write (on_timeout=false, polled=false, sleep_usec=<synthetic pointer>, u=0x25045d0) at modules/alsa/alsa-sink.c:632
#10 thread_func (userdata=0x25045d0) at modules/alsa/alsa-sink.c:1656
#11 0x00007f7639e26308 in internal_thread_func (userdata=0x2518790) at pulsecore/thread-posix.c:83
#12 0x00007f7638180d90 in start_thread () from /lib64/libpthread.so.0

#13 0x00007f7637821f5d in clone () from /lib64/libc.so.6

Thread 3 (Thread 0x7f7628972700 (LWP 1600)):
#0  pa_memblockq_push (bq=0x2536580, uchunk=<optimized out>) at pulsecore/memblockq.c:328
#1  0x00007f7639e111f2 in pa_memblockq_push_align (bq=0x2536580, chunk=<optimized out>) at pulsecore/memblockq.c:786
#2  0x00007f7628976650 in sink_input_process_msg (obj=0x2545cb0, code=7, data=0x0, offset=0, chunk=0x7f7628971bc0) at modules/module-combine-sink.c:574
#3  0x00007f763aa31f51 in pa_asyncmsgq_process_one (a=0x25375a0) at pulsecore/asyncmsgq.c:276
#4  0x00007f7628976f89 in render_memblock (length=21112, o=0x2520950, u=0x252a250) at modules/module-combine-sink.c:365
#5  sink_process_msg (o=0x2534f00, code=28, data=0x2520950, offset=21112, chunk=0x0) at modules/module-combine-sink.c:779
#6  0x00007f763aa4ddb2 in asyncmsgq_read_work (i=0x7f7618000980) at pulsecore/rtpoll.c:566
#7  0x00007f763aa4d2bf in pa_rtpoll_run (p=0x25074d0, wait_op=true) at pulsecore/rtpoll.c:238
#8  0x00007f76289777ae in thread_func (userdata=0x252a250) at modules/module-combine-sink.c:331
#9  0x00007f7639e26308 in internal_thread_func (userdata=0x253c9c0) at pulsecore/thread-posix.c:83
#10 0x00007f7638180d90 in start_thread () from /lib64/libpthread.so.0
#11 0x00007f7637821f5d in clone () from /lib64/libc.so.6

Thread 2 (Thread 0x7f762937d700 (LWP 1599)):
#0  0x00007f7638186b70 in sem_wait () from /lib64/libpthread.so.0
#1  0x00007f7639e26568 in pa_semaphore_wait (s=0x2507200) at pulsecore/semaphore-posix.c:63
#2  0x00007f763aa316da in pa_asyncmsgq_send (a=0x25369f0, object=<optimized out>, code=<optimized out>, userdata=<optimized out>, offset=<optimized out>, chunk=<optimized out>) at pulsecore/asyncmsgq.c:167
#3  0x00007f7628979046 in request_memblock (length=21144, o=0x253b540) at modules/module-combine-sink.c:410
#4  sink_input_pop_cb (i=<optimized out>, nbytes=21144, chunk=0x7f762937a4d0) at modules/module-combine-sink.c:421
#5  0x00007f763aa58edb in pa_sink_input_peek (i=0x254ea30, slength=21144, chunk=0x7f762937a610, volume=0x7f762937a628) at pulsecore/sink-input.c:812
#6  0x00007f763aa5f46a in fill_mix_info (s=0x252e1b0, length=0x7f762937ccb8, info=0x7f762937a610, maxinfo=32) at pulsecore/sink.c:950
#7  0x00007f763aa61e27 in pa_sink_render_into (s=0x252e1b0, target=0x7f762937cd10) at pulsecore/sink.c:1189
#8  0x00007f763aa62379 in pa_sink_render_into_full (s=0x252e1b0, target=0x7f762937cda0) at pulsecore/sink.c:1273
#9  0x00007f762b0a4b80 in mmap_write (on_timeout=false, polled=false, sleep_usec=<synthetic pointer>, u=0x2526de0) at modules/alsa/alsa-sink.c:632
#10 thread_func (userdata=0x2526de0) at modules/alsa/alsa-sink.c:1656
#11 0x00007f7639e26308 in internal_thread_func (userdata=0x2507080) at pulsecore/thread-posix.c:83
#12 0x00007f7638180d90 in start_thread () from /lib64/libpthread.so.0
#13 0x00007f7637821f5d in clone () from /lib64/libc.so.6

Thread 1 (Thread 0x7f7629b7e700 (LWP 1597)):
#0  0x00007f7637767285 in raise () from /lib64/libc.so.6
#1  0x00007f7637768b9b in abort () from /lib64/libc.so.6
#2  0x00007f7639e0fabb in drop_block (bq=0x254c250, q=0x7f761800fbd0) at pulsecore/memblockq.c:180
#3  0x00007f7639e10014 in pa_memblockq_push (bq=0x254c250, uchunk=<optimized out>) at pulsecore/memblockq.c:328
#4  0x00007f7639e111f2 in pa_memblockq_push_align (bq=0x254c250, chunk=<optimized out>) at pulsecore/memblockq.c:786
#5  0x00007f763aa58f7d in pa_sink_input_peek (i=0x254a390, slength=21556, chunk=0x7f7629b7b610, volume=0x7f7629b7b628) at pulsecore/sink-input.c:886
#6  0x00007f763aa5f46a in fill_mix_info (s=0x2527d90, length=0x7f7629b7dcb8, info=0x7f7629b7b610, maxinfo=32) at pulsecore/sink.c:950
#7  0x00007f763aa61e27 in pa_sink_render_into (s=0x2527d90, target=0x7f7629b7dd10) at pulsecore/sink.c:1189
#8  0x00007f763aa62379 in pa_sink_render_into_full (s=0x2527d90, target=0x7f7629b7dda0) at pulsecore/sink.c:1273
#9  0x00007f762b0a4b80 in mmap_write (on_timeout=false, polled=false, sleep_usec=<synthetic pointer>, u=0x2520320) at modules/alsa/alsa-sink.c:632
#10 thread_func (userdata=0x2520320) at modules/alsa/alsa-sink.c:1656
#11 0x00007f7639e26308 in internal_thread_func (userdata=0x25269b0) at pulsecore/thread-posix.c:83
#12 0x00007f7638180d90 in start_thread () from /lib64/libpthread.so.0
#13 0x00007f7637821f5d in clone () from /lib64/libc.so.6



Thread 1 (Thread 0x7f7629b7e700 (LWP 1597)):
#0  0x00007f7637767285 in raise () from /lib64/libc.so.6
No symbol table info available.
#1  0x00007f7637768b9b in abort () from /lib64/libc.so.6
No symbol table info available.
#2  0x00007f7639e0fabb in drop_block (bq=0x254c250, q=0x7f761800fbd0) at pulsecore/memblockq.c:180
        __func__ = "drop_block"
        __PRETTY_FUNCTION__ = "drop_block"
#3  0x00007f7639e10014 in pa_memblockq_push (bq=0x254c250, uchunk=<optimized out>) at pulsecore/memblockq.c:328
        p = 0x7f761800fbd0
        q = 0x7f7618011cf0
        n = <optimized out>
        chunk = {memblock = 0x7f76200068d0, index = 0, length = 444}
        old = 35585868
        __func__ = "pa_memblockq_push"
        __PRETTY_FUNCTION__ = "pa_memblockq_push"
#4  0x00007f7639e111f2 in pa_memblockq_push_align (bq=0x254c250, chunk=<optimized out>) at pulsecore/memblockq.c:786
        r = <optimized out>
        rchunk = {memblock = 0x7f76200068d0, index = 0, length = 444}
        __func__ = "pa_memblockq_push_align"
        __PRETTY_FUNCTION__ = "pa_memblockq_push_align"
#5  0x00007f763aa58f7d in pa_sink_input_peek (i=0x254a390, slength=21556, chunk=0x7f7629b7b610, volume=0x7f7629b7b628) at pulsecore/sink-input.c:886
        rchunk = {memblock = 0x7f76200068d0, index = 0, length = 444}
        wchunk = {memblock = 0x7f7618092740, index = 0, length = 444}
        nvfs = <optimized out>
        tchunk = {memblock = 0x7f7618092740, index = 0, length = 444}
        do_volume_adj_here = false
        need_volume_factor_sink = false
        volume_is_norm = true
        block_size_max_sink = 65472
        block_size_max_sink_input = 64960
        ilength = 21556
        __func__ = "pa_sink_input_peek"
        __PRETTY_FUNCTION__ = "pa_sink_input_peek"
#6  0x00007f763aa5f46a in fill_mix_info (s=0x2527d90, length=0x7f7629b7dcb8, info=0x7f7629b7b610, maxinfo=32) at pulsecore/sink.c:950
        i = 0x254a390
        n = 0

        state = 0xffffffffffffffff
        mixlength = 21556
#7  0x00007f763aa61e27 in pa_sink_render_into (s=0x2527d90, target=0x7f7629b7dd10) at pulsecore/sink.c:1189
        info = {{chunk = {memblock = 0x0, index = 0, length = 0}, volume = {channels = 2 '\002', values = {65536, 65536, 0 <repeats 30 times>}}, userdata = 0x0, ptr = 0x0, linear = {{i = 0, f = 0} <repeats 32 times>}}, {chunk = {
              memblock = 0x0, index = 0, length = 0}, volume = {channels = 0 '\000', values = {0 <repeats 32 times>}}, userdata = 0x0, ptr = 0x0, linear = {{i = 0, f = 0} <repeats 32 times>}} <repeats 28 times>, {chunk = {
              memblock = 0x0, index = 0, length = 0}, volume = {channels = 0 '\000', values = {0 <repeats 17 times>, 39038112, 0, 983769745, 32630, 0, 0, 719254844, 32630, 699914544, 32630, 722015846, 32630, 0, 0, 39038112}}, 
            userdata = 0x7f7624001bb0, ptr = 0x1e, linear = {{i = 1, f = 1.40129846e-45}, {i = 0, f = 0}, {i = 941128496, f = 3.63543513e-05}, {i = 32630, f = 4.57243689e-41}, {i = 16384, f = 2.2958874e-41}, {i = 1142960697, 
                f = 640.784729}, {i = 8, f = 1.12103877e-44}, {i = 0, f = 0}, {i = 699914688, f = 8.16460614e-14}, {i = 32630, f = 4.57243689e-41}, {i = 941127129, f = 3.63493782e-05}, {i = 32630, f = 4.57243689e-41}, {i = 0, 
                f = 0}, {i = 0, f = 0}, {i = 970975181, f = 0.000427065796}, {i = 32630, f = 4.57243689e-41}, {i = 39020320, f = 1.55314272e-37}, {i = 0, f = 0}, {i = 603986864, f = 2.77790278e-17}, {i = 32630, 
                f = 4.57243689e-41}, {i = 39038192, f = 1.55514624e-37}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 983836229, f = 0.00125236122}, {i = 32630, f = 4.57243689e-41}, {
                i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}, {i = 0, f = 0}}}, {chunk = {memblock = 0x0, index = 6202034166383071488, length = 1}, volume = {channels = 144 '\220', values = {2013265920, 39038112, 0, 983769745, 
                32630, 0, 0, 983770570, 32630, 0, 0, 975739610, 32630, 603986672, 32630, 930812846, 32630, 603986864, 32630, 48, 0, 0, 0, 352256, 0, 356352, 0, 0, 0, 1, 0, 0}}, userdata = 0x60, ptr = 0x0, linear = {{i = 0, 
                f = 0}, {i = 0, f = 0}, {i = 4, f = 5.60519386e-45}, {i = 49, f = 6.86636248e-44}, {i = 91, f = 1.2751816e-43}, {i = 110, f = 1.54142831e-43}, {i = 119, f = 1.66754517e-43}, {i = 124, f = 1.7376101e-43}, {
                i = 984076604, f = 0.00128034456}, {i = 32630, f = 4.57243689e-41}, {i = 536870944, f = 1.08420631e-19}, {i = 32630, f = 4.57243689e-41}, {i = 48, f = 6.72623263e-44}, {i = 0, f = 0}, {i = 6728128, 
                f = 9.42811543e-39}, {i = 0, f = 0}, {i = 4, f = 5.60519386e-45}, {i = 0, f = 0}, {i = 402743072, f = 1.67208851e-24}, {i = 32630, f = 4.57243689e-41}, {i = 699914976, f = 8.1648013e-14}, {i = 32630, 
                f = 4.57243689e-41}, {i = 415234212, f = 4.96234057e-24}, {i = 32767, f = 4.59163468e-41}, {i = 973358408, f = 0.00050457241}, {i = 32630, f = 4.57243689e-41}, {i = 971045808, f = 0.000429121312}, {i = 32630, 
                f = 4.57243689e-41}, {i = 35534756, f = 1.16239748e-37}, {i = 0, f = 0}, {i = 970999641, f = 0.000427777675}, {i = 32630, f = 4.57243689e-41}}}, {chunk = {memblock = 0x7f7629b7db30, index = 140145721823729, 
              length = 38960528}, volume = {channels = 80 'P', values = {32630, 699915256, 32630, 39020720, 0, 536879792, 32630, 971046821, 32630, 39020896, 0, 124, 0, 0, 0, 971029903, 32630, 402730208, 32630, 719254094, 32630, 
                73298, 0, 39020720, 0, 699915376, 32630, 0, 0, 39020720, 0, 39020720}}, userdata = 0x0, ptr = 0x7f7639e111e1, linear = {{i = 38960640, f = 1.54645236e-37}, {i = 0, f = 0}, {i = 699915376, f = 8.16507235e-14}, {
                i = 32630, f = 4.57243689e-41}, {i = 39036000, f = 1.55490051e-37}, {i = 0, f = 0}, {i = 983771186, f = 0.00124478922}, {i = 32630, f = 4.57243689e-41}, {i = 986355656, f = 0.00154566113}, {i = 32630, 
                f = 4.57243689e-41}, {i = 983765216, f = 0.00124409422}, {i = 32630, f = 4.57243689e-41}, {i = 39101328, f = 1.56222403e-37}, {i = 0, f = 0}, {i = 970999357, f = 0.00042776941}, {i = 32630, f = 4.57243689e-41}, {
                i = 39013680, f = 1.55239835e-37}, {i = 0, f = 0}, {i = 699915408, f = 8.16509403e-14}, {i = 32630, f = 4.57243689e-41}, {i = 699915436, f = 8.16511301e-14}, {i = 32630, f = 4.57243689e-41}, {i = 983767230, 
                f = 0.00124432868}, {i = 32630, f = 4.57243689e-41}, {i = 39013680, f = 1.55239835e-37}, {i = 0, f = 0}, {i = -333885184, f = -7.41392648e+26}, {i = 1444023606, f = 4.01463595e+13}, {i = 403094688, 
                f = 1.74143254e-24}, {i = 32630, f = 4.57243689e-41}, {i = 39014048, f = 1.5524396e-37}, {i = 0, f = 0}}}}
        n = <optimized out>
        length = 21556
        block_size_max = <optimized out>
        __func__ = "pa_sink_render_into"
        __PRETTY_FUNCTION__ = "pa_sink_render_into"
#8  0x00007f763aa62379 in pa_sink_render_into_full (s=0x2527d90, target=0x7f7629b7dda0) at pulsecore/sink.c:1273
        chunk = {memblock = 0x255acf0, index = 13004, length = 21556}
        l = 21556
        d = <optimized out>
        __func__ = "pa_sink_render_into_full"
        __PRETTY_FUNCTION__ = "pa_sink_render_into_full"
#9  0x00007f762b0a4b80 in mmap_write (on_timeout=false, polled=false, sleep_usec=<synthetic pointer>, u=0x2520320) at modules/alsa/alsa-sink.c:632
        chunk = {memblock = 0x255acf0, index = 0, length = 34560}
        err = <optimized out>

        frames = 8640
        sframes = <optimized out>
        p = <optimized out>
        areas = 0x251fef0
        offset = 61424
        n = <optimized out>
        n_bytes = 34560
        r = <optimized out>
        after_avail = false
        process_usec = 20000
        left_to_play = <optimized out>
        work_done = false
        max_sleep_usec = 180000
        j = 1
#10 thread_func (userdata=0x2520320) at modules/alsa/alsa-sink.c:1656
        work_done = <optimized out>
        sleep_usec = 0
        on_timeout = <optimized out>
        ret = <optimized out>
        rtpoll_sleep = 0
        u = 0x2520320
        revents = 0
        __func__ = "thread_func"
        __PRETTY_FUNCTION__ = "thread_func"
#11 0x00007f7639e26308 in internal_thread_func (userdata=0x25269b0) at pulsecore/thread-posix.c:83
        t = 0x25269b0
#12 0x00007f7638180d90 in start_thread () from /lib64/libpthread.so.0
No symbol table info available.
#13 0x00007f7637821f5d in clone () from /lib64/libc.so.6
No symbol table info available.