SIG32 when debugging with pipewire

[Daniel Schürmann]

Mixxx crashes when trying to reconfigure from Jack to ALSA API
This was tested with Mixxx 2.4 alpha on Ubuntu 20.4

mixxx: src/hostapi/jack/pa_jack.c:820: Terminate: Zusicherung »err == 0« nicht erfüllt.
Abgebrochen (Speicherabzug geschrieben)

[Daniel Schürmann (daschuer)]

Subsequent starts are crashing with:

debug [Main] JACK client name set
ALSA lib pcm_dsnoop.c:641:(snd_pcm_dsnoop_open) unable to open slave
ALSA lib pcm_dmix.c:1089:(snd_pcm_dmix_open) unable to open slave
ALSA lib pcm.c:2642:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear
ALSA lib pcm.c:2642:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe
ALSA lib pcm.c:2642:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side
[New Thread 0x7fffd4f52700 (LWP 4185)]
[New Thread 0x7fffd4ed1700 (LWP 4186)]
Cannot lock down 82280346 byte memory area (Nicht genügend Hauptspeicher verfügbar)

Thread 12 "mixxx" received signal SIG32, Real-time event 32.
[Switching to Thread 0x7fffd4ed1700 (LWP 4186)]
__libc_read (nbytes=4, buf=0x7fffd4ed0340, fd=24)
    at ../sysdeps/unix/sysv/linux/read.c:26
26 ../sysdeps/unix/sysv/linux/read.c: Datei oder Verzeichnis nicht gefunden.
(gdb) bt
#0 __libc_read (nbytes=4, buf=0x7fffd4ed0340, fd=24)
    at ../sysdeps/unix/sysv/linux/read.c:26
#1 __libc_read (fd=24, buf=0x7fffd4ed0340, nbytes=4)
    at ../sysdeps/unix/sysv/linux/read.c:24
#2 0x00007ffff31d54c2 in () at /lib/x86_64-linux-gnu/libjack.so.0
#3 0x00007ffff31d891d in () at /lib/x86_64-linux-gnu/libjack.so.0
#4 0x00007ffff31d4280 in () at /lib/x86_64-linux-gnu/libjack.so.0
#5 0x00007ffff34eb609 in start_thread (arg=<optimized out>)
    at pthread_create.c:477
#6 0x00007ffff3412293 in clone ()
    at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
(gdb)

[Daniel Schürmann (daschuer)]

Now Jack my system is permanently broken ..

Mixxx alwasy crashes when starting and JACK is running:

Thread 11 (Thread 0x7fffd56ce700 (LWP 2366)):
#0 __libc_read (nbytes=4, buf=0x7fffd56cd340, fd=23) at ../sysdeps/unix/sysv/linux/read.c:26
#1 __libc_read (fd=23, buf=0x7fffd56cd340, nbytes=4) at ../sysdeps/unix/sysv/linux/read.c:24
#2 0x00007ffff31d54c2 in () at /lib/x86_64-linux-gnu/libjack.so.0
#3 0x00007ffff31d891d in () at /lib/x86_64-linux-gnu/libjack.so.0
#4 0x00007ffff31d4280 in () at /lib/x86_64-linux-gnu/libjack.so.0
#5 0x00007ffff34eb609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6 0x00007ffff3412293 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 10 (Thread 0x7fffd574f700 (LWP 2365)):
#0 futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x5555574b4218) at ../sysdeps/nptl/futex-internal.h:183
#1 __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5555574b41c0, cond=0x5555574b41f0) at pthread_cond_wait.c:508
#2 __pthread_cond_wait (cond=0x5555574b41f0, mutex=0x5555574b41c0) at pthread_cond_wait.c:638
#3 0x00007ffff31d4d32 in () at /lib/x86_64-linux-gnu/libjack.so.0
#4 0x00007ffff31cc83d in () at /lib/x86_64-linux-gnu/libjack.so.0
--Type <RET> for more, q to quit, c to continue without paging--
#5 0x00007ffff31d4280 in () at /lib/x86_64-linux-gnu/libjack.so.0
#6 0x00007ffff34eb609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7 0x00007ffff3412293 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 9 (Thread 0x7fffd6d4a700 (LWP 2364)):
#0 futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x5555569e23f0) at ../sysdeps/nptl/futex-internal.h:183
#1 __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5555569e23a0, cond=0x5555569e23c8) at pthread_cond_wait.c:508
#2 __pthread_cond_wait (cond=0x5555569e23c8, mutex=0x5555569e23a0) at pthread_cond_wait.c:638
#3 0x00007ffff3968b0f in QWaitCondition::wait(QMutex*, QDeadlineTimer) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4 0x00007ffff3968c01 in QWaitCondition::wait(QMutex*, unsigned long) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5 0x0000555555afe950 in EngineSideChain::run() (this=0x5555569b1340) at /home/sperry/workspace/mixxx/src/engine/sidechain/enginesidechain.cpp:109
#6 0x00007ffff39629d2 in () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7 0x00007ffff34eb609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#8 0x00007ffff3412293 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:--Type <RET> for more, q to quit, c to continue without paging--
95

Thread 8 (Thread 0x7fffe089f700 (LWP 2363)):
#0 futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55555664f9c0) at ../sysdeps/nptl/futex-internal.h:183
#1 __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55555664f970, cond=0x55555664f998) at pthread_cond_wait.c:508
#2 __pthread_cond_wait (cond=0x55555664f998, mutex=0x55555664f970) at pthread_cond_wait.c:638
#3 0x00007ffff3968b0f in QWaitCondition::wait(QMutex*, QDeadlineTimer) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4 0x00007ffff3968c01 in QWaitCondition::wait(QMutex*, unsi...

[Daniel Schürmann (daschuer)]

Cool, it crashes only under GDB.

Maybe something depends on uninitialized memory

[Daniel Schürmann (daschuer)]

That's normal i can just continue twice ...

https://gnobal.net/591/what-is-sig32-during-a-gdb-debug-session

[Jan Holthuis (holthuis-jan)]

I also see SIG32 with pipewire, and usually use "handle SIG32 nostop" to get rid of them.

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/10353