I was using my controller (kontrol S4 mk2) with sound playing and two tracks loaded and i faced a sudden segfault, but couldn't find find any interesting info. After allowing core file creation, mixxx segfaulted again (randomly, sound was playing) and i was able to extract a backtrace :
#0 0x00007f5f7e8935bd in _int_malloc (av=av@entry=0x7f5e5c000020, bytes=bytes@entry=24)
at malloc.c:3779
#1 0x00007f5f7e8962ed in __GI___libc_malloc (bytes=24) at malloc.c:3065
#2 0x00007f5f8333f011 in QMetaObject::activate(QObject*, int, int, void**) ()
at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3 0x000055ce2d7d19dc in ControlDoublePrivate::valueChanged(double, QObject*) (this=this@entry=0x55ce30a11dc0, _t1=<optimized out>, _t1@entry=1, _t2=<optimized out>) at lin64_build/control/moc_control.cc:140
#4 0x000055ce2d7be0d5 in ControlDoublePrivate::setInner(double, QObject*) (this=0x55ce30a11dc0, value=1, pSender=<optimized out>) at src/control/control.cpp:201
#5 0x000055ce2d7be18f in ControlDoublePrivate::set(double, QObject*) (this=0x55ce30a11dc0, value=<optimized out>, pSender=0x55ce30a11cd0) at src/control/control.cpp:188
#6 0x000055ce2da6e315 in ControlObject::set(double) (value=<optimized out>, this=<optimized out>)
at src/control/controlobject.h:96
#7 0x000055ce2da6e315 in EngineVuMeter::process(float*, int) (this=0x55ce30a66e20, pIn=<optimized out>, iBufferSize=2048) at src/engine/enginevumeter.cpp:86
#8 0x000055ce2da67c4b in EngineMaster::process(int) (this=0x55ce30a09680, iBufferSize=iBufferSize@entry=2048) at src/engine/enginemaster.cpp:706
#9 0x000055ce2ddb79fb in SoundManager::onDeviceOutputCallback(long) (this=<optimized out>, iFramesPerBuffer=iFramesPerBuffer@entry=1024) at src/soundio/soundmanager.cpp:599
#10 0x000055ce2ddb0ef4 in SoundDevicePortAudio::callbackProcessClkRef(long, float*, float const*, PaStreamCallbackTimeInfo const*, unsigned long) (this=0x55ce3125e920, framesPerBuffer=<optimized out>, out=<optimized out>, in=<optimized out>, timeInfo=<optimized out>, statusFlags=<optimized out>)
at src/soundio/sounddeviceportaudio.cpp:942
#11 0x00007f5f864508b4 in () at /usr/lib/x86_64-linux-gnu/libportaudio.so.2
#12 0x00007f5f864528c4 in () at /usr/lib/x86_64-linux-gnu/libportaudio.so.2
#13 0x00007f5f8645b7cc in () at /usr/lib/x86_64-linux-gnu/libportaudio.so.2
#14 0x00007f5f80e596db in start_thread (arg=0x7f5e55ffb700) at pthread_create.c:463
#15 0x00007f5f7e92088f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
Operating system :
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 18.04.1 LTS
Release: 18.04
Codename: bionic
CPU architecture : Intel(R) Core(TM) i5-7200U CPU @ 2.50GHz
$ uname -a
Linux oleg 4.15.0-43-generic #46-Ubuntu SMP Thu Dec 6 14:45:28 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
Your video
$ sudo lspci | grep VGA
00:02.0 VGA compatible controller: Intel Corporation HD Graphics 620 (rev 02)
sound hardware
traktor kontrol S4 mk2 one
mixxx version : 2.2
$ git log --max-count=1
commit d9d7ea6404de71c86beacfc86f9087dc8db0fc58 (HEAD -> 2.2, tag: release-2.2.0, origin/2.2)
Merge: 0e685c1a9 7f1d14931
Author: Daniel Schürmann <email address hidden>
Date: Mon Dec 24 07:37:23 2018 +0100
If malloc.c segfaults, it tries to allocate memory on a bad address. This can happen if either the Ram is faulty or a previous call previus call has corrupted the heap control structure.
I assume the error is unrelated to the current call in the stack trace.
Can you find a pattern that always crashes?
Did you do something special before the crash?