reproducible Segmentation Fault using jogwheels on mc6000mk2 in non-vinyl mode

[blub]

I can reproducible let Mixxx crash when using the following setup:

 - Mixxx 2.0.0 on Debian/testing
 - Denon MC6000MK2 attached

doing the following:

 - turning off vinyl mode
 - searching for a CUE point using the jog wheels

After some spinning Mixxx crashes.

I was asked to let it crash a couple of times for more backtraces - so here they are (attached)

[Sean M. Pappalardo (pegasus-renegadetech)]

Looks like the crash is happening in soundtouch::TDStretch::overlapStereo() which makes me think the controller script may be sending a bad speed value to the Mixxx engine. Are you using a preset for that controller that came with Mixxx? Also, can you try changing the time-shifting library in Preferences to "Rubberband" and see if you can still reproduce the crash? What version of PortAudio is on your system?

[blub (wc-ubuntu)]

The preset is the one coming with Mixxx - no changes made.
In IRC you also requested the version of PortAudio, which is libportaudio2:amd64 19+svn20140130-1.
I will try the Rubberband change in a couple of hours and report back.

[Uwe Klotz (uklotzde-deactivatedaccount)]

Might be related to the following bug that has recently and hopefully been fixed in 2.1:
https://bugs.launchpad.net/mixxx/+bug/1577042

As an owner of an MC6000mk2 and author of the Mixxx mapping I will try to reproduce this issue.

[Uwe Klotz (uklotzde-deactivatedaccount)]

The backtraces for the crashes are the same in both bug reports. But the crash is not related to the controller, because in my case no controller was connected.

[Uwe Klotz (uklotzde-deactivatedaccount)]

I'm not able to reproduce the crash on the current 2.1.0-alpha-pre. Looks like this issue has been resolved by fixing the memory corruption issue in the SoundTouch engine buffer code recently (see above).

Are you able to compile and test 2.1.0-alpha-pre yourself? The current development version is very stable and performs really well. I use it myself all the time (with tag writing extensions) and recommend it over 2.0.0 ;) The beta release is only blocked by a non-existent Windows build server as I understood from the discussions.

If no new findings occur we should consider this bug as a duplicate and may close it with status "Fix Committed".

[blub (wc-ubuntu)]

I am and will compile Mixxx from master (I assume? I didn't find any branch / tag related to 2.1) myself, hence I'd recommend leaving this bug report open until I can confirm it being fixed / a duplicate.

[Uwe Klotz (uklotzde-deactivatedaccount)]

Great, master is the correct starting point! Currently no release branch for 2.1 has been created.

[raskolnikov (raskolnikov)]

I am suffering the same bug with the M-Audio Xponent wheel. I just tried with git master and the problem is still there. Using Rubberband does workaround, but my computer is slow so I often get the CPU meter on the red with it...

[Uwe Klotz (uklotzde-deactivatedaccount)]

Did you compile Mixxx from sources? Which OS?

It would be helpful if you attach a backtrace of such a crash. As already mentionend I am not able to reproduce this crash any more. Without further evidence we are not able to spot the corresponding cause somewhere in the code.

[raskolnikov (raskolnikov)]

Hi Uwe!

Sorry I was too brief. I am using Debian Sid, and built master from source with optimize=native. I am running on a 7-years old laptop with an Intel processor.

Anyways, I can't reproduce it now, so probably it was my fault... Actually I think I had some wrong linker paths and it was still running against some stuff from the distro when I first tried. I will do a longer practice session tomorrow and report back if I have any problems.

Thanks for the quick reply!

[raskolnikov (raskolnikov)]

I have been practicing the whole week with the new build on master and I can confirm that the bug seems gone.

Also, I played for like 4 hours straight at a club on Friday with this build (but Rubberband instead of SoundTouch) with no problems. Mixxx is really becoming way more stable with time. Thank you all team, you rock!

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/8555