Jack on Beaglebone: jackd crashes with bus error!?


I’m running ubuntu on the Beaglebone A5. I’m using jack to capture sound from a custom-made soundcard connected to the beaglebone. Until very recently jack was running just fine, however, suddenly I can’t start the jack server anymore as it crashes with a ‘Bus error’.

Only a few hours ago I was able to start a jack server with:

jackd -d alsa -p 256 -n 4 -C hw:0 -r 48000 -i 8

Then I just installed g++ and libjack-dev packages in order to compile a simple jack client. Since then starting a jack server gives me:

ubuntu@arm:~$ jackd -v -d alsa -p 256 -n 4 -C hw:0 -r 48000 -i 8

jackd 0.121.0
Copyright 2001-2009 Paul Davis, Stephane Letz, Jack O’Quinn, Torben Hohn and others.
This is free software, and you are welcome to redistribute it
under certain conditions; see the file COPYING for details

getting driver descriptor from /usr/lib/arm-linux-gnueabi/jack/jack_oss.so
getting driver descriptor from /usr/lib/arm-linux-gnueabi/jack/jack_net.so
getting driver descriptor from /usr/lib/arm-linux-gnueabi/jack/jack_alsa.so
getting driver descriptor from /usr/lib/arm-linux-gnueabi/jack/jack_dummy.so
JACK compiled with System V SHM support.
server `default’ registered
loading driver …
registered builtin port type 32 bit float mono audio
registered builtin port type 8 bit raw midi
clock source = system clock via clock_gettime
start poll on 3 fd’s
new client: alsa_pcm, id = 1 type 1 @ 0x17340 fd = -1
apparent rate = 48000
creating alsa driver … -|hw:0|256|4|48000|8|0|nomon|swmeter|-|32bit
control device hw:0
configuring for 48000Hz, period = 256 frames (5.3 ms), buffer = 4 periods
ALSA: final selected sample format for capture: 32bit integer little-endian
ALSA: use 16 periods for capture
new buffer size 256
resizing port buffer segment for type 0, one buffer = 1024 bytes
resizing port buffer segment for type 1, one buffer = 1024 bytes
registered port system:capture_1, offset = 1024
registered port system:capture_2, offset = 2048
registered port system:capture_3, offset = 3072
registered port system:capture_4, offset = 4096
registered port system:capture_5, offset = 5120
registered port system:capture_6, offset = 6144
registered port system:capture_7, offset = 7168
registered port system:capture_8, offset = 8192
++ jack_sort_graph
++ jack_rechain_graph():
– jack_rechain_graph()
– jack_sort_graph
830 waiting for signals
Bus error

It doesn’t seem to be a problem with ALSA as I’m able to record via ALSA. When trying to start jackd the kernel gives me two kind of nebulous messages:

[ 1870.399810] Alignment trap: not handling instruction edc76a06 at [<401375ca>]
[ 1870.407562] Unhandled fault: alignment exception (0x801) at 0x400ea1e6

I really would appreciate any kind of suggestion or hint on this!


Turned out that I had been running jack2 and installing libjack-dev changed my jack installation back to jack1. Installing package libjack-jackd2-dev instead reverted to jack2 and solved the issue.



I’m only a beginner and I see that you have your Jack up and running now. Unfortunately for me I have not been able to get Jack server running, so far I have a beaglebone A5 as well, with Ubuntu raring and I have installed ALSA and Jackd packages with apt-get.

Starting the server will give me two errors:

  1. Failed to connect to session bus for device reservation Unable to autolaunch a dbus-daemon without a $DISPLAY for X11
    If I do an SSH with -CX I manage to get rid of this issue but I still have the following one:

  2. "Cannot lock down 82278944 byte memory area (Cannot allocate memory)
    Bus error"

I know this is to much to ask but could you describe the steps you followed for getting your system to work with Jack?

Thanks a lot