dump1090 restart failed due to kernel module conflict

FlightAware ADS-B Flight Tracking
1

I keep my Raspberry Pi up to date with latest software (sudo apt-get update; sudo apt-get upgrade). I seem to have accidentally installed a kernel module that conflicts with dump1090, causing it to fail silently and thus not feed data to piaware.

Solution was to prevent the Linux kernel from loading the conflicting module. I did this by creating a file called /etc/modprobe.d/dvb_usb_rtl28xxu.conf containing this line:


install dvb_usb_rtl28xxu /bin/true

.

2

Interesting… Wonder if that has hit my dev box. What was the error you got and did it hang the whole PI or just dump1090?

Cheers!
LitterBug

3

Symptom was that dump1090 failed silently from the init script. Starting it manually showed an error message that explained the conflict with the kernel module (which had the device open). A look on the Debian forums recommended using a ‘fake start script’ to prevent the kernel from loading the conflicting module.

4

I might be wrong, but does blacklisting the relevant modules fix this?

/etc/modprobe.d/rtl-sdr-blacklist.conf


# This system has librtlsdr0 installed in order to
# use digital video broadcast receivers as generic
# software defined radios.
blacklist dvb_usb_rtl28xxu
blacklist e4000
blacklist rtl2832
5

You’re quite right! I just tried it on my system, and the blacklist file works. Seems like a cleaner solution, too.

BTW, my RP 2 is running this kernel:


jeremy@raspberrypi ~ $ uname -a
Linux raspberrypi 3.18.11-v7+ #781 SMP PREEMPT Tue Apr 21 18:07:59 BST 2015 armv7l GNU/Linux
6

Hmmm. Mine appears to be a hardware issue. Thing gets really hot then hangs with CPU kernel panic. Swapped PS and no better. Thanks for the heads up though, just in case we do run into this.

Cheers!
LitterBug

7

I’m running this same kernal on two RPi2 ADS-B feeders without any of the issues you describe. Both were built from scratch with the latest Debian/Wheezy starting point, dump1090-mutability, PiAware, etc…
…Tom

8

One difference is that I’m running plain dump1090 (not the ‘mutability’ version). Another could be that I somehow installed a kernel module that you don’t have.

You can list installed modules with ‘lsmod’. When I don’t blacklist I have ‘dvb_usb_rtl28xxu’ loaded. Do you?

9

Here’s my lsmod output…

pi@raspberrypi ~ $ lsmod
Module Size Used by
arc4 1745 0
ecb 2027 0
md4 3378 0
md5 1832 0
hmac 2825 0
nls_utf8 1165 0
cifs 285497 0
cfg80211 386508 0
rfkill 16651 1 cfg80211
dm_mod 86018 0
snd_bcm2835 18649 0
snd_pcm 73475 1 snd_bcm2835
snd_seq 53078 0
snd_seq_device 5628 1 snd_seq
snd_timer 17784 2 snd_pcm,snd_seq
snd 51038 5 snd_bcm2835,snd_timer,snd_pcm,snd_seq,snd_seq_device
sg 18271 0
uio_pdrv_genirq 2958 0
uio 8119 1 uio_pdrv_genirq

10

Hmm. You don’t have that kernel module, and thus don’t have the conflict.

I don’t know how I installed it! Linux is a wild and wily beast.

The thread will be here in case anyone else runs into a similar issue…

Happy ADSB-ing.
Jeremy