WIKIABOUT

FOR TIPS, gUIDES & TUTORIALS

subscribe to our Youtube

GO TO YOUTUBE

14455 questions

17168 answers

28195 comments

0 members

Most popular tags

rut955 rut240 rut950 rutx11 rms vpn to openvpn wifi not sms trb140 firmware connection - ipsec on rutx12 rutx09 modbus
We are migrating to our new platform at https://community.teltonika.lt. Moving forward, you can continue discussions on this new platform. This current platform will be temporarily maintained for reference purposes.

Modem handling often results in SIGSEGV pagefault

0 votes
125 views 2 comments
by anonymous

Device: RUT950
FW: RUT9_R_00.07.00.2.

Quite often, after resetting modem (from UI) and followed by lots of AT-commands being sent to gsmd, this process seems to end with segfault. Bad/non-existent mobile network may contribute to this behaviour.

[...]
Tue Nov  9 09:23:32 2021 daemon.info unhandler[1854]: modem_init[1-1][16]: AT+CNMI=2,1,0,0,0
Tue Nov  9 09:23:32 2021 daemon.info unhandler[1854]: modem_init[16]: send to gsmd 'AT+CNMI=2,1,0,0,0'
Tue Nov  9 09:23:32 2021 daemon.info unhandler[1854]: modem_init[16]: get from gsmd OK
Tue Nov  9 09:23:32 2021 daemon.info unhandler[1854]:
Tue Nov  9 09:23:32 2021 daemon.info unhandler[1854]: modem_init[1-1][17]: AT+CPMS
Tue Nov  9 09:23:32 2021 daemon.info unhandler[1854]: cfg_value:|(null)|
Tue Nov  9 09:23:32 2021 daemon.info unhandler[1854]: modem_init[17]: send to gsmd 'AT+CPMS="SM","SM","SM"'
Tue Nov  9 09:23:32 2021 kern.info kernel: [ 5541.655248] do_page_fault(): sending SIGSEGV to unhandler for invalid read access from 05e205e4
Tue Nov  9 09:23:32 2021 kern.info kernel: [ 5541.664146] epc = 77f430dc in libc.so[77f18000+97000]
Tue Nov  9 09:23:32 2021 kern.info kernel: [ 5541.669321] ra  = 77f434b4 in libc.so[77f18000+97000]

1 Answer

0 votes
by anonymous
Hello,

I will try to reproduce these logs. First, have you noticed any impact on mobile connectivity because of that? Or SIM card connects even after these messages?

Regards.
by anonymous

I actually noticed the whole thing as I was pulling my hair on non-working mobile connection. After a while I found that it does matter which antenna you attach! Both antenna connectors on RUT950 are marked as "LTE" but the one next to SIM2 seem to be more like "MAIN" and the one next to SIM1 more like "AUX". With only one antenna, when on connector next to SIM1, no mobile connection, no network but on connector next to SIM2 the modem immediately registers and connects.  Did not know that.

So in a way, yes, I did notice severe impact on mobile connectivity but no, perhaps not because of that.. :-)

by anonymous
Hi,

RUT950 does have a single modem which means that both antennas should be attached only for a single SIM card. If you have only one antenna, then always attach it to the MAIN connector, because AUX is used only for data/signal correction.

Regards.