[Regression ncs v1.8.0] nRF9160-DK , Modem_shell demo , HARD FAULT after connecting over ppp

[adam_h]

Hello,

I was testing modem_shell demo in terms of using ppp. I'm using nrf9160dk board. 

I found issue present in ncs v1.7.1 https://devzone.nordicsemi.com/f/nordic-q-a/80776/nrf9160-dk-modem_shell-demo-ppp-unable-to-access-the-internet

When I'm using  v1.7.1 with applied changes from PR as advised, I'm able to connect with ppp client (from linux I'm executing: sudo pppd -detach /dev/ttyACM0 115200 noauth nocrtscts local ) without any issues

When I'm using ncs v1.8.0 which seems to have fix for this issue merged in (I verified that changes are present in cs/zephyr/subsys/net/ip/packet_socket.c), the problem with hard fault is still present.

[Håkon Alseth]

Hi,

 

Thank you for reporting this back to us. I can confirm that I see the same fault occuring from the "ppp_workq" thread.

I will report this internally.

 

Kind regards,

Håkon

[Håkon Alseth]

I got help from R&D to debug this issue, and the fault you're seeing is highly likely a side-effect to the ipv6 support having been added to the modem_shell.

If you add the flag "noccp" to the pppd options, it should work as intended:

$ sudo pppd -detach /dev/ttyACM0 115200 noauth nocrtscts local noccp
Using interface ppp0
Connect: ppp0 <--> /dev/ttyACM0
local  LL address fe80::xyz
remote LL address fe80::xyzz
local  IP address x.y.z.zz
remote IP address x.y.z.zz

 

Could you try this and report back?

 

Kind regards,

Håkon

[adam_h]

Hi ,
In case of hard fault that helped.
Right now I'm getting:

Using interface ppp0
Connect: ppp0 <--> /dev/ttyACM0
LCP: Rcvd Code-Reject for code 192, id 33
local IP address x.y.z.zz
remote IP address x.y.z.zz
LCP: Rcvd Code-Reject for code 192, id 33
LCP: Rcvd Code-Reject for code 192, id 33
LCP: Rcvd Code-Reject for code 192, id 33
LCP: Rcvd Code-Reject for code 192, id 33
LCP: Rcvd Code-Reject for code 192, id 33




[Håkon Alseth]

Hi,

 

Does the shell (uart1) output show anything specific?

You can also add "debug" to the pppd options to get a more verbose output on the PC side.

 

Are you able to for instance ping from the PC side?

ping -I ppp0 google.com

 

Kind regards,

Håkon

[adam_h]

There is nothing interesting on shell uart:

*** Booting Zephyr OS build v2.7.0-ncs1  ***

MOSH version:       v1.8.0
MOSH build id:      custom
MOSH build variant: dev

Initializing modemlib...


mosh:~$ Initialized modemlib


Network registration status: searching
Currently active system mode: LTE-M
LTE cell changed: ID: 61565196, Tracking area: 54003
RRC mode: Connected
PDN event: PDP context 0 activated
Network registration status: Connected - roaming
PSM parameter update: TAU: 10800, Active time: -1 seconds
Default PDN is active: starting PPP automatically.
modem data socket 4 created for modem data
PPP Zephyr data socket 5 created
Modem config for system mode: LTE-M
Modem config for LTE preference: No preference, automatically selected by the modem
Currently active system mode: LTE-M
Modem FW version:      mfw_nrf9160_1.2.3
Operator full name:   "Orange"
Operator short name:  "Orange"
Operator PLMN:        "26003"
Current cell id:       61565196 (0x03AB690C)
Current phy cell id:   421
Current band:          20
Current TAC:           54003 (0xD2F3)
Current rsrp:          26: -115dBm
Current snr:           27: 3dB
Mobile network time and date: 22/01/05,12:15:27+04
PDP context info 1:
  CID:                0
  PDN ID:             0
  PDP context active: yes
  PDP type:           IP
  APN:                xxx
  IPv4 MTU:           1500
  IPv4 address:       x.y.z.zz
  IPv6 address:       ::
  IPv4 DNS address:   x.y.z.zz, x.y.z.zz
  IPv6 DNS address:   ::, ::
PPP carrier ON
RRC mode: Idle
Dial up (IPv4) connection up
RRC mode: Connected
RRC mode: Idle
RRC mode: Connected
RRC mode: Idle
RRC mode: Connected

From PC pppd cal with debug I can see:

~ sudo pppd -detach /dev/ttyACM0 115200 noauth nocrtscts local noccp debug
using channel 6
Using interface ppp0
Connect: ppp0 <--> /dev/ttyACM0
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xf62fbb22> <pcomp> <accomp>]
rcvd [LCP ConfRej id=0x1 <asyncmap 0x0> <magic 0xf62fbb22> <pcomp> <accomp>]
sent [LCP ConfReq id=0x2]
rcvd [LCP ConfAck id=0x2]
rcvd [LCP ConfReq id=0x1 <mru 1500>]
sent [LCP ConfAck id=0x1 <mru 1500>]
sent [LCP EchoReq id=0x0 magic=0x0]
sent [IPCP ConfReq id=0x1 <compress VJ 0f 01> <addr 0.0.0.0>]
rcvd [IPCP ConfReq id=0x1 <addr x.y.z.zz> <ms-dns1 10.105.16.254> <ms-dns2 10.105.144.254>]
sent [IPCP ConfRej id=0x1 <ms-dns1 10.105.16.254> <ms-dns2 10.105.144.254>]
rcvd [IPV6CP ConfReq id=0x1 <addr fe80::0000:5eff:fe00:5371>]
Unsupported protocol 'IPv6 Control Protocol' (0x8057) received
sent [LCP ProtRej id=0x3 80 57 01 01 00 0e 01 0a 00 00 5e ff fe 00 53 71]
rcvd [LCP EchoRep id=0x0 magic=0x0]
rcvd [IPCP ConfRej id=0x1 <compress VJ 0f 01>]
sent [IPCP ConfReq id=0x2 <addr 0.0.0.0>]
rcvd [IPCP ConfReq id=0x2 <addr x.y.z.zz>]
sent [IPCP ConfAck id=0x2 <addr x.y.z.zz>]
rcvd [LCP CodeRej id=0x3 c0 21 08 03 00 14 80 57 01 01 00 0e 01 0a 00 00 5e ff]
LCP: Rcvd Code-Reject for code 192, id 33
rcvd [IPCP ConfNak id=0x2 <addr x.y.z.zz>]
sent [IPCP ConfReq id=0x3 <addr x.y.z.zz>]
rcvd [IPCP ConfAck id=0x3 <addr x.y.z.zz>]
local  IP address x.y.z.zz
remote IP address x.y.z.zz
Script /etc/ppp/ip-up started (pid 14054)
Script /etc/ppp/ip-up finished (pid 14054), status = 0x0
rcvd [IPV6CP ConfReq id=0x1 <addr fe80::0000:5eff:fe00:5371>]
Unsupported protocol 'IPv6 Control Protocol' (0x8057) received
sent [LCP ProtRej id=0x4 80 57 01 01 00 0e 01 0a 00 00 5e ff fe 00 53 71]
rcvd [LCP CodeRej id=0x4 c0 21 08 04 00 14 80 57 01 01 00 0e 01 0a 00 00 5e ff]
LCP: Rcvd Code-Reject for code 192, id 33

I tried to ping time.google.com (ip: 216.239.35.0) as I know it is on white list of my sim card but also without success.
Strange thing is that I'm also not able to ping it from modem shell. I need to make some more tries as I think I was able to do it in the past