[yocto] connmand+dbus. Which alternatives?

Discussion:

Mauro Ziliani

2018-12-06 06:50:21 UTC

Hi all.

I'm working on a imx6dl sabresd project with an usb wifi dongle (edimax
EW7811un)

My app uses Connman by DBus to manage ethernet and wifi connections.

Normally the sytstem works well. Sometimes, randomly, the system freeze
or the app crashes.

I made many test and this happens when the system is connected to a SSID.

So I suspect that the problem is in connamd_1.31+dbus_1.10.6

I'm using Yocto fsl 4.1.5-2.0.1 qith Qt5 5.6.2

Can you suggest me an alternative to connmand?

Best regards,

MZ

--

ChenQi

2018-12-06 07:13:42 UTC

Permalink

wifi connection could be managed by wpa-supplicant.

Best Regards,
Chen Qi

Post by Mauro Ziliani
Hi all.
I'm working on a imx6dl sabresd project with an usb wifi dongle (edimax
EW7811un)
My app uses Connman by DBus to manage ethernet and wifi connections.
Normally the sytstem works well. Sometimes, randomly, the system freeze
or the app crashes.
I made many test and this happens when the system is connected to a SSID.
So I suspect that the problem is in connamd_1.31+dbus_1.10.6
I'm using Yocto fsl 4.1.5-2.0.1 qith Qt5 5.6.2
Can you suggest me an alternative to connmand?
Best regards,
MZ

Ulrich Ölmann

2018-12-06 08:21:38 UTC

Permalink

Post by ChenQi
wifi connection could be managed by wpa-supplicant.

Alternatively there is iwd (see [1]) which is heading towards version
1.0 in the coming weeks and is already supported by connman.

Post by ChenQi
Best Regards,
Chen Qi

Take a look at NetworkManager as a possible replacement of connman (see
[2]) - it also supports iwd. If NetworkManager and its dependencies is
too big for your project, perhaps managing the ethernet connections via
systemd-networkd and the wifi connections directly via iwd could be an
option (but needs more handwork).

Best regards
Ulrich

[1] https://layers.openembedded.org/layerindex/recipe/89268/
[2] https://layers.openembedded.org/layerindex/recipe/72479/

Post by ChenQi

Post by Mauro Ziliani
Best regards,
MZ

Herman van Hazendonk

2018-12-06 08:49:05 UTC

Permalink

Hi Mauro,

You can always try to get a newer version of connmand and dbus
integrated into your build. Often some of these issues are solved in a
newer version.

Thud provides 1.35
(https://github.com/openembedded/openembedded-core/tree/thud/meta/recipes-connectivity/connman)
and master 1.36
(https://github.com/openembedded/openembedded-core/tree/master/meta/recipes-connectivity/connman)
and dbus 1.12.10 from
https://github.com/openembedded/openembedded-core/tree/thud/meta/recipes-core/dbus

Best regards,
Herman

Burton, Ross

2018-12-06 10:21:50 UTC

Permalink

Post by Mauro Ziliani
Normally the sytstem works well. Sometimes, randomly, the system freeze
or the app crashes.
I made many test and this happens when the system is connected to a SSID.
So I suspect that the problem is in connamd_1.31+dbus_1.10.6

Connman is just a management tool, the actual work is done by other
pieces of the stack such as wpa_supplicant (actually tells the drivers
what to do) or the kernel drives themselves. Changing connman won't
change those, so it's fairly likely that the crashes will continue.
iwd is a future alternative for wpa_supplicant but I'm not sure it's
ready for production use just yet.

Instead of going from "bad things happen when on wifi" to "I blame
connman", step back and root-cause carefully. Is the kernel hanging?
Attach a remote gdb so you can identify why, or enable comprehensive
logging to a serial terminal so you can see any messages. Maybe your
wifi kernel driver is buggy. Is just the application hanging? Much
easier to debug, with gdb.

Ross
--