Le 13 juil. 2015 3:44 PM, Thomas B. Rücker <thomas@ruecker.fi> a écrit :
>
> Hi,
>
> On 07/13/2015 11:41 AM, Nicolas Dechesne wrote:
> > Le 13 juil. 2015 12:44 PM, Thomas B. Rücker <thomas@ruecker.fi> a écrit :
> >> After some unrelated delay, I have started using my Dragonboard. I
> >> downloaded a Linaro customized Ubuntu image:
> >> dragonboard410c_sdcard_install_ubuntu-40-47.zip
> >> from:
> >> http://builds.96boards.org/releases/dragonboard410c/linaro/ubuntu/latest/
> >>
> >> I was very surprised to find out that the IP network stack is broken on
> >> this image (cf. RFC 6540). The Kernel has been built with IPv6 disabled.
> >> This means I can't reach a substantial part of my test network and my
> >> production systems.
> >>
> >> Who at LINARO do I need to poke to get this fixed?
> > To me ... or to bugs.96boards.org
>
> Ah, good. :-)
>
>
> > This is something that will be fixed in July release, and already fixed in
> > our daily builds, can you inspect our current kernel config [1] and let us
> > know if that fixes your issues.
> >
> > [1]
> > http://builds.96boards.org/snapshots/dragonboard410c/linaro/ubuntu/latest/kernel.config
>
> Skimmed the config, looked OK. Found the images in the same directory
> flashed them.

Thanks!

>
> Good news:
> Yes the kernel knows about IPv6.
> The interfaces come up with link local addresses from within fe80::/64.
>
> Bad news:
> Something horribly breaks the network behaviour of this board.
> It does NOT acquire a routed IPv6 prefix through stateless auto
> configuration.
> It doesn't even see the route advertisements (checked by installing
> 'radvd' and running 'radvdump'). Other devices on the network use those
> without issue.
> The IPv6 link local address is NOT reachable over ICMPv6.
> It becomes reachable by _one_ node at a time by pinging that node _from_
> the device.
> Actually the same behaviour can be observed for legacy IPv4 too. You
> can't ping the device until the Dragonboard has pinged that particular
> machine and its address first.
>
> I'm not going to bother explaining how broken such network behaviour is,
> it's rather obvious. Time to get a USB ethernet adaptor from my drawer.
>
> Is there anything I can do to the wifi driver to fix this? Like
> disabling all optimizations and power saving? I highly suspect this is
> one of those optimized until useless for anything than an Android phone
> in its basic use case drivers.

The wlan driver we use is wcn36xx from mainline, it's a reverse eng driver, not a qcom driver, and not used in any android product:

https://wireless.wiki.kernel.org/en/users/drivers/wcn36xx

While the driver is still WIP , at least we can engage with upstream and hope to fix issues.. I am not working this week.. But will get back on that next week.

>
> Thomas
>
> PS: I'm also available for chat on #96boards on freenode IRC, but it's a
> rather dead channel it seems.
>