Hello.
On 31/07/15 00:52, Alexander Aring wrote:
On Thu, Jul 30, 2015 at 06:17:44PM +0200, Stefan Schmidt wrote:
Hello.
On 24/07/15 15:01, Alexander Aring wrote:
If we currently change the mac address inside the wpan interface while
we have a lowpan interface on top of the wpan interface, the mac address
setting doesn't reach the lowpan interface. The effect would be that the
IPv6 lowpan interface has the old SLAAC address and isn't working
anymore because the lowpan interface use in internal mechanism sometimes
dev->addr which is the old mac address of the wpan interface.
This patch checks if a wpan interface belongs to lowpan interface, if
yes then we need to check if the lowpan interface is down and change the
mac address also at the lowpan interface. When the lowpan interface will
be set up afterwards, it will use the correct SLAAC address which based
on the updated mac address setting.
Signed-off-by: Alexander Aring<alex.aring@xxxxxxxxx>
Reviewed-by: Stefan Schmidt<stefan@xxxxxxxxxxxxxxx>
I have a bit trouble testing it though. With iwpan we only allow to set the
short address while the extended address is set during device registration.
Removing this device also removes the connected lowpan device so I wonder
where we would run into this problem. Patch is fine in any case but having
1. have running lowpan setup
2. ifdown wpan only, let lowpan up
3. change mac (extended_addr) of wpan interface
4. do it up again
What confused me was that I had to get wpan and lowpan down. After that
the patches do as said. It does not work before but with the patches the
address gets updated.
I only found one little problem when wpan was down but lowpan up I would
set the new mac address and ip would error out but still set it for
wpan. Alex send me a small follow up patch which fixes that. Should come
squeezed in with that one as an update. With all this:
Tested-by: Stefan Schmidt <stefan@xxxxxxxxxxxxxxx>
-> something is wrong because the mac of lowpan isn't the same like wpan
anymore. We have several issues, maybe we could deal with that in
802.15.4 6LoWPAN code, but also the SLAAC address isn't right
anymore. IPv6 can deal with this address only when the interface is
down, because on ifup IPv6 on able interface -> the IPv6 stack will
generate the SLAAC address then according to the mac address.
What I mean in this case with "SLAAC" address is the standard
link-local address "fe:80::$EUI64_ADDRESS_WITH_UE_BIT/64"
As sidenote I have just seen that your patch subject is missing
something at the end. I think you meant:
mac802154: fix wpan mac setting while lowpan is up
or similar. Not sure if you want to re-spin for this.
regards
Stefan Schmidt
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