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802.15.4 6LoWPAN fragmentation is broken

DISCUSSION Alexander Aring 1 participant 2 messages Jan 13, 2015 – Jan 14, 2015 IEEE 802.15.4

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Alexander Aring

author maintainer
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Hi,

I notice some issue with fragmentation code.

There is some magic number like:

ping6 2001::1 -s 2145

with a payload of 2144 it works. It seems that all payloads above 2144 are broken. I will try to bisect this issue. I see this issue also in net-next. I suppose it's something with the inet_frag API.

... so don't worry I already working on it.

- Alex

author maintainer
#1 lore raw

Hi,

Quoted 6 lines · Alexander Aring

Hi,

I notice some issue with fragmentation code.

There is some magic number like:

Quoted 9 lines

ping6 2001::1 -s 2145

with a payload of 2144 it works. It seems that all payloads above 2144 are broken. I will try to bisect this issue. I see this issue also in net-next. I suppose it's something with the inet_frag API.

... so don't worry I already working on it.

Status update to this:

I detected that systemd changed the default net scheduler to fq_codel. [0] With fq_codel seems that 6LoWPAN fragmentation is broken.

For now: please don't use this scheduler. I will try to find out why we have fragmentation issues with fq_codel.

- Alex

[0] http://cgit.freedesktop.org/systemd/systemd/commit/?id=e6c253e363dee77ef7e5c5f44c4ca55cded3fd47