Guys!
Don't forget I can test it - since I have a remote machine with 3.16 kernel 
and the device, at least for now.
So - Bjorn: do I need just to disable padding or do I need also to perform some 
other changes? I am sorry if I ask this a little bit stupidly, but I was 
alittle bit busy here.





On Thu, 4 Dec 2014, Bjørn Mork wrote:

Date: Thu, 4 Dec 2014 10:19:11
From: Bjørn Mork <bjorn@mork.no>
To: Kevin Zhu <redacted>
Cc: Enrico Mioso <redacted>,
    Eli Britstein [off-list ref],
    Alex Strizhevsky [off-list ref],
    Midge Shaojun Tan [off-list ref],
    "youtux@gmail.com" [off-list ref],
    "linux-usb@vger.kernel.org" [off-list ref],
    "netdev@vger.kernel.org" [off-list ref]
Subject: Re: Is this 32-bit NCM?y

Kevin Zhu [off-list ref] writes:

quoted

Guys,

After rearranging the padding, putting NCM0 right after NTH, and disable
ARP (FLAG_NOARP) and handling the offset alignment issue, it seems it
begins to work, though there's still problem with DHCP.

Great!  But it would be good to know if _one_ of these changes is enough
to make it work.

quoted

The DHCP packet's size becomes a large one after the TX function, which
is 16384, the maximum.

You can now (from v3.16) disable the padding by setting min_tx_pkt >= tx_max.
Something like this should do for a simple test:

echo 16384 >/sys/class/net/wwan0/cdc_ncm/min_tx_pkt


Bjørn