Re: Sierra Wireless MC7750 / MM 0.7.990 / NM 0.9.8

[Bjørn Mork <bjorn mork no>]

Dan Williams <dcbw redhat com> writes:
> On Wed, 2013-05-22 at 14:58 +0200, Aleksander Morgado wrote:
> > On 05/22/2013 01:42 PM, Heiher wrote:
> > > It's connect to EVDO (China Telecom).
> > >
> > > Now, It works very well by legacy PPP mode (disable QMI, sudo modprobe
> > > -r qmi-wwan). It's kernel bug?
> >
> > Well, it should better work in QMI mode if possible. If the connection
> > worked in LTE using QMI but you still were not able to ping any IP
> > address, it may have been a known kernel issue.
>
> Yeah, I'll bet this is the kernel issue that Bjorn fixed to work around
> various quirks that QMI has.

Yes, could very well be.  The "DHCP works, but cannot ping" sounds just
like the missing ethernet header problem.

>  The patches are in the 3.9 kernel, and
> have been backported to the stable 3.4.46 kernel as well.  I'm not sure
> about the status for other "stable" kernel versions.
>
> The patches are:
>
> net: qmi_wwan: prevent duplicate mac address on link (firmware bug
> workaround)
> net: qmi_wwan: fixup destination address (firmware bug workaround)
> net: qmi_wwan: fixup missing ethernet header (firmware bug workaround)

They are currently in the v3.5 queue:
http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=history;f=drivers/net/usb/qmi_wwan.c;hb=linux-3.5.y-queue

Doesn't look like they are in the v3.8 longterm queue just yet, but I
assume they will be.


Bjørn