ANN: ModemManager 1.18.4 released

[Dan Williams]

On Mon, 2021-11-29 at 10:52 -0500, Peter Naulls wrote:
> On 11/26/21 4:52 AM, Aleksander Morgado wrote:
> > Hey hey,
> > 
> > This is the second bugfix release in the 1.18.x series, built from
> > the mm-1-18 
> > branch.
> > 
> 
> Thanks!
> 
> I've been chasing, as I mentioned a while ago, where "sometimes" the
> modem 
> connection will be brought up as PPP, not qmi. This kind of
> connection fails
> in our setup for a bunch of reasons, and is not desirable.
> 
> I know that PPP is woven into ModemManager for several reasons, and
> building
> without is some work - I've seen several prior discussions on this
> topic.
> 
> I'm using a custom version of OpenWrt which is approximately the
> current
> release. I've mitigated the problem somewhat by removing the PPP
> connection
> scripts (/lib/netif/ppp*), which helps a little.  I'm using
> ModemManager
> 1.18.2 presently, which seems to work pretty well against kernel
> 4.14.256.
> Some versions of the kernel (perhaps due to timing or whatever) seem
> to
> trigger the problem more often, although it's hard to confirm that
> one
> way or another.
> 
> The QMI driver I have is highly customized, and may well be the root
> of the
> problem - recent kernels seem to have some validation around USB
> devices
> and whatnot.
> 
> In any case, I tested 1.18.4 today, and 100% of the time the
> connection
> now comes up in PPP.  It's not clear from the changes why this might
> now happen - perhaps there's extra validation or something.  But I'd
> really like to get to the bottom of this - any suggestions in the
> current
> changes that I should look at?

Do you have debug logs from MM? At the very least MM has to find a
netdevice for the modem, otherwise it would fall back to an available
AT port for PPP. Does MM find one?

Dan