Bluetooth Linux issue

[Linus Torvalds]

On Mon, Feb 1, 2016 at 7:25 PM, Stephen Hemminger
<stephen at networkplumber.org> wrote:
>
> The workaround was to manually stop the service with:
>  $ sudo service ModemManager stop

I thought we already documented that for normal serial ports, because
ModemManager has screwed up those too. But a quick grep doesn't show
anything, so I suspect it was just discussed on the list a long long
time ago. I have some emails from three years ago talking about
modem-manager screwing up downloads.

In fact, the right thing to do tends to be not just to "stop"
ModemManager, but to disable it entirely. Preferably by uninstalling
it. I know I used to just force-uninstall it, because I got so fed up
with it accessing the serial ports randomly.

If somebody actually likes and finds MM useful, you apparently _can_
also mark devices as "don't touch" in the udev rules:

    http://lists.hohndel.org/pipermail/subsurface/2013-June/006687.html

But I've never seen a situation where ModemManager helped, and it
definitely has hurt with regular serial lines (and apparently now also
BT).

                      Linus