Buetooth DUN vs. suspend

[Galaxis]

In the recent days, I've been using an Android (Cyanogenmod 12.1) phone with bluetooth tethering as kind of an external 5GHz wifi card. This works quite well out of the box - when Pandora and phone are paired, Network Manager sees the PANU connection, and Android seems to do masquerading and DNS forwarding.

The only problem is that I cannot reconnect the link after the Pandora has been suspended, even if I completely disable BT and switch it back on. It does work when I disable BT, manually unload all the bluetooth modules (rfcomm bnep hci_uart bluetooth, not neccessarily in that order), and then reenable BT again.

So, is disabling BT through the control panel supposed to remove the kernel modules and it just doesn't work? Should suspend also unload the BT modules?

Btw., this seems to eat quite a bit of resourcs when the network is fast, but I don't expect anything can be done about that:

PID  USER PR  NI VIRT RES SHR S %CPU %MEM TIME+  COMMAND
3694 root -51 0  0  0  0  S 64.0 0.0  11:27.40 irq/72-serial i

 

[DAP]

I have found that it is impossible to connect to my bluetooth GPS after the Pandora has been suspended/hibernated, and I must disable then re-enable bluetooth before it will work again. I don't need to manually unload any modules though.

 

[notaz]

The suspend of UART (where BT is connected on pandora) is problematic on 3.2 kernel, this has been reported before. I don't use BT for anything and haven't really attempted to debug this.