prevent bluetooth from loading (manjaro, no wifi/bt card installed)

prevent bluetooth from loading (manjaro, no wifi/bt card installed) - Printable Version

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+--- Thread: prevent bluetooth from loading (manjaro, no wifi/bt card installed) (/showthread.php?tid=16115)

prevent bluetooth from loading (manjaro, no wifi/bt card installed) - flounder - 02-17-2022

Running Manjaro (new install this week, manjaro build for rockpro64, v21.12). I do *not* have the wifi/bt card installed

I'm attempting to triage a different failure, but bluetooth messages are all over dmesg. Since i don't plan on using BT at all, i'd just like to prevent whoever is writing that from loading:

Code:
$ dmesg

...

[  11.202048] Bluetooth: HCI UART driver ver 2.3

...

[  13.143625] Bluetooth: BNEP socket layer initialized

[  13.512037] Bluetooth: hci0: command 0x0c03 tx timeout

Code:
$ lsmod | grep -i hci

hci_uart              147456  0

btqca                  24576  1 hci_uart

btrtl                  24576  1 hci_uart

btbcm                  28672  1 hci_uart

btintel                45056  1 hci_uart

bluetooth            679936  13 btrtl,btqca,btintel,hci_uart,btbcm,bnep

Code:
$ journalctl -u bluetooth.service

-- Boot ec6359ece9924fb69d0a0fe601e1c991 --

Feb 16 20:30:54 mypc systemd[1]: Starting Bluetooth service...

Feb 16 20:30:54 mypc bluetoothd[612]: Bluetooth daemon 5.63

Feb 16 20:30:54 mypc systemd[1]: Started Bluetooth service.

Feb 16 20:30:54 mypc bluetoothd[612]: Starting SDP server

Feb 16 20:30:54 mypc bluetoothd[612]: Bluetooth management interface 1.21 initialized

Feb 16 21:08:10 mypc bluetoothd[612]: Terminating

Feb 16 21:08:10 mypc bluetoothd[612]: Stopping SDP server

what's the RIGHT way to disable this in manjaro? Looks like there are several obvious modules I could blacklist, and the `systemd` service. I'm new to Manjaro, looking for the "standard" / maintainable / stable over rolling upgrade way. It also seems confusing to me that the `bluetooth` service isn't failing, or at least immediately exiting, given there is no HW present.

Thanks!

One of the reasons I'm asking how to do this correctly, rather than just blacklist (presumably would prevent these ringlog messages) or disable with systemctl, is that I'd like to understand the modules are loaded in the first place.

I'm no linux expert, but have been daily driving for some time. My limited understanding would expect that (for the bluetooth/bt* modules to be loaded, they would have to be ONE of

some HW present, which at kernel boot would be probed, and udev would later load the module based on HW id's (again, no HW connected AFAIK)
have an explicit load in /etc/modules-load.d (I have zero files there)
be an explicit kernel param in grub (nothing in /proc/cmdline)

Are there other ways that those modules would get loaded automatically at boot?