在 Ubuntu 18.04 上打开蓝牙后，无法搜索任何设备。
我跑了rfkill list，一切都畅通了。
rfkill list all
0: dell-rbtn: Wireless LAN
Soft blocked: no
Hard blocked: no
1: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
2: brcmwl-0: Wireless LAN
Soft blocked: no
Hard blocked: no
3: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
实际上，在查看蓝牙状态时，我收到了 rfkill 错误
$ /etc/init.d/bluetooth status
bluetooth.service - Bluetooth service
Loaded: loaded (/lib/systemd/system/bluetooth.service; enabled; vendor preset: enabled)
Active: active (running) since Fri 2019-12-27 13:12:47 IST; 5min ago
Docs: man:bluetoothd(8)
Main PID: 940 (bluetoothd)
Status: "Running"
Tasks: 1 (limit: 4915)
CGroup: /system.slice/bluetooth.service
└─940 /usr/lib/bluetooth/bluetoothd
Dec 27 13:12:47 shubham-Inspiron-3542 bluetoothd[940]: Bluetooth daemon 5.50
Dec 27 13:12:47 shubham-Inspiron-3542 bluetoothd[940]: Starting SDP server
Dec 27 13:12:47 shubham-Inspiron-3542 bluetoothd[940]: Bluetooth management interface 1.14 initialized
Dec 27 13:12:47 shubham-Inspiron-3542 bluetoothd[940]: Failed to set mode: Blocked through rfkill (0x12)
Dec 27 13:12:47 shubham-Inspiron-3542 systemd[1]: Starting Bluetooth service...
Dec 27 13:12:47 shubham-Inspiron-3542 systemd[1]: Started Bluetooth service.
Dec 27 13:12:57 shubham-Inspiron-3542 bluetoothd[940]: Failed to set mode: Blocked through rfkill (0x12)
Dec 27 13:13:32 shubham-Inspiron-3542 bluetoothd[940]: Endpoint registered: sender=:1.81 path=/MediaEndpoint/A2DPSource
Dec 27 13:13:32 shubham-Inspiron-3542 bluetoothd[940]: Endpoint registered: sender=:1.81 path=/MediaEndpoint/A2DPSink
Dec 27 13:13:36 shubham-Inspiron-3542 bluetoothd[940]: Failed to set mode: Blocked through rfkill (0x12)
请帮忙。我甚至尝试更新固件，但问题还是没有解决。