tl;dr 我关闭了蓝牙，但它无法重新打开。
我已经运行 Ubuntu 16.04 LTS 大约六个月了，蓝牙一直运行正常。我一直使用蓝牙与 Logitech M555b 鼠标，没有任何问题。我最近购买了另一款蓝牙鼠标（Logitech T630），成功设置后，它变得非常滞后且不稳定。
我关闭了蓝牙并且它无法重新打开。（我使用系统设置>蓝牙下的切换开关将其关闭）我花了两天时间尝试重新打开蓝牙，但没有成功。
蓝牙图标已从顶部菜单栏消失，并且不会再出现。我尝试使用“系统设置”>“蓝牙”下的切换按钮重新打开蓝牙，起初它会切换到“开”并变成橙色，但菜单图标不会返回，关闭“设置”并重新打开后，它会回到“关”的位置。
当我的蓝牙仍然在“rfkill list all”下显示为“hci0”（没有软阻止）时，就会发生这种情况。现在它在“rfkill list all”下根本不显示，并且系统设置 > 蓝牙下的所有选项（包括切换开关）都变灰了。
我尝试过的事情：
- ‘sudo /etc/init.d/bluetooth 重启’
- ‘sudo modprobe btusb’
- '通过 Synaptic 重新安装所有蓝牙相关软件包
- ‘rfkill unblock hci0’（当蓝牙显示在‘rfkill list all’下时，即使没有软阻止，但‘hci0’不再显示在‘rfkill list all’下
- ‘rfkill 解除全部阻止’
- ‘sudo apt-get 安装——重新安装 bluez’
- 'sudo hciconfig hci0 reset' & 'sudo hciconfig hci0 up'（之前 hci0 还出现，但现在 hci0 已经消失了）
- ‘sudo 服务蓝牙停止’ & ‘sudo 服务蓝牙启动’
- 安装“蓝牙”包
- 安装“blueman”包（运行此应用程序确实暂时恢复了菜单栏中的蓝牙图标，但其所有选项均不起作用）
- ‘sudo mv /etc/bluetooth /etc/bluetooth.backup’
- 多次重启和关机
我读过几十个与 Ubuntu 中的蓝牙问题相关的链接，但都不起作用。我不认为这是重复的。以下是我尝试从中寻找解决方案的一些链接：
- askubuntu.com/questions/286834/bluetooth-not-working-in-ubuntu-13-04
- ubuntuforums.org/showthread.php?t=2324071
- ubuntuforums.org/showthread.php?t=2219575
- askubuntu.com/questions/758778/ubuntu-15-10-bluetooth-no-adapters-found?noredirect=1&lq=1
- askubuntu.com/questions/474839/bluetooth-is-disable-on-ubuntu-14-04
- askubuntu.com/questions/614319/ubuntu-15-04-bluetooth-no-adapters-found-dell-precision-m4800
- ubuntuforums.org/showthread.php?t=1546007
还有更多，但它不允许发布链接，因为我是该网站的新人。
以下是一些不同的输出：
$ lsusb
Bus 002 Device 002: ID 8087:8001 Intel Corp.
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:8009 Intel Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 003: ID 1c4f:0032 SiGma Micro
Bus 003 Device 002: ID 04d9:0161 Holtek Semiconductor, Inc.
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
$ rfkill 列出全部
0: phy0: Wireless LAN
Soft blocked: yes
Hard blocked: no
$ lspci -knn | grep Net -A2; lsusb
03:00.0 Network controller [0280]: Intel Corporation Wireless 7260 [8086:08b1] (rev 73)
Subsystem: Intel Corporation Dual Band Wireless-AC 7260 [8086:4070]
Kernel driver in use: iwlwifi
Bus 002 Device 002: ID 8087:8001 Intel Corp.
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:8009 Intel Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 003: ID 1c4f:0032 SiGma Micro
Bus 003 Device 002: ID 04d9:0161 Holtek Semiconductor, Inc.
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
$“hciconfig -a”未返回任何内容
$ lsmod
Module Size Used by
bluetooth 520192 0
xt_multiport 16384 2
iptable_filter 16384 1
ip_tables 24576 1 iptable_filter
x_tables 36864 3 ip_tables,xt_multiport,iptable_filter
input_leds 16384 0
pci_stub 16384 1
vboxpci 24576 0
vboxnetadp 28672 0
vboxnetflt 28672 0
vboxdrv 454656 3 vboxnetadp,vboxnetflt,vboxpci
snd_hda_codec_hdmi 53248 1
arc4 16384 2
nls_iso8859_1 16384 1
intel_rapl 20480 0
x86_pkg_temp_thermal 16384 0
intel_powerclamp 16384 0
coretemp 16384 0
kvm_intel 172032 0
kvm 540672 1 kvm_intel
snd_hda_codec_realtek 86016 1
snd_hda_codec_generic 77824 1 snd_hda_codec_realtek
iwlmvm 311296 0
irqbypass 16384 1 kvm
snd_hda_intel 40960 5
mac80211 737280 1 iwlmvm
crct10dif_pclmul 16384 0
crc32_pclmul 16384 0
snd_hda_codec 135168 4 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_codec_generic,snd_hda_intel
snd_soc_rt5640 114688 0
snd_hda_core 73728 5 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_codec_generic,snd_hda_codec,snd_hda_intel
snd_hwdep 16384 1 snd_hda_codec
snd_soc_ssm4567 16384 0
snd_soc_rl6231 16384 1 snd_soc_rt5640
iwlwifi 200704 1 iwlmvm
aesni_intel 167936 0
aes_x86_64 20480 1 aesni_intel
lrw 16384 1 aesni_intel
gf128mul 16384 1 lrw
glue_helper 16384 1 aesni_intel
snd_soc_core 212992 2 snd_soc_rt5640,snd_soc_ssm4567
ablk_helper 16384 1 aesni_intel
cryptd 20480 2 aesni_intel,ablk_helper
snd_compress 20480 1 snd_soc_core
ac97_bus 16384 1 snd_soc_core
snd_pcm_dmaengine 16384 1 snd_soc_core
snd_pcm 106496 7 snd_soc_rt5640,snd_soc_core,snd_hda_codec_hdmi,snd_hda_codec,snd_hda_intel,snd_pcm_dmaengine,snd_hda_core
serio_raw 16384 0
cfg80211 565248 3 iwlwifi,mac80211,iwlmvm
snd_seq_midi 16384 0
lpc_ich 24576 0
snd_seq_midi_event 16384 1 snd_seq_midi
shpchp 36864 0
mei_me 36864 0
snd_rawmidi 32768 1 snd_seq_midi
mei 98304 1 mei_me
snd_seq 69632 2 snd_seq_midi_event,snd_seq_midi
snd_seq_device 16384 3 snd_seq,snd_rawmidi,snd_seq_midi
snd_timer 32768 2 snd_pcm,snd_seq
snd 81920 23 snd_hda_codec_realtek,snd_soc_core,snd_hwdep,snd_timer,snd_hda_codec_hdmi,snd_pcm,snd_seq,snd_rawmidi,snd_hda_codec_generic,snd_hda_codec,snd_hda_intel,snd_seq_device,snd_compress
dw_dmac 16384 0
snd_soc_sst_acpi 16384 0
dw_dmac_core 24576 1 dw_dmac
elan_i2c 36864 0
8250_fintek 16384 0
soundcore 16384 1 snd
i2c_designware_platform 16384 0
i2c_designware_core 20480 1 i2c_designware_platform
8250_dw 16384 0
acpi_pad 20480 0
spi_pxa2xx_platform 24576 0
mac_hid 16384 0
parport_pc 32768 0
ppdev 20480 0
lp 20480 0
parport 49152 3 lp,ppdev,parport_pc
autofs4 40960 2
hid_generic 16384 0
usbhid 49152 0
i915 1208320 4
i2c_algo_bit 16384 1 i915
drm_kms_helper 155648 1 i915
syscopyarea 16384 1 drm_kms_helper
sysfillrect 16384 1 drm_kms_helper
sysimgblt 16384 1 drm_kms_helper
fb_sys_fops 16384 1 drm_kms_helper
psmouse 126976 0
drm 364544 5 i915,drm_kms_helper
e1000e 237568 0
ahci 36864 4
ptp 20480 1 e1000e
libahci 32768 1 ahci
alx 36864 0
pps_core 20480 1 ptp
mdio 16384 1 alx
video 40960 1 i915
sdhci_acpi 16384 0
i2c_hid 20480 0
sdhci 45056 1 sdhci_acpi
hid 118784 3 i2c_hid,hid_generic,usbhid
fjes 28672 0
$ lspci -nnk | grep -iA2 net; lsusb; lsmod | grep blue; dmesg | egrep -i'blue|firm'
00:19.0 Ethernet controller [0200]: Intel Corporation Ethernet Connection I217-V [8086:153b]
DeviceName: Onboard LAN
Subsystem: Gigabyte Technology Co., Ltd Ethernet Connection I217-V [1458:e000]
Kernel driver in use: e1000e
Kernel modules: e1000e
--
02:00.0 Ethernet controller [0200]: Qualcomm Atheros AR8161 Gigabit Ethernet [1969:1091] (rev 10)
Subsystem: Gigabyte Technology Co., Ltd AR8161 Gigabit Ethernet [1458:e000]
Kernel driver in use: alx
Kernel modules: alx
03:00.0 Network controller [0280]: Intel Corporation Wireless 7260 [8086:08b1] (rev 73)
Subsystem: Intel Corporation Dual Band Wireless-AC 7260 [8086:4070]
Kernel driver in use: iwlwifi
Bus 002 Device 002: ID 8087:8001 Intel Corp.
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:8009 Intel Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 003: ID 1c4f:0032 SiGma Micro
Bus 003 Device 002: ID 04d9:0161 Holtek Semiconductor, Inc.
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
bluetooth 520192 0
[ 2.142805] iwlwifi 0000:03:00.0: Direct firmware load for iwlwifi-7260-17.ucode failed with error -2
[ 2.146406] iwlwifi 0000:03:00.0: loaded firmware version 16.242414.0 op_mode iwlmvm
[ 1658.082516] Bluetooth: Core ver 2.21
[ 1658.082530] Bluetooth: HCI device and connection manager initialized
[ 1658.082533] Bluetooth: HCI socket layer initialized
[ 1658.082535] Bluetooth: L2CAP socket layer initialized
[ 1658.082538] Bluetooth: SCO socket layer initialized
感谢您提供的任何帮助，蓝牙两天前还可以正常工作，我迫切希望它再次正常工作。