I'm working on Dell Latitude 7480 laptop with Ubuntu 14.04. The current kernel version I'm using is v4.4.0.116-generic. The WiFi does not work at the moment. I followed the instructions given here- Intel WiFi Card Not Recognised in Ubuntu 16.04 and the WiFi did work briefly. But when I upgrade the kernel to v4.10 or v4.11 the system stops working but the WiFi connections are available. The WiFi does not work for v4.5.
The output of the network diagnosis script is given below-
########## wireless info START ##########
Report from: 13 Mar 2018 15:27 GMT +0000
Booted last: 13 Mar 2018 14:49 GMT +0000
Script from: 10 Jan 2018 20:04 UTC +0000
##### release ###########################
Distributor ID: Ubuntu
Description: Ubuntu 14.04.5 LTS
Release: 14.04
Codename: trusty
##### kernel ############################
Linux 4.4.0-116-generic #140~14.04.1-Ubuntu SMP Fri Feb 16 09:25:20 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
Parameters: ro, quiet, splash, vt.handoff=7
##### desktop ###########################
Ubuntu
##### lspci #############################
00:1f.6 Ethernet controller [0200]: Intel Corporation Device [8086:15d7] (rev 21)
Subsystem: Dell Device [1028:07a0]
Kernel driver in use: e1000e
02:00.0 Network controller [0280]: Intel Corporation Device [8086:24fd] (rev 78)
Subsystem: Intel Corporation Device [8086:0050]
##### lsusb #############################
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 0bda:5650 Realtek Semiconductor Corp.
Bus 001 Device 004: ID 0a5c:5832 Broadcom Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
##### PCMCIA card info ##################
##### rfkill ############################
1: dell-wifi: Wireless LAN
Soft blocked: no
Hard blocked: no
2: dell-bluetooth: Bluetooth
Soft blocked: yes
Hard blocked: no
##### lsmod #############################
dell_wmi 16384 0
dell_laptop 20480 0
dcdbas 16384 1 dell_laptop
wmi 20480 2 dell_led,dell_wmi
video 40960 3 i915_bpo,dell_wmi,dell_laptop
sparse_keymap 16384 2 dell_wmi,intel_hid
##### interfaces ########################
[/etc/network/interfaces]
auto lo
iface lo inet loopback
##### ifconfig ##########################
eth0 Link encap:Ethernet HWaddr <MAC 'eth0' [IF1]>
inet addr:172.22.70.173 Bcast:172.22.255.255 Mask:255.255.0.0
inet6 addr: fe80::<IP6 'eth0' [IF1]>/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:272874 errors:0 dropped:0 overruns:0 frame:0
TX packets:24057 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:97183114 (97.1 MB) TX bytes:3638783 (3.6 MB)
Interrupt:16 Memory:ef200000-ef220000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:4208 errors:0 dropped:0 overruns:0 frame:0
TX packets:4208 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1
RX bytes:408782 (408.7 KB) TX bytes:408782 (408.7 KB)
##### iwconfig ##########################
lo no wireless extensions.
eth0 no wireless extensions.
##### route #############################
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.22.1.1 0.0.0.0 UG 0 0 0 eth0
172.22.0.0 0.0.0.0 255.255.0.0 U 1 0 0 eth0
##### resolv.conf #######################
nameserver 127.0.1.1
search windows.ebi.ac.uk ebi.ac.uk
##### network managers ##################
Installed:
NetworkManager
Running:
root 774 1 0 14:49 ? 00:00:00 NetworkManager
##### NetworkManager info ###############
NetworkManager Tool
State: connected (global)
- Device: eth0 [Wired connection 1] -------------------------------------------
Type: Wired
Driver: e1000e
State: connected
Default: yes
HW Address: <MAC 'eth0' [IF1]>
Capabilities:
Carrier Detect: yes
Speed: 1000 Mb/s
Wired Properties
Carrier: on
IPv4 Settings:
Address: 172.22.70.173
Prefix: 16 (255.255.0.0)
Gateway: 172.22.1.1
DNS: 172.22.2.8
DNS: 172.22.2.10
DNS: 172.22.2.9
##### NetworkManager.state ##############
[main]
NetworkingEnabled=true
WirelessEnabled=true
WWANEnabled=true
WimaxEnabled=true
##### NetworkManager.conf ###############
[main]
plugins=ifupdown,keyfile,ofono
dns=dnsmasq
[ifupdown]
managed=false
##### NetworkManager profiles ###########
[[/etc/NetworkManager/system-connections/VM380140-5G]] (600 root)
[connection] id=VM380140-5G | type=802-11-wireless
[802-11-wireless] ssid=VM380140-5G | mac-address=<MAC address>
[ipv4] method=auto
[ipv6] method=auto
[[/etc/NetworkManager/system-connections/EBI]] (600 root)
[ipv6] method=auto
[connection] id=EBI | type=802-11-wireless
[802-11-wireless] ssid=EBI | mac-address=<MAC address>
[ipv4] method=auto
##### Netplan config ####################
##### iw reg get ########################
Region: Europe/London (based on set time zone)
country 00:
(2402 - 2472 @ 40), (6, 20)
(2457 - 2482 @ 40), (6, 20), PASSIVE-SCAN
(2474 - 2494 @ 20), (6, 20), NO-OFDM, PASSIVE-SCAN
(5170 - 5250 @ 160), (6, 20), PASSIVE-SCAN
(5250 - 5330 @ 160), (6, 20), DFS, PASSIVE-SCAN
(5490 - 5730 @ 160), (6, 20), DFS, PASSIVE-SCAN
(5735 - 5835 @ 80), (6, 20), PASSIVE-SCAN
(57240 - 63720 @ 2160), (N/A, 0)
##### iwlist channels ###################
lo no frequency information.
eth0 no frequency information.
##### iwlist scan #######################
lo Interface doesn't support scanning.
eth0 Interface doesn't support scanning.
##### module infos ######################
##### module parameters #################
##### /etc/modules ######################
lp
rtc
##### modprobe options ##################
[/etc/modprobe.d/blacklist-ath_pci.conf]
blacklist ath_pci
[/etc/modprobe.d/blacklist.conf]
blacklist evbug
blacklist usbmouse
blacklist usbkbd
blacklist eepro100
blacklist de4x5
blacklist eth1394
blacklist snd_intel8x0m
blacklist snd_aw2
blacklist i2c_i801
blacklist prism54
blacklist bcm43xx
blacklist garmin_gps
blacklist asus_acpi
blacklist snd_pcsp
blacklist pcspkr
blacklist amd76x_edac
[/etc/modprobe.d/blacklist-rare-network.conf]
alias net-pf-3 off
alias net-pf-6 off
alias net-pf-9 off
alias net-pf-11 off
alias net-pf-12 off
alias net-pf-19 off
alias net-pf-21 off
alias net-pf-36 off
[/etc/modprobe.d/iwlwifi.conf]
remove iwlwifi \
(/sbin/lsmod | grep -o -e ^iwlmvm -e ^iwldvm -e ^iwlwifi | xargs /sbin/rmmod) \
&& /sbin/modprobe -r mac80211
[/etc/modprobe.d/mlx4.conf]
softdep mlx4_core post: mlx4_en
##### rc.local ##########################
exit 0
##### pm-utils ##########################
##### udev rules ########################
[/etc/udev/rules.d/70-persistent-net.rules]
# PCI device 0x8086:0x15d7 (e1000e)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="<MAC 'eth0' [IF1]>", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
# PCI device 0x8086:0x24fd (iwlwifi)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="<MAC address>", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="wlan*", NAME="wlan0"
##### dmesg #############################
[ 3.924048] i915_bpo 0000:00:02.0: Direct firmware load for i915/kbl_dmc_ver1.bin failed with error -2
[ 3.924053] i915_bpo 0000:00:02.0: Failed to load DMC firmware [https://01.org/linuxgraphics/intel-linux-graphics-firmwares], disabling runtime power management.
[ 4.551782] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 7.362110] e1000e: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: Rx/Tx
[ 7.362145] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[ 1823.660741] e1000e: eth0 NIC Link is Down
[ 1865.597690] e1000e: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: Rx/Tx
########## wireless info END ############
Is there any driver I can install or upgrade the kernel to a version where WiFi does work but the system does not stop working?