Lately I discovered an issue with my WiFi adapter on my professional laptop (a Lenovo T450) : it was not working. Pretty inconvenient. After some digging, I tested and had to adapt part of things I found on Google.

So, to begging with, the symptoms :

• no more wireless adapter in my NetworkManager or any other tools, including ifconfig
• dmesg reports issues loading the iwlwifi firmware

The dmesg output looks like :

[ 4.237444] iwlwifi 0000:03:00.0: Direct firmware load for iwlwifi-7265D-12.ucode failed with error -2
[ 4.237466] iwlwifi 0000:03:00.0: Direct firmware load for iwlwifi-7265D-11.ucode failed with error -2
[ 4.237479] iwlwifi 0000:03:00.0: Direct firmware load for iwlwifi-7265D-10.ucode failed with error -2
[ 4.237482] iwlwifi 0000:03:00.0: request for firmware file 'iwlwifi-7265D-10.ucode' failed.
[ 4.237493] iwlwifi 0000:03:00.0: Direct firmware load for iwlwifi-7265D-9.ucode failed with error -2
[ 4.237495] iwlwifi 0000:03:00.0: request for firmware file 'iwlwifi-7265D-9.ucode' failed.
[ 4.237497] iwlwifi 0000:03:00.0: no suitable firmware found!

I tried to download the official firmware from Intel, namely iwlwifi-7265-ucode-25.30.14.0, with no luck. Though, I decided to keep the ucode files from this archive in my /lib/firmware/.

Note that, depending on your distro, this previous step might be enough. To check :

update-initramfs -u
reboot

Then, further dig pointed some issues with the iwlwifi package not handling properly this version of the AC 7265. From lspci :

03:00.0 Network controller [0280]: Intel Corporation Wireless 7265 [8086:095b] (rev 59)
 Subsystem: Intel Corporation Dual Band Wireless-AC 7265 [8086:5210]

Here, the main points are the main ID 095b and the Subsystem ID 5210.

To solve this, let’s recompile the backport package of iwlwifi with a tiny difference (the sed line is to adapt with your IDs) :

sudo apt-get install build-essential linux-headers-$(uname -r)
wget https://www.dropbox.com/s/gyuvdlhzx5ho277/backports-20150731.tar.gz
tar -zxvf backports-20150731.tar.gz
cd backports-20150731/
sed -i 's/IWL_PCI_DEVICE(0x095B, 0x9200, iwl7265_2ac_cfg)/IWL_PCI_DEVICE(0x095B, 0x5212, iwl7265_2ac_cfg)/' drivers/net/wireless/iwlwifi/pcie/drv.c 
make defconfig-iwlwifi
make
sudo make install
update-initramfs -u
reboot

Now, if you check your dmesg, you’ll see :

[ 3.950804] iwlwifi 0000:03:00.0: Direct firmware load for iwlwifi-7265D-15.ucode failed with error -2
[ 3.952513] audit: type=1400 audit(1458119598.627:5): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/sbin/dhclient" pid=657 comm="apparmor_parser"
[ 3.952521] audit: type=1400 audit(1458119598.627:6): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=657 comm="apparmor_parser"
[ 3.952525] audit: type=1400 audit(1458119598.627:7): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/lib/connman/scripts/dhclient-script" pid=657 comm="apparmor_parser"
[ 3.953091] audit: type=1400 audit(1458119598.627:8): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=657 comm="apparmor_parser"
[ 3.953100] audit: type=1400 audit(1458119598.627:9): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="/usr/lib/connman/scripts/dhclient-script" pid=657 comm="apparmor_parser"
[ 3.953362] audit: type=1400 audit(1458119598.627:10): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="/usr/lib/connman/scripts/dhclient-script" pid=657 comm="apparmor_parser"
[ 3.955605] iwlwifi 0000:03:00.0: loaded firmware version 25.30.14.0 op_mode iwlmvm
[ 3.975336] input: ThinkPad Extra Buttons as /devices/platform/thinkpad_acpi/input/input7
[ 4.001495] iwlwifi 0000:03:00.0: Detected Intel(R) Dual Band Wireless AC 7265, REV=0x210
[ 4.001843] iwlwifi 0000:03:00.0: L1 Enabled - LTR Enabled
[ 4.002290] iwlwifi 0000:03:00.0: L1 Enabled - LTR Enabled

And, voilà, your wireless adapter is back online !

NB: you’ll have to redo these steps after every kernel update, except if the iwlwifi module got fixed.

The post Lenovo T450 Wireless AC 7265 not working on Linux appeared first on Here and Now ... Then and There.

Original post of Francois Aichelbaum.Votez pour ce billet sur Planet Libre.