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 :
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 :
Then, further dig pointed some issues with the iwlwifi package not handling properly this version of the AC 7265. From lspci :
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) :
Now, if you check your dmesg, you’ll see :
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.