Fedora 40 and the case of the missing wifi

I’ve out-of-the-box transformed enough machines from Windows and MacOS to Linux that missing wifi is no great surprise. What is, however, an extremely unpleasant surprise is when functional wifi goes missing, as it has during the transition to Fedora 40. As it turns out, this is not such a big problem to fix, but isolating the issue itself was difficult. For the record, I had stable wifi on two 2015 Macs (one MacBook pro, one Air) both with Broadcom network chips, which are known to be finicky.

Turns out in Fedora 40, MAC addresses are now stable. Good for privacy, but bad for my immediate wifi setup.

Turns out the fix is not so bad. First, check chipset details to make sure chip is discoverable:

lspci | grep Network

output should reference chipset (e.g., 03:00.0 Network controller: Broadcom Inc. and subsidiaries BCM43602 802.11ac Wireless LAN SoC (rev 01))

And wpa_supplicant is not yet matched with stable paradigm for MAC addresses, so downgrade it:

sudo dnf downgrade wpa_supplicant

Then reboot except as a hard reboot — aka, power off machine and then power back on, without continuous reboot.

More information / original source: https://discussion.fedoraproject.org/t/wifi-networks-not-showing-up-in-setting-panel/127924/3