My own WiFi SSID not appearing when using Hardened Kernel

I installed the Hardened Kernel shortly after installing EndeavourOS & faced no issues using it. Today after installing updates which included a new version of the Hardened Kernel & rebooting I found that my WiFi is not connected. When I clicked on the Network Manager icon on the sys tray I found 2 other SSIDs but surprisingly my own router’s SSID is missing. I thought that my WiFi router is malfunctioning but when I was able to connect my phone to my router I was sure that the router is not the culprit. Finally I rebooted and selected 5.15.5-arch1-1 & WiFi connection is instant. No issues at all.

Anyone who’s using the Hardened Kernel facing this issue ? Any workaround ?

Do you have the package r8168 installed? Try uninstalling it, and see whether that solves your issue (and if not, you can always install it back).

Seems like the hardened kernel is switching off your WiFi’s radio functionality. But why use the hardened kernel? yeah, it provides more security but it also disables a lot of stuff like some drivers for network interfaces.

Disabled Devices[edit]

Both kernels disable some drivers that are unlikely to be used to cut attack surface. The drivers disabled are as follows:

  • All staging drivers:
    • CONFIG_RTL8192U - RealTek RTL8192U Wireless LAN NIC driver
    • CONFIG_RTL8192E - RealTek RTL8192E Wireless LAN NIC driver
    • Intel Compute Stick, the CHIP and many other Intel Atom and ARM based devices
    • R8712U
    • D-Link DWA-130
    • CONFIG_R8188EU
    • TP-Link TL-WN725N
    • CONFIG_R8822BE - Realtek RTL8822BE 802.11ac
    • CONFIG_RTS5208 - Realtek PCI-E Card Reader RTS5208/5288 support
    • CONFIG_PI433 - Pi433 - a 433MHz radio module for Raspberry Pi
    • some data acquisition device such as CONFIG_COMEDI
  • All industrial I/O support (CONFIG_IIO) is disabled. This includes things like humidity sensors, chemical sensors, light sensors, accelerometers etc. that don’t really make sense on a usual desktop system.
  • All android support is disabled as these kernels aren’t meant to be used on any mobile devices.
  • Infiniband support.
  • SMC-R, “sockets over RDMA”, RDMA over Converged Ethernet (RoCE)

Source if needed.

For a normal user, Linux is secure enough unless you personally download a shady script and run it your self.

I had found that my ethernet interface was not enabled. I used the command ifconfig to verify that. A member of the #archlinux IRC channel told me to install the r8168 package from AUR. So had used the command yay -S r8168-dkms to install it.

I will uninstall that package & report back. But how can a driver which is meant for the ethernet cause problem for wifi ?

I am paranoid about security. As I said I have been using the Hardened Kernel for a long time now. Never faced any issues. This is the first problem.