I am working on a Dell Precision 5770 laptop which has Ubuntu Jammy 20.04.3. I was able to install the realtime kernel using ubuntu pro sudo pro enable realtime-kernel and it worked fine. However, upon rebooting, I lose my wifi adapter. I've checked and disabled secure boot, as one guide suggested to do so, but it was not helpful in getting it to work. I also have tried backporting the driver but it was unsuccessful. I can go into more detail about that if anyone is curious or can help me successfully do that, if that's the solution. Running the following commands shows me the following:
$ sudo lshw -C network
*-network
description: Network controller
product: Alder Lake-P PCH CNVi WiFi
vendor: Intel Corporation
physical id: 14.3
bus info: pci@0000:00:14.3
version: 01
width: 64 bits
clock: 33MHz
capabilities: bus_master cap_list
configuration: driver=iwlwifi latency=0
resources: iomemory:640-63f irq:16 memory:6491244000-6491247fff
Notably, this is missing a lot of the driver configuration information, the card serial, etc...
Here's some background for information
$ uname -a
Linux devrod-lap 5.15.0-1053-realtime #59-Ubuntu SMP PREEMPT_RT Fri Jan 12 20:29:00 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
$ lsmod | grep iwlwifi
iwlwifi 458752 1 iwlmvm
cfg80211 1011712 3 iwlmvm,iwlwifi,mac80211
$ lspci -k
0000:00:14.3 Network controller: Intel Corporation Alder Lake-P PCH CNVi WiFi (rev 01)
Subsystem: Intel Corporation Device 4090
Kernel driver in use: iwlwifi
Kernel modules: iwlwifi
$ rfkill list wlan
1: dell-wifi: Wireless LAN
Soft blocked: no
Hard blocked: no
$ iwconfig
lo no wireless extensions.
enx4cd717671816 no wireless extensions.
enx0015ff280501 no wireless extensions.
I've been pulling my hair out for 4 days trying every solution from every forum I could find, re-installing Ubuntu fixes the problem, so I assume it's a kernel issue. I eagerly await someone to guide me to success.
