network not working updating to kernel 5.8 ubuntu 20.04

After updating the kernel to 5.8.0-36-generic and rebooting I noticed the network wasn't working.

Using the previous working kernel I've found that the problem was related to drivers not present because my interfaces were UNCLAIMED using lshw -c network.

I've found other posts suggesting to install the linux-generic-hwe in my case linux-generic-hwe-20.04.

After installing it the interfaces where recognized.

I can't quite get what happened, and probably don't quite know where to look for information about this, the previous kernel worked fine. I don't understand if the driver was removed between kernel releases or something else..

The output of sudo lshw -c network with the network working is pasted here:

  *-network
       description: Wireless interface
       product: Dual Band Wireless-AC 3168NGW [Stone Peak]
       vendor: Intel Corporation
       physical id: 0
       bus info: pci@0000:03:00.0
       logical name: wlp3s0
       version: 10
       serial: 60:f6:77:65:e5:69
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=iwlwifi driverversion=5.8.0-36-generic firmware=29.1654887522.0 3168-29.ucode ip=192.168.1.9 latency=0 link=yes multicast=yes wireless=IEEE 802.11
       resources: irq:128 memory:df100000-df101fff

So it looks is something related to iwlwifi.

Anybody can give any info regarding this, the update process finished with no errors, so I guess it's something else.

Solution 1:

Also lost network connection after updating from kernel 5.4.0 to kernel 5.8.0-41.

Looking at the output of

dpkg -l | grep linux-

I figured out that in my case the previous kernels had linux-modules-extra- packages installed, but linux-modules-extra-5.8.0-41-generic was missing. After booting a 5.4.0 kernel (with working network connection) I could fix the problem by

sudo apt install linux-modules-extra-5.8.0-41-generic

Solution 2:

I was also facing a similar problem with the wireless network and the touchpad not working after upgrading to 5.8 kernel.

I found this question.

After running

dpkg -l | grep linux-

I found that the modules for linux-modules-5.8.0-38-generic wasn't installed but the previous kernel's modules were.

So if you can connect to a wired network, doing

sudo apt-get install linux-modules-5.8.0-38-generic linux-headers-5.8.0-38-generic

should install them. That seemed to work for me.

If you are like me, who cant connect to wired network, try switching the kernel in the grub ' Advanced options for Ubuntu ' to a previous working version of the kernel, and try installing the above.

Solution 3:

I had the same issue when I updated to 5.8.0-63 kernel. My wifi, sound and graphics were messed up.

Following the answers by Jörg and Harish above, I booted into an older kernel with working internet from the Ubuntu advanced options in the boot menu and ran the following command

dpkg -l | grep linux-

I installed the 2 packages: headers and extra, that were missing for the newest kernel.

sudo apt install linux-modules-extra-5.8.0-63-generic linux-headers-5.8.0-63-generic

After reboot, everything works perfectly again.