Thunderbird – Fix Parsing Error After Upgrade to Ubuntu 20.10

The problem I found out is generated every time dmesg.log is updated. Solution is to reset wireless connection. It is generally not only Thunderbird but sending out network connection problem.

UPDATE : Ubuntu 21.04 current ISO image was tested, it includes kernel 5.11.0-11 and the installation proceeded normally.

The 5.11 Ubuntu distribution kernels are causing the same instability problems with Gnome, KDE, XFCE (at least) like the home-compiled 5.11 kernels, if you are facing the same problems stay with kernels before 5.11 .

UPDATE 2 : Kernel was upgraded to 5.11.0-22, everything works fine.

TIP : You can download and test the Latest Development ISO by synchronizing with the following command.

zsync http://cdimage.ubuntu.com/daily-live/current/impish-desktop-amd64.iso.zsync

The first time you run the command the ISO will be downloaded, any other time you run the same command in the ISO's directory the system will check whether there are any changes and it will update the ISO if necessary.

Recommended Solution : Install a kernel version that works, from your distribution's repository

Note : If you want to perform a fresh installation from an image that crashes the graphical installation environment due to this i915 problem, select (Safe Graphics) in the ISO's boot menu and after the installation perform the necessary steps.

For example a Focal Fossa user will download and install the following packages from

https://packages.ubuntu.com/focal/kernel/

1. linux-image-(kernel_version)-generic
2. linux-modules-(kernel_version)-generic
3. linux-modules-extra-(kernel_version)-generic

Install with command,

sudo apt install <package>

Reboot.

The system will automatically boot with the new kernel if you haven't installed any newer kernel, in any other case select the kernel from the GRUB menu.

Advanced approach

The solution for kernels before 5.11 is here Red Hat Bugzilla – Bug 1843274

The GUI system can become usable if you boot with your old kernel 5.4.0 . The terminal is still usable with 5.8.0 kernel, try CTRL+ALT+F3.

The solution is to patch the i915 module. Download the patch from here

To understand the patch have a look at Intel's Manual page 50, it has to do with the command MEDIA_VFE_STATE which has to be provided with the right number of threads according to the model of the GPU.

First method: Patch and recompile a new kernel

Quick guide

0. The basic dependencies to build the kernel are sudo apt install libncurses-dev flex bison openssl libssl-dev dkms libelf-dev libudev-dev libpci-dev libiberty-dev autoconf
1. Download the kernel source of your choice from www.kernel.org and extract it.
2. Go inside the kernel source directory.
3. Clean the kernel with sudo make mrproper in the kernel's directory.
4. Download the patch into the kernel's source code parent directory.
5. Apply the patch with patch -p1 < ../drm-i915-gt-Limit-VFE-threads-based-on-GT.patch
6. Configure the kernel or run sudo make localmodconfig to finish quickly, hold the Enter key until all the questions are answered
7. Compile the kernel with sudo make -j (# of CPU threads) bindeb-pkg
8. Install the linux-image and the linux-headers deb packages produced in the parent directory of the kernel source directory
9. Reboot and if necessary choose the new kernel from the GRUB menu

Optimize the above procedure according to your preferences, your hardware etc

Second method: Patch and recompile the module only

It is also possible to rebuild the patched module for an already installed kernel so as to be able to use the official distribution kernels or any other precompiled kernels.

The official i915 compilation guide from Intel is here, if you download it as a PDF go to page 41.

You can follow the steps exactly as they are presented but notice the following.

1. If you are going to recompile the module for another kernel version than the one you are running then you have to replace $(uname -r) with the version you are targeting, for example 5.8.0-29-generic .

2. If you use the /tmp/kernel directory as in the guide then this directory will be lost after a reboot.

3. After step 5 you have to patch the kernel with patch -p1 < ../drm-i915-gt-Limit-VFE-threads-based-on-GT.patch assuming the patch is located into the kernel's source code parent directory

4. Step 9 can be skipped.

5. After step 12 you may get an error concerning the cryptographic verification of the module, there is no problem, the module has been installed in /lib/modules/5.8.0-29-generic/extradrivers and the system knows that it is there and should be loaded through step 13.

6. Step 14 should be performed stating the target kernel version, for 5.8.0-29-generic alter the commands like this sudo depmod -v 5.8.0-29-generic and sudo update-initramfs -k 5.8.0-29-generic -u .

After a reboot your system will be usable again.

This procedure should be performed for any new kernel until the problem is solved by Ubuntu.