When using the Atheros alx driver on Ubuntu 20.04 the Wake On Lan
feature is functional as long as a kernel 5.14 is used.
When switching to kernel 5.15 or newer the wol functionality is not
available anymore. Also using a newer Ubuntu version don't contain a
functional WOL with that ethernet interface.
This package adds the support for wol again as dkms package.
Since version 2.1 alx-wol is prepared for an easy adaption to other
distributions than Ubuntu.
First implemented is Debian.
Since version 2.0 of alx-wol this can not only be used to get alx driver with wake on lan working.
Now this can be used for any kernel module which shall be patched based on the original kernel sources. This system analyses the kernel which shal be installed, detects its version and the compiler used. The information about the kernel version is used to fetch the original sources from kernel.org. A config file tells the system which patch to use with which kernel version. The sources are patched. The system tries to find the optimal compiler for the module and builds with it. After that the initramf is updated to provide the new kernel module.
I was using an Ubuntu 20.04 on a home server containing the Atheros ethernet chip. I configured it for Wake On Lan a long time ago and with one ubuntu update the functionality was gone.
This was the change from kernel v5.14 to kernel v5.15.
That problem lead to the motivation to bring wol to life again. I checked the basis where wol was removed from the alx driver on kernel.org and created a patch to bring it in again.
With the next kernel update of Ubuntu I decided to get the compilation of the module done automatically. Here my journey into dkms started.
Now I released version 2.0 of alx-wol.
And to be honest: this is more than alx driver with wake on lan. This version is a framework for creating kernel modules based on original kernel sources. It automatically detects the kernel version and the compiler used for the kernel. Then it downloads the original kernel sources, applies configurable patches and builds. And last but not least it takes care to bring the module into the initramfs.
The alx-wol can be seen as one example for that mechanism. There are two more examples which can be found in 'other_examples'.
alx-wol has been tested on Ubuntu 22.04, 23.10 and 24.04. With regular kernel updates delieverd by Ubuntu the system works pretty nice. Also the kernels which can be downloaded from Mainline Kernel PPA work fine.
A short test has been executed on Debian 12 "bookworm".
In case of self compiled kernels one has to take care that the version strings follow one of the Ubuntu ways.
If you want to use newer mainline kernels you can download and install them. But you have to keep in mind that Ubuntu changes the environment for building these kernels. So it can happen that a precompiled kernel package leads to issues of alx-wol - which not neccesarily is based on the alx-wol mechanism.
That was the case with kernel versions 6.4.13 and newer. Here Ubuntu used a newer version of libc which wasn't compatible to the previous one. It was not possible to install these mainline kernel packages without additional big changes in the system. But as these packages can't be installed the dkms mechanisms of alx-wol are not triggered. It is NOT an issue of alx-wol.
With newer updates even Ubuntu 22.04 was switched to kernel 6.5. Here of course also alx-wol works fine.
With Ubuntu 23.10 Ubuntu introduced a change in update-initramfs. Getting that full functional was the kickoff for creating the generic kernel module patch system as it is here.
In general: Ubuntu 22.04, 22.10 and 23.04 are supported.
Kernel versions v5.15.50 and newer are supported.
But not all of the Ubuntu Mainline kernel packages are installable.
- clone the git repository
- cd into alx-wol
- execute as root ./install.sh
you may use sudo for the execution
The script will check if there's already an old version of this dkms.
If yes this can be deinstalled.
I didn't test the deinstallation very deeply. In the case that the
automatic deinstallation fails please use
sudo dkms remove alx-wol/<version_to_remove>
to get back to the original alx driver and then du the installation
again.
After that the new version is installed.
To do so the alx sources are fetched from kernel.org,
then the dkms mechanism is called to install the package.
As last action the script checks if the running kernel uses the original version of the alx driver. If yes it is replaced by the new compiled alx-wol module. The initrd is updated so that the wol feature is still available after the next reboot. If the kernel is changed to a different version the reboot should be done soon.
Calling the script remove.sh will remove all installed versions of
this package from dkms. Only the installed data will be removed, the
sources are not removed with the script.
Only versions which have been successfully installed are removed. In the case that there are artifacts from older versions these have to be removed manually.
To check if there are remaining artefacts call
dkms status
If there are packages with the matching name but not 'installed' at the end of the line there are some artifacts which should be removed. To do so use
sudo rm -rf /var/lib/dkms/<package_name>/<package_version>
If you also want to remove the original sources use
sudo rm -rf /usr/src/<package_name>-<package_version>
Caution! There is a minus between the package name and the version, NOT a slash as in the previous command!
This is a list of issues found in the Ubuntu world leading to large effort in alx-wol:
- different compilers used
there have been kernels which required a newer compiler than the one which was installed
Solution: since alx-wol version 2.0 the system tries to find the optimum compiler automatically - changes in dkms system
a newer dkms system doesn't detect differences in modules if the value of MODULE_VERSION doesn't differ
In case of alx it's even one step worse:
these sources don't contain that define
Solution: MODULE_VERSION is automatically patched and now contains a time stamp - changes in dkms system
when starting this project Ubuntus dkms system supported the feature REMAKE_INITRD
Since a newer version of Ubuntu the dkms reported this as depricated
Solution: own scripting around initramfs handling - different libc versions used
Starting with a kernel 6.4.something in the kernel ppa Ubuntu used a newer version of glibc to build the kernel
No solution for alx-wol - but the whole kernel can't be used on older Ubuntu systems
Solution is to use the regular updates for these systems, not the PPA kernels - changes in initramfs handling
since Ubuntu 23.04 Ubuntu changes to a new update-initramfs mechanism
With this mechanism no dkms build module is installed in the initramfs anymore
Solution: since version 2.0 there is an additional hook for mkinitramfs
This hook installs all dkms build modules into the initramfs
When installing the required kernel header the script extract-vmlinux
of the kernel sources is not installed. Because of that the script
extract_kversion_string.sh first checks if the script is available
and if not downloads and uses the one matching the currently running
kernel.
The new generic kernel module patch mechanism is explained here
Version 2.1
Introduction of mechanism to integrate other distributions than Ubuntu. First other distribution implemented: Debian.
Version 2.0
Introduction of generic kernel module patching mechanism
The patch mechanism supports falling back to defined patches
As long as these apply there should be no need to change anything in
alx-wol
First version which is able to handle update-initramfs on Ubuntu 23.10
Added documentation for the generic mechanism
Version 1.5
Introduced support for Kernel 6.5
Because of a change in update-initramfs this doesn't work on Ubuntu
23.10
Version 1.4.1
Workaround for missing dependency in 6.4.6 kernel package in ubuntu
Package expects to find gcc-13 but there is no dependency
Version 1.4
bugfix on installation of newer version of alx-wol
intruduction of support for kernel 6.4
Version 1.3
First full functional version
Supports Kernel 5.15 - 5.19, 6.0, 6.1, 6.2 and 6.3
Deinstallation of previous versions doesn't work correctly.
This package is provides AS IS.
Use it on your own risk.
The author doesn't take any responsibility for any kind of malfunction
or data loss on your system.