Documentation of kernel settings

[TobiPeterG]

Hey there,

First of all, thank you for your amazing work. :)

I'm building the bazzite kernel as personal project for openSUSE based distros (actually, I'm building a complete distro for handheld's based on openSUSE, a lot of packages are already in Tumbleweed, and you have solved a lot of issues I faced - so thank you very much for bazzite :) ). It works well so far, I use the patchwork kernel tree as is to built it, which works.
However, I would like to bring the kernel to the official openSUSE sources. On openSUSE's side, the kernel bringup process is a bit different. While there is an openSUSE kernel repo, the kernel for building is created by applying patches on top of the mainline kernel, so I would like/need to do this as well (openSUSE also doesn't need the redhat/fedora specific patches/files).

I already had a look at your documentation. There is a handheld patch list auto-generated, but that is a single file with all patches you apply on top of the Fedora ARK kernel. I'm curious: Do you have a list somewhere with the patches you apply and why? Do you keep track of the sources? Are there patches that are only available in your kernel tree and nowhere else? I haven't found it yet. If there isn't such a list available online, would it be possible to create one? I guess it might be interesting for other developers and some users to find out which patches you use from where and which hardware it enables with which kernel config parameter.

On a side note: Do you activate specific kernel config options (next to those enabling the handheld patches) and if yes, which and why? There is the https://github.com/bazzite-org/kernel-bazzite/blob/bazzite-6.17/kernel-x86_64-fedora.config , but comparing it to what openSUSE uses is a nightmare and it's not obvious which options differ because of openSUSE/fedora specific settings and which differ because e.g. experimental settings are enabled for performance improvements.

I am also curious how you bring up a new kernel version, I can see that 6.17 is still in beta for quite some time. But I guess that's another topic that is also hard to discuss via GitHub.

Anyway, have a nice evening :)

[antheas]

I'm curious: Do you have a list somewhere with the patches you apply and why?

The kernel tree is the only place the patches are stored. I do not maintain a separate folder of patch files. They are attributed properly and I aim to have them be self explanatory, although I realize that there should be more of a why and that is not ideal.

I just rebase them with git rebase -i --onto kernel-x.y.z-0 kernel-curr-0 to update the kernel tree. You coulddo e.g. git rebase -i --onto v6.17.5 kernel-6.17.5-0. Note that there are some new CI patches now, which will make this a bit hairy.

I am also curious how you bring up a new kernel version, I can see that 6.17 is still in beta for quite some time. But I guess that's another topic that is also hard to discuss via GitHub.

This repository is automatically generated as of 6.17 with the same tools Fedora uses, which were modified as well. An additional change is that we now bundle all OOT modules in the patchwork repo as submodules. This was a breaking change for Bazzite, as the kernel installation process was completely rewritten and there was a delay with adding the mok keys to the repo.

This made it so that 6.17 got delayed until Fedora 43, and we are about to release it. Usually, we aim to crossover at the .4 mark, and then unless a change affects desktops, stay on that version until we update the major version.

You will also notice there is an additional patch-3-akmods.patch that contains those OOT modules, after they are converted to patches.

Are there patches that are only available in your kernel tree and nowhere else?

I try to send the patches to the linux kernel, for the ones that will get accepted at least.

On a side note: Do you activate specific kernel config options (next to those enabling the handheld patches) and if yes, which and why?

Up to 6.16, this was the kernel-local file, but after switching to Fedora's build process, it is no longer in this repo. Now, it is CONFIG_LOCAL in the kernel tree.

Note that some of those config options, and specifically the ACPI_CALL patch do not meet secure boot requirements, in case you planned to sign the kernel. I am working on those requirements.

If you ask me about porting to openSUSE, I'd say reference redhat/scripts/genspec/genspec.sh which is used to generate the patch files instead of trying to remove the ark patches, and just live with patch-1-redhat.patch being there. It is not something major anyway, and will save you the work of rebasing. The kernel in this repository also builds by pulling the raw tar from kernel.org and applying those patches on top, anyhow.

[TobiPeterG]

@antheas thanks a lot for your quick reply and pointing me to the relevant parts! :)

Should I keep this issue open to track the "why" documentation or should I close it?

Have a nice evening :)

[antheas]

If you have further questions I guess you could ask

[TobiPeterG]

Hey, I just noticed that the 2-handheld.patch adds the oot drivers in /drivers/custom as 1600000. This means they are added as git submodule and the 3-akmods patch cannot be applied anymore. Is this something you would be willing to fix? If not, it's not a big deal, just wanted to let you know. :)

[antheas]

If you want to use the patches as is, use patch program and the third patch will apply cleanly.

See how they are applied in the kernel.spec file.

Otherwise, run git submodule update --init on the kernel tree, compile it directly, and skip the patches.