How to properly build/use 6.6 kernel with WSL and NixOS?

[chrisportela]

I have built a 6.6 kernel using instructions from Microsoft and put it at my WSL kernel.

Everything starts. However there are a lot of errors. I imagine it has to do with the step where it says to run sudo make modules_install headers_install and presumably that sets up the example ubuntu WSL to be able to use the new kernel.

I have found some random attempts (unmaintained) to build custom kernels for use with WSL. I really want to build a kernel with proper zram support because I am running some builds which use up so much memory that they die even with 60GB of memory allocated to WSL.

What is the proper way to build and setup a custom kernel for WSL in NixOS? Is that something this project is planning to support at all?

If there isn't a straight forward answer, where should I start looking? I understand that we can't enable the normal NixOS kernel builds because WSL provides the kernel, but if I built my own nixos.wsl tarball I don't logically understand how to get that to do what I want.

[573]

Did you see https://lgug2z.com/articles/yubikey-passthrough-on-wsl2-with-full-fido2-support/#building-and-loading-a-custom-wsl2-linux-kernel ?

And #110 (comment) ?

[chrisportela]

Finally got around to doing this. I built my own kernel off of the example linked. The kernel does not have errors when loading. There are some issues with zram that I don't understand yet (need to debug, read dmesg, etc.), but so far so good.

To answer one of my questions: when you do the build there is also <result>/lib/modules/... folder which you can copy into the right place and that helps with autocomplete in modinfo as well as provide the modules that aren't built in to the kernel.

Still not sure how to put those in the right place via just building nixos itself, but it's a step in the right direction.