support current mainline Linux kernel features (eg bcachefs)

[froh]

Is your feature request related to a problem? Please describe.

When I want to try recent kernel features (e.g. bcachefs), I have to go back to "some real VM" because WSL needs additional patches.

Currently the wsl patches are out-of-tree. They are non-trivial to integrate into a current kernel release and it's non-trivial to build the wsl2 base image (based off such a recent kernel).

Describe the solution you'd like

• provide a mainline-release+wsl patchset kernel, with wsl2 ready kconfig, ready to build & ship.
• provide a binary ready to use
  • e.g. enable wsl vendors like ubuntu and arch and openSUSE to pick that up and offer it as an alternative kernel
  • or if you want to control it, offer it as a wsl2-current-kernel stream for "wsl.exe --update"
  • note that mature Linux distros have a fallback mechanism, a wsl.exe --update solution should have the same

just to spell it out: "additionally" mainlining the patches will help for two reasons:

• technically, the majority of forward porting is done by those changing APIs you consume.
• politically, mainlining enforces the statement: "we, MS, are dead serious about wsl."

Describe alternatives you've considered

I don't see any.

Additional context

none.

[froh]

any news on mainlining the wsl patchset and on providing a close-to-mainline wsl/wslg kernel?