What you need to know
- Microsoft has released a new kernel for WSL2 that jumps all the way from the 5.15 LTS it has been using for some time to the much newer 6.6 LTS.
- It hasn’t yet been rolled into WSL2, but the source is up on GitHub for folks to build if they wish.
- Configuration changes include loadable modules for x86 and ARM64.
Anyone using the Windows Subsystem for Linux (WSL) on a regular basis will no doubt have noticed that it’s been stuck on the 5.15 kernel in WSL2 for what feels like an eternity. That’s about to change, though, as Microsoft has released its first 6.6 kernel (via Phoronix), albeit only through GitHub right now.
That means that it hasn’t yet been rolled into the latest version of WSL, but if you’re keen to be on the cutting edge, you can go ahead and grab it, then build it yourself. It is a fairly involved, and tedious process, mind, and if you’ve never done it before you’re probably best off waiting. I lost half an hour this morning trying to build it, only for it to error out.
For WSL2, Microsoft utilizes an LTS kernel over a rolling release, which is why it’s been back on such an old kernel for so long. But the time has finally come to move to a newer LTS, and the 6.x releases add a lot into the mix. Specifically, this release uses the stable kernel 6.6.36.
The full changelog looks a little like this:
- First WSL2 kernel release updated to v6.6 from v5.15
- Release rolling-lts/wsl/6.6.36.3
- Update to stable kernel version v6.6.36
- New x86 and ARM64 configs including loadable modules
- dxgkrnl: Do not print error messages when virtual GPU is not present
- Fewer out of tree patches. Sets of patches now included from upstream:
- page reporting commits (feature/page-reporting/5.15)
- vpci commits (feature/vpci/5.15)
- memory reclaim commits (feature/memory-reclaim/5.15)
- vsock commits (fix/vsock/5.15)
As Phoronix also points out, the jump to 6.6 also makes for less out-of-tree patches to be maintained by Microsoft. The Linux kernel has had a significant number of features added upstream in the years since the 5.15 kernel Microsoft has been using, so such patches simply won’t be required.
There’s no word on when the new kernel will be rolling out as the new default in WSL2, but I can’t imagine it’ll be too long a wait now that it’s off and rolling.
