Kernel 5.10 on Ubuntu 20.04 (or later) (for T2 Apple hardware)

[Krzysztof Kozlowski]

On 26/05/2021 14:44, Will McGinnis wrote:
> Hi Krzysztof, Thanks so much for the response.
> 
> The Linux on the T2 project issmall (but dedicated!) so out of ease of
> maintenance, across all distros, only a few kernel versions have been
> chosen to test the patches for the T2 Apple hardware.
> From the T2 Linux main page: "versions 5.7.19 and 5.11.x, which reached
> end of life as well as the stable 5.10.x, which will be supported by the
> Linux maintainers until December 2026.

There is only one proper solution for adding support for new hardware or
new features - upstream your code. All other choices are unfortunately
suboptimal. Of course nothing stops you from forking Linux and keeping
your patches out of tree but in the long term this will be additional
work (which you mentioned - maintenance).

Once your code lands upstream, everyone - including all distros - can
make use of it. You will also receive review and fixes coming from
community.

> The purpose/need/goal for using 5.10 would be for my own use but also
> for other users of the T2 Linux patches with Ubuntu, anyone that wants to.
> 
> I definitely see the value in building on the work of the existing
> Ubuntu kernels whenever possible rather than getting plain vanilla
> kernel sources, so if there's a sanctioned way to get 5.10.x I would
> prefer that (for my own use and to recommend to others, once I get it
> working and test it for a bit)

The recommended way is to upstream, do not build on top of v5.10
(neither vanilla nor Ubuntu) and rather do not maintain it separately.

I will be also happy to help in upstream process, if you ever are
interested.

> My interest in the OEM kernel is only because it says the specific
> 5.10.x kernel version that I'm looking for. If the regular linux image
> generic was 5.10.x then I would be fine using that. But I am reaching
> out since it's not clear what the best way is to get both 5.10.x and the
> Ubuntu kernel team patches together.

I understand. I guess now you can start with the v5.10 OEM, but as
Kai-Heng wrote - later it might change.

Best regards,
Krzysztof