[OE-core] [PATCH v9] kernel: Add support for multiple kernel packages

[Otavio Salvador]

On Mon, Nov 13, 2017 at 5:16 PM, Haris Okanovic <haris.okanovic at ni.com> wrote:
> On 11/10/2017 04:00 PM, Wold, Saul wrote:
>>
>> On Fri, 2017-11-10 at 15:51 -0600, Haris Okanovic wrote:
>>>
>>> No problem! Thanks for all the good feedback. I think we shook out
>>> most
>>> of the gremlins in the last few months.
>>>
>> Thanks again for your patience !
>>
>>> Let me know if you need help with boot loader integration.
>>>
>> Funny you should mention that, there is another bug recently opened
>> about supporting multiple kernels for at least grub* and systemd-boot.
>>
>> I have some ideas about using the existing bbclasses and extending the
>> LABELS variable automagically.  We also have some plans for make the
>> bootfs be created in a more generic install fashion, rather then the
>> additional do_deploy() function, this is an early WIP.
>>
>> If you have any ideas or work already, we would be happy to use it.
>>
>
> Unfortunately, we don't have any good selection mechanism just yet. Our main
> use case is to aid in debugging driver issues, mostly aimed at kernel
> developers. We provide an image + modules in our feed that's compiled with
> debug options, and require the user to select a preferred boot kernel via
> symlink on the file system.
>
> I envisioned using update-alternatives in the future to facilitate
> selection. The call from postinst would give preference to OE's preferred
> provider while a call from users could override that, if desired.
>
> I'm not familiar with the <bootloader>.bbclass-es and the LABELS variable.
> We use a static boot loader config on our systems. How would this work if a
> kernel is installed from feed -- I.e. after image build? Is there a
> mechanism to rebuild the boot loader config dynamically?

I belive this needs to be done on target, as a post-installation hook.

Debian and other generic distributions handle this using this
strategy. Also it is tied to the bootloader. So we'll need two
versions (grub and u-boot/syslinux).

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750