[OE-core] [PATCH 2/2] kernel: Add optional patch_xenomai task

[Marek Vasut]

On 01/07/2018 08:00 PM, Bruce Ashfield wrote:
> On Sun, Jan 7, 2018 at 1:57 PM, Marek Vasut <marex at denx.de> wrote:
>> On 01/07/2018 07:55 PM, Bruce Ashfield wrote:
>>> On Sun, Jan 7, 2018 at 1:49 PM, Marek Vasut <marex at denx.de> wrote:
>>>> On 01/07/2018 06:55 PM, Bruce Ashfield wrote:
>>>>> On Sun, Jan 7, 2018 at 12:53 PM, Marek Vasut <marex at denx.de> wrote:
>>>>>> On 01/07/2018 05:42 PM, Bruce Ashfield wrote:
>>>>>>> On Sun, Jan 7, 2018 at 11:38 AM, Marek Vasut <marex at denx.de> wrote:
>>>>>>>> On 01/07/2018 05:37 PM, Bruce Ashfield wrote:
>>>>>>>>> On Sun, Jan 7, 2018 at 11:19 AM, Marek Vasut <marex at denx.de> wrote:
>>>>>>>>>> Add additional task, do_patch_xenomai, inserted between do_patch and
>>>>>>>>>> do_configure tasks. This task applies the cobalt patch to the kernel
>>>>>>>>>> sources for a specific machine. This is disabled by default, so use
>>>>>>>>>> PACKAGECONFIG[xenomai] of the kernel package to enable the patching.
>>>>>>>>>>
>>>>>>>>>> You will also need a kernel recipe for a kernel version with ipipe
>>>>>>>>>> patch applied.
>>>>>>>>>
>>>>>>>>> This doesn't make any sense to me.
>>>>>>>>>
>>>>>>>>> Why on earth would this be in kernel.bbclass ? and part of a xenomai
>>>>>>>>> recipe ?
>>>>>>>> Do you have a better suggestion how to make this easily available for
>>>>>>>> every kernel recipe ?
>>>>>>>
>>>>>>> There's no need to make it available for every kernel recipe. If someone
>>>>>>> wants to build xenomai, they need to have a specific kernel recipe and
>>>>>>> configuration to make it work. By providing that patch and allowing it to
>>>>>>> be applied to any kernel doesn't mean it will actually work .. so you aren't
>>>>>>> doing anyone any favours.
>>>>>>>
>>>>>>> The same thing could be said for the -rt patch, aufs, etc, any patch could
>>>>>>> be made available for any kernel, but they aren't, since they will either fail
>>>>>>> to patch, or won't work at runtime.
>>>>>> We actually have a -rt patch available in the kernel recipes, so why not
>>>>>> xenomai patch ?
>>>>>
>>>>> As a separate recipe, not as something in a common bbclass, which implies
>>>>> that it applies and works everywhere.
>>>>>
>>>>> Anyone that is trying to apply -rt against a generic kernel .. is very mistaken.
>>>>
>>>> So I should pull this into linux-*-xenomai , just like the rt patch does?
>>>
>>> Yep.
>>>
>>> But how it is maintained is a RP question, oe-core has a set of reference kernel
>>> versions, and those reference kernels have a similar set of functionality across
>>> architectures, are actively maintained and all get the same fixes at
>>> the same time.
>>>
>>> (and I just realized that RP isn't copied on this thread anymore, so I'm adding
>>> him).
>>>
>>> If we introduce something like this, I'd argue that it needs to follow the same
>>> kernel versions to be consistent with the other oe-core references.
>>>
>>> That is a question for the steering committee and the architecture mailing list.
>>>
>>> So while that happens, why not just put this in a meta-xenomai for the time
>>> being and once all the details have been hammered out, it could merge.
>> That's fine by me, although the main feedback I'm currently interested
>> in is whether this has any chance of getting included in oe-core and if
>> there are some other big issues with this .
> 
> There has been interest in this in the past, which is why I've gone down the
> route of getting things up and running myself.
> 
> The real feedback and feasibility would be in those other forums, but if done
> right, I don't see why not myself.

OK fine, so let's see.

-- 
Best regards,
Marek Vasut