[yocto] Build external module against Yocto kernel

[Patrick Turley]

On Jan 16, 2013, at 11:11 AM, Darren Hart <dvhart at linux.intel.com> wrote:
> On 01/15/2013 10:38 AM, Bruce Ashfield wrote:
>> 
>> I finally found the entries that I was recalling earlier. They are:
>> 
>> https://bugzilla.yoctoproject.org/show_bug.cgi?id=241
>> https://bugzilla.yoctoproject.org/show_bug.cgi?id=1614
>> https://bugzilla.yoctoproject.org/show_bug.cgi?id=2968
>> 
>> 1614 and 2968 are the most interesting for what you are asking.
>> 
>> As you can see the net result of those bugs is that you can get the
>> right parts of the kernel tree in SDK packages, since they include
>> dev packages, and with what is currently in kernel-dev .. it should
>> be enough to build against in the SDK (perhaps with just the LDFLAGS
>> tweaks mentioned in the other thread). The sources should be part
>> of the sysroot, and hence available when that is packaged for use
>> outside of bitbake/yocto.
>> 
>> If you aren't seeing kernel-dev in the SDK image, it might be that
>> TOOLCHAIN_TARGET_TASK doesn't have kernel-dev by default, or something
>> else is different in the SDK that is being generated in your testing.
>> 
>> I'm only speculating about what might be missing, since I'm not 100%
>> familiar with the SDK, but perhaps Jessica or others can chime in if
>> I've led you astray :)
>> 
> 
> Thanks for keeping this going Bruce. Yes, kernel-dev is the package for
> the target. The only trick here is that we currently purge the host
> binaries which means that you need to build scripts on the target prior
> to building the module.
> 
> I think this might be missing from the new kernel manual as it isn't a
> particularly common use-case, and is rather orthogonal to the way the
> tooling has been designed (not to say it can't be done).
> 
> Patrick, please keep us posted if this continues to not work for you. I
> will open a bug to include a section about this in the kernel
> development manual.

I got sick and was also diverted to other things, so I apologize for not responding sooner. I am very appreciative of every CPU cycle you have all spent considering this issue -- I wouldn't want you to imagine otherwise.

I will gladly have a look at those issues and absorb the information you've offered. I will also let you all know if it works for me.