[OE-core] [PATCH 0/2] Support for VirtualBox guest additions

Wed Aug 5 22:02:12 UTC 2015

Thanks for the link. My new understanding is that kernel-dev package
should already have essentially the same functionality as the kernel-headers package,
which makes kernel-headers package redundant.
 I tried it, but it did not work.
To be specific, I expected to see the folder "/usr/lib/modules/3.19.5-yocto-standard/build"
however, it is missing . Looking at kernel.bbclass it seems it used to exist, but succumbed to
some bitrot.

Just to make sure  we are on the same page, this is what I would like to accomplish:
http://www.cyberciti.biz/tips/build-linux-kernel-module-against-installed-kernel-source-tree.html

Juro

> -----Original Message-----
> From: Bruce Ashfield [mailto:bruce.ashfield at gmail.com]
> Sent: Tuesday, August 4, 2015 7:49 PM
> To: Hatle, Mark G (Wind River)
> Cc: Bystricky, Juro; openembedded-core at lists.openembedded.org;
> jurobystricky at hotmail.com; Purdie, Richard
> Subject: Re: [OE-core] [PATCH 0/2] Support for VirtualBox guest additions
> 
> On Tue, Aug 4, 2015 at 11:43 PM, Bruce Ashfield <bruce.ashfield at gmail.com>
> wrote:
> > On Tue, Aug 4, 2015 at 2:32 PM, Mark Hatle <mark.hatle at windriver.com>
> wrote:
> >> On 8/4/15 12:25 PM, Bystricky, Juro wrote:
> >>> I agree, the name "kernel-headers" may not be the most fortunate,
> "linux-headers"
> >>> is probably more fitting.  The recipe installs the files in a
> >>> similar fashion that is done by
> >>>
> >>> apt-get install linux-headers-$(uname -r)
> >>>
> >>> Typical contents can be viewed for example here:
> >>> https://www.archlinux.org/packages/core/i686/linux-headers/
> >>>
> >>> These files are needed to allow building  of kernel drivers against
> >>> the running Linux kernel. In a way, it is a subset of kernel-devsrc,
> >>> but including  ".config" file used for the actual running kernel.
> >>
> >> Again this is part of the purpose of the existing kernel-devsrc
> >> package.  So what is missing preventing this from working.  It likely
> >> needs to be added to the kernel-devsrc package instead (or a sub
> >> package that is created by the kernel-devsrc recipe.)
> >
> > Peeking in on vacation.
> >
> > At a minimum, we need to figure out why the existing package wasn't
> > able to build the use case in question here .. I've built pretty much
> > everything against it at one point .. so I'd like to learn more.
> >
> > And yes, what we don't need is more sets of rules that copy and
> > package parts of the kernel build. We are already doing that in our
> > do_shared_workdir and that is pretty much the minimum to build against
> > the kernel. If that directory structure needs more for this purpose (or less),
> then update it.
> >
> > But we need to do all of this in the existing classes, to keep
> > everything in one place, not more recipes that are grabbing chunks of
> > the same source tree.
> 
> FYI: exiting thoughts are here:
> 
> https://bugzilla.yoctoproject.org/show_bug.cgi?id=7095
> 
> So as you can see, we aren't offended by a 'headers' package, but it has to
> make sense with the existing packages, and needs to be generating from our
> existing bits of the system.
> 
> Cheers,
> 
> Bruce
> 
> >
> > Bruce
> >
> >
> >>
> >>> Having these files installed, it is possible  to compile additional
> >>> kernel drivers that are not part of the kernel-devsrc .
> >>>  VirtualBox compiles some of their own drivers this way, others as well.
> >>> There are many other scenarios where you may want to add a new
> >>> kernel driver to an already installed Linux kernel.
> >>
> >> Yes, this was part of the design behind the kernel-devsrc, make sure
> >> the sources and components used to build the running kernel were made
> >> available to the target so that out-of-tree/external kernel modules
> >> could be built to match the running system -- as well as the ability
> >> to reconfigure and rebuild the kernel itself.
> >>
> >> Bruce is on vacation this week and may not be around to respond, but
> >> adding yet another package is not the right answer here.  Lets fix
> >> what may be broken in what we have.
> >>
> >> --Mark
> >>
> >>> Juro
> >>>
> >>>
> >>>
> >>>> -----Original Message-----
> >>>> From: Mark Hatle [mailto:mark.hatle at windriver.com]
> >>>> Sent: Tuesday, August 4, 2015 9:20 AM
> >>>> To: Bystricky, Juro; openembedded-core at lists.openembedded.org;
> >>>> jurobystricky at hotmail.com
> >>>> Cc: Purdie, Richard
> >>>> Subject: Re: [OE-core] [PATCH 0/2] Support for VirtualBox guest
> >>>> additions
> >>>>
> >>>> On 8/3/15 3:35 PM, Juro Bystricky wrote:
> >>>>> In order to support VirtualBox guest additions, kernel headers
> >>>>> need to be present in the VM. I am aware we already have two
> >>>>> packages/recipes that are somewhat similar (kernel-devsrc.bb,
> >>>>> linux-libc-headers), but none
> >>>> of them is suitable for this purpose.
> >>>>> Besides the kernel headers, some additional files (scripts,
> >>>>> Makefiles, .config, etc) are also required.
> >>>>
> >>>> linux-libc-headers is only for building applications.
> >>>> kernel-devsrc is for building modules on the target.
> >>>>
> >>>> What do these specific modules need that are not present in kernel-
> devsrc?
> >>>> (I really don't want 'yet another' confusing package added to the
> >>>> system.)
> >>>>
> >>>>> The new recipe "kernel-headers.bb" can in principle be used by
> >>>>> other
> >>>> images as well.
> >>>>> It is not limited to the Build Appliance and hence is not a part
> >>>>> of the Build Appliance recipe.
> >>>>
> >>>> I think kernel-headers is a bad name for a package.  It could be
> confusing.
> >>>>
> >>>> --Mark
> >>>>
> >>>>> Juro Bystricky (2):
> >>>>>   kernel-headers: linux kernel headers
> >>>>>   build-appliance-image: support for VirtualBox guest addtions
> >>>>>
> >>>>>  .../README_vbox_guest_additions.txt                | 78
> >>>> ++++++++++++++++++++++
> >>>>>  .../images/build-appliance-image_12.0.1.bb         |  4 +-
> >>>>>  meta/recipes-kernel/linux/kernel-headers.bb        | 66
> >>>> ++++++++++++++++++
> >>>>>  3 files changed, 147 insertions(+), 1 deletion(-)  create mode
> >>>>> 100644
> >>>>> meta/recipes-core/images/build-appliance-
> >>>> image/README_vbox_guest_addit
> >>>>> ions.txt  create mode 100644
> >>>>> meta/recipes-kernel/linux/kernel-headers.bb
> >>>>>
> >>>
> >>
> >> --
> >> _______________________________________________
> >> Openembedded-core mailing list
> >> Openembedded-core at lists.openembedded.org
> >> http://lists.openembedded.org/mailman/listinfo/openembedded-core
> >
> >
> >
> > --
> > "Thou shalt not follow the NULL pointer, for chaos and madness await
> > thee at its end"
> 
> 
> 
> --
> "Thou shalt not follow the NULL pointer, for chaos and madness await thee
> at its end"