Building Out-of-Tree Modules on the BBB Target

Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

Hello to the YOCTO community,

I am using (to build the target for Beagle Bone Black) the following script:
https://github.com/ZoranStojsavljevic/bbb-yocto
https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh

The latest kernel I am using from the following repo:
https://github.com/jumpnow/meta-bbb

Is kernel 5.0.14 .

Here is the snippet of the boot traces:
Starting kernel ...

[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
[    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
[    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
instruction cache
[    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
[    0.000000] Memory policy: Data cache writeback
[    0.000000] cma: Reserved 16 MiB at 0x9f000000
[    0.000000] CPU: All CPU(s) started in SVC mode.
[    0.000000] AM335X ES2.1 (sgx neon)
[    0.000000] random: get_random_bytes called from
start_kernel+0xa4/0x460 with crng_init=0
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 130048
[    0.000000] Kernel command line: console=ttyO0,115200n8
root=/dev/ram0 ip=dhcp

According to the documentation, the following:
2.10.1. Building Out-of-Tree Modules on the Target
https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html

I tried to find /usr/src/kernels/5.0.14... Directory, since I see
from the build that kernel-dev and kernel-devsrc are included:
[user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
core-image-kernel-dev                                 :1.0-r0
kernel-devsrc                                         :1.0-r0
kernel-selftest                                       :1.0-r0

THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
directory at all!?

Two questions here?
[1] Do you have any advice on this problem (what I am missing here)?
[2] Alternative to [1]: how I can use cross compiler from
.../build/tmp to build Out-of-Tree Module for the BBB target on the
host?

Thank you,
Zoran
_______

Re: Building Out-of-Tree Modules on the BBB Target

[Bruce Ashfield]

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On Sun, May 12, 2019 at 6:54 AM Zoran Stojsavljevic <
zoran.stojsavljevic@gmail.com> wrote:

> Hello to the YOCTO community,
>
> I am using (to build the target for Beagle Bone Black) the following
> script:
> https://github.com/ZoranStojsavljevic/bbb-yocto
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>
> The latest kernel I am using from the following repo:
> https://github.com/jumpnow/meta-bbb
>
> Is kernel 5.0.14 .
>
> Here is the snippet of the boot traces:
> Starting kernel ...
>
> [    0.000000] Booting Linux on physical CPU 0x0
> [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7),
> cr=10c5387d
> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
> instruction cache
> [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
> [    0.000000] Memory policy: Data cache writeback
> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> [    0.000000] CPU: All CPU(s) started in SVC mode.
> [    0.000000] AM335X ES2.1 (sgx neon)
> [    0.000000] random: get_random_bytes called from
> start_kernel+0xa4/0x460 with crng_init=0
> [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages:
> 130048
> [    0.000000] Kernel command line: console=ttyO0,115200n8
> root=/dev/ram0 ip=dhcp
>
> According to the documentation, the following:
> 2.10.1. Building Out-of-Tree Modules on the Target
> https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>
> I tried to find /usr/src/kernels/5.0.14... Directory, since I see
> from the build that kernel-dev and kernel-devsrc are included:
> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> core-image-kernel-dev                                 :1.0-r0
> kernel-devsrc                                         :1.0-r0
> kernel-selftest                                       :1.0-r0
>
> THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
> directory at all!?
>

devsrc puts the source in /usr/src/kernel/ and also makes a symlink to
/lib/modules/<version>/source

Was /usr/src/kernels/ a typo ? If you aren't seeing the source in either of
the two locations I mention above, then we do have a bug.
You also have to recreate the scripts/tools in that source directory before
building, via a 'make scripts prepare' in the /usr/src/kernel directory.


>
> Two questions here?
> [1] Do you have any advice on this problem (what I am missing here)?
> [2] Alternative to [1]: how I can use cross compiler from
> .../build/tmp to build Out-of-Tree Module for the BBB target on the
> host?
>

Are you talking about doing this by hand ? in the SDK or with a recipe ? If
it is via SDK or recipe, then everything is setup to work if you follow the
hello-world module example in meta-skeleton. If you are trying to invoke
things using another build system, there are more hoops to jump through.

The yocto QA steps do perform out of tree kernel module builds, so it
should be working.

I checked and the yocto mega manual should be up to date in this area, if
it isn't, raising a bug in the tracker would point us to where it has gone
stale (since it does look like you've been using it, so there very well
could be an issue).

Bruce



>
> Thank you,
> Zoran
> _______
> --
> _______________________________________________
> yocto mailing list
> yocto@yoctoproject.org
> https://lists.yoctoproject.org/listinfo/yocto
>


-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

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Re: Building Out-of-Tree Modules on the BBB Target

[Chris Simmonds]

Hi Zoran,

There are two ways to do this

1. Build using a bb recipe.
Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
You just need to add meta-skeleton to your bblaysers.conf and then
  bitbake hello-mod


2. Build from the SDK:
First, add the kernel source to the SDK by adding this to conf/local/conf
  TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"

Then build the SDK
  bitbake -c populate_sdk [your image recipe]

Once the SDK is installed, generate the kernel headers:
  sudo -i
  . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
  cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
  cd /usr/src/kernel
  make oldconfig scripts
  exit

Finally, build your module using a Makefile like this

  obj-m := hello-mod.o
  all:
        make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)


HTH,
Chris

On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
> Hello to the YOCTO community,
> 
> I am using (to build the target for Beagle Bone Black) the following script:
> https://github.com/ZoranStojsavljevic/bbb-yocto
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
> 
> The latest kernel I am using from the following repo:
> https://github.com/jumpnow/meta-bbb
> 
> Is kernel 5.0.14 .
> 
> Here is the snippet of the boot traces:
> Starting kernel ...
> 
> [    0.000000] Booting Linux on physical CPU 0x0
> [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
> instruction cache
> [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
> [    0.000000] Memory policy: Data cache writeback
> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> [    0.000000] CPU: All CPU(s) started in SVC mode.
> [    0.000000] AM335X ES2.1 (sgx neon)
> [    0.000000] random: get_random_bytes called from
> start_kernel+0xa4/0x460 with crng_init=0
> [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 130048
> [    0.000000] Kernel command line: console=ttyO0,115200n8
> root=/dev/ram0 ip=dhcp
> 
> According to the documentation, the following:
> 2.10.1. Building Out-of-Tree Modules on the Target
> https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
> 
> I tried to find /usr/src/kernels/5.0.14... Directory, since I see
> from the build that kernel-dev and kernel-devsrc are included:
> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> core-image-kernel-dev                                 :1.0-r0
> kernel-devsrc                                         :1.0-r0
> kernel-selftest                                       :1.0-r0
> 
> THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
> directory at all!?
> 
> Two questions here?
> [1] Do you have any advice on this problem (what I am missing here)?
> [2] Alternative to [1]: how I can use cross compiler from
> .../build/tmp to build Out-of-Tree Module for the BBB target on the
> host?
> 
> Thank you,
> Zoran
> _______
> 


-- 
Chris Simmonds, trainer and consultant at 2net
http://www.2net.co.uk
Author of "Mastering Embedded Linux Programming"

Re: Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

Hello Bruce, Chris,

Thank you both for the replies.

Usually, the kernel header files/kernel source code for the used
kernels are put under: /usr/src/kernels/`uname -r`/

But this, my best guess, is an implementation detail (probably each
distro has its own rule/merit).

Since YOCTO is just one of many areas I work on... I expected the
routine. But, hey... ;-)
_______

In my opinion it would be nice to have this all by default implemented
outside of SDK. Included by default in rootfs. But this is only my
desperate wish (I am, after all, old, very lazy person)!

I figured it out in BBB related Embedded Debian (there are few tricks
to be done) today (aside that my HOST EFI grub2 failed very badly
(some bad sectors on my SSD), so I had some emergency to figure out
how to recover it - all done).

So, in embedded Debian I am able to build it on BBB target out of the
tree (few steps must be done to accomplish that).

I'll try what you both suggested to me for YOCTO (I still need some time):

> 1. Build using a bb recipe.
> Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
> You just need to add meta-skeleton to your bblaysers.conf and then
>  bitbake hello-mod

Please, stay tuned!

Thank you once again,
Zoran
_______

On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk> wrote:
>
> Hi Zoran,
>
> There are two ways to do this
>
> 1. Build using a bb recipe.
> Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
> You just need to add meta-skeleton to your bblaysers.conf and then
>   bitbake hello-mod
>
>
> 2. Build from the SDK:
> First, add the kernel source to the SDK by adding this to conf/local/conf
>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>
> Then build the SDK
>   bitbake -c populate_sdk [your image recipe]
>
> Once the SDK is installed, generate the kernel headers:
>   sudo -i
>   . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>   cd /usr/src/kernel
>   make oldconfig scripts
>   exit
>
> Finally, build your module using a Makefile like this
>
>   obj-m := hello-mod.o
>   all:
>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>
>
> HTH,
> Chris
>
> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
> > Hello to the YOCTO community,
> >
> > I am using (to build the target for Beagle Bone Black) the following script:
> > https://github.com/ZoranStojsavljevic/bbb-yocto
> > https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
> >
> > The latest kernel I am using from the following repo:
> > https://github.com/jumpnow/meta-bbb
> >
> > Is kernel 5.0.14 .
> >
> > Here is the snippet of the boot traces:
> > Starting kernel ...
> >
> > [    0.000000] Booting Linux on physical CPU 0x0
> > [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
> > version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> > [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
> > [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
> > instruction cache
> > [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
> > [    0.000000] Memory policy: Data cache writeback
> > [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> > [    0.000000] CPU: All CPU(s) started in SVC mode.
> > [    0.000000] AM335X ES2.1 (sgx neon)
> > [    0.000000] random: get_random_bytes called from
> > start_kernel+0xa4/0x460 with crng_init=0
> > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 130048
> > [    0.000000] Kernel command line: console=ttyO0,115200n8
> > root=/dev/ram0 ip=dhcp
> >
> > According to the documentation, the following:
> > 2.10.1. Building Out-of-Tree Modules on the Target
> > https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
> >
> > I tried to find /usr/src/kernels/5.0.14... Directory, since I see
> > from the build that kernel-dev and kernel-devsrc are included:
> > [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> > core-image-kernel-dev                                 :1.0-r0
> > kernel-devsrc                                         :1.0-r0
> > kernel-selftest                                       :1.0-r0
> >
> > THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
> > directory at all!?
> >
> > Two questions here?
> > [1] Do you have any advice on this problem (what I am missing here)?
> > [2] Alternative to [1]: how I can use cross compiler from
> > .../build/tmp to build Out-of-Tree Module for the BBB target on the
> > host?
> >
> > Thank you,
> > Zoran
> > _______
> >
>
>
> --
> Chris Simmonds, trainer and consultant at 2net
> http://www.2net.co.uk
> Author of "Mastering Embedded Linux Programming"

Re: Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

Hello Chris, Bruce,

I have some additional data to share with you both, since I have tried
something. And here is my take on the things!

> 1. Build using a bb recipe.
> Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
> You just need to add meta-skeleton to your bblayers.conf and then
>  bitbake hello-mod

I looked into this example, and, yes, it is classic kernel module
definition out of the tree. With some outdated data, all cool, the
YOCTO designer should take care himself to fix these data, if using
this stuff.

But this is NOT mandatory, since I can add out of the tree module NOT
actually using built-in module. I just use .../tmp/deploy/images/bbb/*
generated stuff, since I have automated scripts which are bringing all
these on my BBB target. Then I tftp my source code module to the
target.

> 2. Build from the SDK:
> First, add the kernel source to the SDK by adding this to conf/local.conf
>  TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"

YES, this is THE command which should generate
/usr/src/kernel(s)/`uname -r` or similar... But adding it to
local.conf and after deleting kernel, then regenerating bitbake -k
core-image-minimal does not bring this path into the rootfs image!?

I did it actually using meta-bbb, and using poky referent distro as
two additional layers to the more complex bbb image!
https://github.com/jumpnow/meta-bbb.git

The (KAS - you can figure out out of it local.conf) script I am using
to build such a BBB image is here:
https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml

I did not try it with BBB reference poky only! Maybe I should try it
as only referent poky? What do you think?

Does in this case is SDK build really mandatory??? Should NOT be!

> Once the SDK is installed, generate the kernel headers:
>  sudo -i
>  . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>  cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>  cd /usr/src/kernel
>  make oldconfig scripts
>  exit

This is in nutshell the same what I did (a bit different) for Embedded
Debian. This is already on the target BBB, NOT while building YOCTO
BBB image!

> Finally, build your module using a Makefile like this
>  obj-m := hello-mod.o
>  all:
>        make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)

As said before: bringing my own module into the target BBB (I have my
own examples, and I build them on the target with the almost the same
Makefiles)

Zoran
_______

On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk> wrote:
>
> Hi Zoran,
>
> There are two ways to do this
>
> 1. Build using a bb recipe.
> Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
> You just need to add meta-skeleton to your bblaysers.conf and then
>   bitbake hello-mod
>
>
> 2. Build from the SDK:
> First, add the kernel source to the SDK by adding this to conf/local/conf
>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>
> Then build the SDK
>   bitbake -c populate_sdk [your image recipe]
>
> Once the SDK is installed, generate the kernel headers:
>   sudo -i
>   . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>   cd /usr/src/kernel
>   make oldconfig scripts
>   exit
>
> Finally, build your module using a Makefile like this
>
>   obj-m := hello-mod.o
>   all:
>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>
>
> HTH,
> Chris
>
> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
> > Hello to the YOCTO community,
> >
> > I am using (to build the target for Beagle Bone Black) the following script:
> > https://github.com/ZoranStojsavljevic/bbb-yocto
> > https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
> >
> > The latest kernel I am using from the following repo:
> > https://github.com/jumpnow/meta-bbb
> >
> > Is kernel 5.0.14 .
> >
> > Here is the snippet of the boot traces:
> > Starting kernel ...
> >
> > [    0.000000] Booting Linux on physical CPU 0x0
> > [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
> > version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> > [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
> > [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
> > instruction cache
> > [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
> > [    0.000000] Memory policy: Data cache writeback
> > [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> > [    0.000000] CPU: All CPU(s) started in SVC mode.
> > [    0.000000] AM335X ES2.1 (sgx neon)
> > [    0.000000] random: get_random_bytes called from
> > start_kernel+0xa4/0x460 with crng_init=0
> > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 130048
> > [    0.000000] Kernel command line: console=ttyO0,115200n8
> > root=/dev/ram0 ip=dhcp
> >
> > According to the documentation, the following:
> > 2.10.1. Building Out-of-Tree Modules on the Target
> > https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
> >
> > I tried to find /usr/src/kernels/5.0.14... Directory, since I see
> > from the build that kernel-dev and kernel-devsrc are included:
> > [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> > core-image-kernel-dev                                 :1.0-r0
> > kernel-devsrc                                         :1.0-r0
> > kernel-selftest                                       :1.0-r0
> >
> > THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
> > directory at all!?
> >
> > Two questions here?
> > [1] Do you have any advice on this problem (what I am missing here)?
> > [2] Alternative to [1]: how I can use cross compiler from
> > .../build/tmp to build Out-of-Tree Module for the BBB target on the
> > host?
> >
> > Thank you,
> > Zoran
> > _______
> >
>
>
> --
> Chris Simmonds, trainer and consultant at 2net
> http://www.2net.co.uk
> Author of "Mastering Embedded Linux Programming"

Re: Building Out-of-Tree Modules on the BBB Target

[Bruce Ashfield]

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On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <
zoran.stojsavljevic@gmail.com> wrote:

> Hello Chris, Bruce,
>
> I have some additional data to share with you both, since I have tried
> something. And here is my take on the things!
>
> > 1. Build using a bb recipe.
> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
> > You just need to add meta-skeleton to your bblayers.conf and then
> >  bitbake hello-mod
>
> I looked into this example, and, yes, it is classic kernel module
> definition out of the tree. With some outdated data, all cool, the
> YOCTO designer should take care himself to fix these data, if using
> this stuff.
>
> But this is NOT mandatory, since I can add out of the tree module NOT
> actually using built-in module. I just use .../tmp/deploy/images/bbb/*
> generated stuff, since I have automated scripts which are bringing all
> these on my BBB target. Then I tftp my source code module to the
> target.
>
> > 2. Build from the SDK:
> > First, add the kernel source to the SDK by adding this to conf/local.conf
> >  TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>
> YES, this is THE command which should generate
> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
> local.conf and after deleting kernel, then regenerating bitbake -k
> core-image-minimal does not bring this path into the rootfs image!?
>

That's correct. That command only adds the kernel source and build
infrastructure to the SDK, not to your target image. You'd still need to
arrange to have the kernel-devsrc package installed on the target image if
you want it on the board's rootfs. How you arrange to have the package
installed to the image varies with the image (since they all don't have the
same image install variables, etc).



>
> I did it actually using meta-bbb, and using poky referent distro as
> two additional layers to the more complex bbb image!
> https://github.com/jumpnow/meta-bbb.git
>
> The (KAS - you can figure out out of it local.conf) script I am using
> to build such a BBB image is here:
>
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>
> I did not try it with BBB reference poky only! Maybe I should try it
> as only referent poky? What do you think?
>
> Does in this case is SDK build really mandatory??? Should NOT be!
>
>
You only do the SDK steps if you want to support building out of tree
modules in an SDK install. So it is not mandatory for on target module
builds.

Bruce



> > Once the SDK is installed, generate the kernel headers:
> >  sudo -i
> >  . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >  cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >  cd /usr/src/kernel
> >  make oldconfig scripts
> >  exit
>
> This is in nutshell the same what I did (a bit different) for Embedded
> Debian. This is already on the target BBB, NOT while building YOCTO
> BBB image!
>
> > Finally, build your module using a Makefile like this
> >  obj-m := hello-mod.o
> >  all:
> >        make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>
> As said before: bringing my own module into the target BBB (I have my
> own examples, and I build them on the target with the almost the same
> Makefiles)
>
> Zoran
> _______
>
> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk> wrote:
> >
> > Hi Zoran,
> >
> > There are two ways to do this
> >
> > 1. Build using a bb recipe.
> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
> > You just need to add meta-skeleton to your bblaysers.conf and then
> >   bitbake hello-mod
> >
> >
> > 2. Build from the SDK:
> > First, add the kernel source to the SDK by adding this to conf/local/conf
> >   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >
> > Then build the SDK
> >   bitbake -c populate_sdk [your image recipe]
> >
> > Once the SDK is installed, generate the kernel headers:
> >   sudo -i
> >   . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >   cd /usr/src/kernel
> >   make oldconfig scripts
> >   exit
> >
> > Finally, build your module using a Makefile like this
> >
> >   obj-m := hello-mod.o
> >   all:
> >         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
> >
> >
> > HTH,
> > Chris
> >
> > On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
> > > Hello to the YOCTO community,
> > >
> > > I am using (to build the target for Beagle Bone Black) the following
> script:
> > > https://github.com/ZoranStojsavljevic/bbb-yocto
> > >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
> > >
> > > The latest kernel I am using from the following repo:
> > > https://github.com/jumpnow/meta-bbb
> > >
> > > Is kernel 5.0.14 .
> > >
> > > Here is the snippet of the boot traces:
> > > Starting kernel ...
> > >
> > > [    0.000000] Booting Linux on physical CPU 0x0
> > > [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
> > > version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> > > [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7),
> cr=10c5387d
> > > [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
> > > instruction cache
> > > [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
> > > [    0.000000] Memory policy: Data cache writeback
> > > [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> > > [    0.000000] CPU: All CPU(s) started in SVC mode.
> > > [    0.000000] AM335X ES2.1 (sgx neon)
> > > [    0.000000] random: get_random_bytes called from
> > > start_kernel+0xa4/0x460 with crng_init=0
> > > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages:
> 130048
> > > [    0.000000] Kernel command line: console=ttyO0,115200n8
> > > root=/dev/ram0 ip=dhcp
> > >
> > > According to the documentation, the following:
> > > 2.10.1. Building Out-of-Tree Modules on the Target
> > > https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
> > >
> > > I tried to find /usr/src/kernels/5.0.14... Directory, since I see
> > > from the build that kernel-dev and kernel-devsrc are included:
> > > [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> > > core-image-kernel-dev                                 :1.0-r0
> > > kernel-devsrc                                         :1.0-r0
> > > kernel-selftest                                       :1.0-r0
> > >
> > > THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
> > > directory at all!?
> > >
> > > Two questions here?
> > > [1] Do you have any advice on this problem (what I am missing here)?
> > > [2] Alternative to [1]: how I can use cross compiler from
> > > .../build/tmp to build Out-of-Tree Module for the BBB target on the
> > > host?
> > >
> > > Thank you,
> > > Zoran
> > > _______
> > >
> >
> >
> > --
> > Chris Simmonds, trainer and consultant at 2net
> > http://www.2net.co.uk
> > Author of "Mastering Embedded Linux Programming"
>


-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

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Re: Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

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> That's correct. That command only adds the kernel source and
> build infrastructure to the SDK, not to your target image. *You'd still*
*> need to arrange to have the kernel-devsrc package installed on the*
*> target image if you want it on the board's rootfs.* How you arrange
> to have the package installed to the image varies with the image
> (since they all don't have the same image install variables, etc).

And here is a $1,000,000 USD question? How to do it on Poky (as
example of what you have stated in RED)? ;-)

In other words: how to arrange it on Poky (as a Referent example)?

Thank you,
Zoran
_______


On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <bruce.ashfield@gmail.com>
wrote:

>
>
> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
>
>> Hello Chris, Bruce,
>>
>> I have some additional data to share with you both, since I have tried
>> something. And here is my take on the things!
>>
>> > 1. Build using a bb recipe.
>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>> > You just need to add meta-skeleton to your bblayers.conf and then
>> >  bitbake hello-mod
>>
>> I looked into this example, and, yes, it is classic kernel module
>> definition out of the tree. With some outdated data, all cool, the
>> YOCTO designer should take care himself to fix these data, if using
>> this stuff.
>>
>> But this is NOT mandatory, since I can add out of the tree module NOT
>> actually using built-in module. I just use .../tmp/deploy/images/bbb/*
>> generated stuff, since I have automated scripts which are bringing all
>> these on my BBB target. Then I tftp my source code module to the
>> target.
>>
>> > 2. Build from the SDK:
>> > First, add the kernel source to the SDK by adding this to
>> conf/local.conf
>> >  TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>
>> YES, this is THE command which should generate
>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
>> local.conf and after deleting kernel, then regenerating bitbake -k
>> core-image-minimal does not bring this path into the rootfs image!?
>>
>
> That's correct. That command only adds the kernel source and build
> infrastructure to the SDK, not to your target image. You'd still need to
> arrange to have the kernel-devsrc package installed on the target image if
> you want it on the board's rootfs. How you arrange to have the package
> installed to the image varies with the image (since they all don't have the
> same image install variables, etc).
>
>
>
>>
>> I did it actually using meta-bbb, and using poky referent distro as
>> two additional layers to the more complex bbb image!
>> https://github.com/jumpnow/meta-bbb.git
>>
>> The (KAS - you can figure out out of it local.conf) script I am using
>> to build such a BBB image is here:
>>
>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>>
>> I did not try it with BBB reference poky only! Maybe I should try it
>> as only referent poky? What do you think?
>>
>> Does in this case is SDK build really mandatory??? Should NOT be!
>>
>>
> You only do the SDK steps if you want to support building out of tree
> modules in an SDK install. So it is not mandatory for on target module
> builds.
>
> Bruce
>
>
>
>> > Once the SDK is installed, generate the kernel headers:
>> >  sudo -i
>> >  . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>> >  cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>> >  cd /usr/src/kernel
>> >  make oldconfig scripts
>> >  exit
>>
>> This is in nutshell the same what I did (a bit different) for Embedded
>> Debian. This is already on the target BBB, NOT while building YOCTO
>> BBB image!
>>
>> > Finally, build your module using a Makefile like this
>> >  obj-m := hello-mod.o
>> >  all:
>> >        make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>>
>> As said before: bringing my own module into the target BBB (I have my
>> own examples, and I build them on the target with the almost the same
>> Makefiles)
>>
>> Zoran
>> _______
>>
>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk> wrote:
>> >
>> > Hi Zoran,
>> >
>> > There are two ways to do this
>> >
>> > 1. Build using a bb recipe.
>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>> > You just need to add meta-skeleton to your bblaysers.conf and then
>> >   bitbake hello-mod
>> >
>> >
>> > 2. Build from the SDK:
>> > First, add the kernel source to the SDK by adding this to
>> conf/local/conf
>> >   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>> >
>> > Then build the SDK
>> >   bitbake -c populate_sdk [your image recipe]
>> >
>> > Once the SDK is installed, generate the kernel headers:
>> >   sudo -i
>> >   . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>> >   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>> >   cd /usr/src/kernel
>> >   make oldconfig scripts
>> >   exit
>> >
>> > Finally, build your module using a Makefile like this
>> >
>> >   obj-m := hello-mod.o
>> >   all:
>> >         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>> >
>> >
>> > HTH,
>> > Chris
>> >
>> > On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>> > > Hello to the YOCTO community,
>> > >
>> > > I am using (to build the target for Beagle Bone Black) the following
>> script:
>> > > https://github.com/ZoranStojsavljevic/bbb-yocto
>> > >
>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>> > >
>> > > The latest kernel I am using from the following repo:
>> > > https://github.com/jumpnow/meta-bbb
>> > >
>> > > Is kernel 5.0.14 .
>> > >
>> > > Here is the snippet of the boot traces:
>> > > Starting kernel ...
>> > >
>> > > [    0.000000] Booting Linux on physical CPU 0x0
>> > > [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
>> > > version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>> > > [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7),
>> cr=10c5387d
>> > > [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
>> > > instruction cache
>> > > [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
>> > > [    0.000000] Memory policy: Data cache writeback
>> > > [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>> > > [    0.000000] CPU: All CPU(s) started in SVC mode.
>> > > [    0.000000] AM335X ES2.1 (sgx neon)
>> > > [    0.000000] random: get_random_bytes called from
>> > > start_kernel+0xa4/0x460 with crng_init=0
>> > > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages:
>> 130048
>> > > [    0.000000] Kernel command line: console=ttyO0,115200n8
>> > > root=/dev/ram0 ip=dhcp
>> > >
>> > > According to the documentation, the following:
>> > > 2.10.1. Building Out-of-Tree Modules on the Target
>> > > https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>> > >
>> > > I tried to find /usr/src/kernels/5.0.14... Directory, since I see
>> > > from the build that kernel-dev and kernel-devsrc are included:
>> > > [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>> > > core-image-kernel-dev                                 :1.0-r0
>> > > kernel-devsrc                                         :1.0-r0
>> > > kernel-selftest                                       :1.0-r0
>> > >
>> > > THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
>> > > directory at all!?
>> > >
>> > > Two questions here?
>> > > [1] Do you have any advice on this problem (what I am missing here)?
>> > > [2] Alternative to [1]: how I can use cross compiler from
>> > > .../build/tmp to build Out-of-Tree Module for the BBB target on the
>> > > host?
>> > >
>> > > Thank you,
>> > > Zoran
>> > > _______
>> > >
>> >
>> >
>> > --
>> > Chris Simmonds, trainer and consultant at 2net
>> > http://www.2net.co.uk
>> > Author of "Mastering Embedded Linux Programming"
>>
>
>
> --
> - Thou shalt not follow the NULL pointer, for chaos and madness await thee
> at its end
> - "Use the force Harry" - Gandalf, Star Trek II
>
>

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Re: Building Out-of-Tree Modules on the BBB Target

[Bruce Ashfield]

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On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic <
zoran.stojsavljevic@gmail.com> wrote:

> > That's correct. That command only adds the kernel source and
> > build infrastructure to the SDK, not to your target image. *You'd still*
> *> need to arrange to have the kernel-devsrc package installed on the*
> *> target image if you want it on the board's rootfs.* How you arrange
> > to have the package installed to the image varies with the image
> > (since they all don't have the same image install variables, etc).
>
> And here is a $1,000,000 USD question? How to do it on Poky (as
> example of what you have stated in RED)? ;-)
>
> In other words: how to arrange it on Poky (as a Referent example)?
>

The core-image-kernel-dev image is how I do all my on target testing when I
introduce a new reference kernel for a release. And IIRC the autobuilders
are using a sato based image (Richard could confirm more easily that I
could what image type the autobuilders are using for hello-world on target
module tests).

Bruce



>
> Thank you,
> Zoran
> _______
>
>
> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <bruce.ashfield@gmail.com>
> wrote:
>
>>
>>
>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <
>> zoran.stojsavljevic@gmail.com> wrote:
>>
>>> Hello Chris, Bruce,
>>>
>>> I have some additional data to share with you both, since I have tried
>>> something. And here is my take on the things!
>>>
>>> > 1. Build using a bb recipe.
>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>>> > You just need to add meta-skeleton to your bblayers.conf and then
>>> >  bitbake hello-mod
>>>
>>> I looked into this example, and, yes, it is classic kernel module
>>> definition out of the tree. With some outdated data, all cool, the
>>> YOCTO designer should take care himself to fix these data, if using
>>> this stuff.
>>>
>>> But this is NOT mandatory, since I can add out of the tree module NOT
>>> actually using built-in module. I just use .../tmp/deploy/images/bbb/*
>>> generated stuff, since I have automated scripts which are bringing all
>>> these on my BBB target. Then I tftp my source code module to the
>>> target.
>>>
>>> > 2. Build from the SDK:
>>> > First, add the kernel source to the SDK by adding this to
>>> conf/local.conf
>>> >  TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>>
>>> YES, this is THE command which should generate
>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
>>> local.conf and after deleting kernel, then regenerating bitbake -k
>>> core-image-minimal does not bring this path into the rootfs image!?
>>>
>>
>> That's correct. That command only adds the kernel source and build
>> infrastructure to the SDK, not to your target image. You'd still need to
>> arrange to have the kernel-devsrc package installed on the target image if
>> you want it on the board's rootfs. How you arrange to have the package
>> installed to the image varies with the image (since they all don't have the
>> same image install variables, etc).
>>
>>
>>
>>>
>>> I did it actually using meta-bbb, and using poky referent distro as
>>> two additional layers to the more complex bbb image!
>>> https://github.com/jumpnow/meta-bbb.git
>>>
>>> The (KAS - you can figure out out of it local.conf) script I am using
>>> to build such a BBB image is here:
>>>
>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>>>
>>> I did not try it with BBB reference poky only! Maybe I should try it
>>> as only referent poky? What do you think?
>>>
>>> Does in this case is SDK build really mandatory??? Should NOT be!
>>>
>>>
>> You only do the SDK steps if you want to support building out of tree
>> modules in an SDK install. So it is not mandatory for on target module
>> builds.
>>
>> Bruce
>>
>>
>>
>>> > Once the SDK is installed, generate the kernel headers:
>>> >  sudo -i
>>> >  . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>> >  cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>> >  cd /usr/src/kernel
>>> >  make oldconfig scripts
>>> >  exit
>>>
>>> This is in nutshell the same what I did (a bit different) for Embedded
>>> Debian. This is already on the target BBB, NOT while building YOCTO
>>> BBB image!
>>>
>>> > Finally, build your module using a Makefile like this
>>> >  obj-m := hello-mod.o
>>> >  all:
>>> >        make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>>>
>>> As said before: bringing my own module into the target BBB (I have my
>>> own examples, and I build them on the target with the almost the same
>>> Makefiles)
>>>
>>> Zoran
>>> _______
>>>
>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk> wrote:
>>> >
>>> > Hi Zoran,
>>> >
>>> > There are two ways to do this
>>> >
>>> > 1. Build using a bb recipe.
>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>>> > You just need to add meta-skeleton to your bblaysers.conf and then
>>> >   bitbake hello-mod
>>> >
>>> >
>>> > 2. Build from the SDK:
>>> > First, add the kernel source to the SDK by adding this to
>>> conf/local/conf
>>> >   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>> >
>>> > Then build the SDK
>>> >   bitbake -c populate_sdk [your image recipe]
>>> >
>>> > Once the SDK is installed, generate the kernel headers:
>>> >   sudo -i
>>> >   .
>>> /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>> >   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>> >   cd /usr/src/kernel
>>> >   make oldconfig scripts
>>> >   exit
>>> >
>>> > Finally, build your module using a Makefile like this
>>> >
>>> >   obj-m := hello-mod.o
>>> >   all:
>>> >         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>>> >
>>> >
>>> > HTH,
>>> > Chris
>>> >
>>> > On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>>> > > Hello to the YOCTO community,
>>> > >
>>> > > I am using (to build the target for Beagle Bone Black) the following
>>> script:
>>> > > https://github.com/ZoranStojsavljevic/bbb-yocto
>>> > >
>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>>> > >
>>> > > The latest kernel I am using from the following repo:
>>> > > https://github.com/jumpnow/meta-bbb
>>> > >
>>> > > Is kernel 5.0.14 .
>>> > >
>>> > > Here is the snippet of the boot traces:
>>> > > Starting kernel ...
>>> > >
>>> > > [    0.000000] Booting Linux on physical CPU 0x0
>>> > > [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
>>> > > version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>>> > > [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7),
>>> cr=10c5387d
>>> > > [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
>>> > > instruction cache
>>> > > [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
>>> > > [    0.000000] Memory policy: Data cache writeback
>>> > > [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>>> > > [    0.000000] CPU: All CPU(s) started in SVC mode.
>>> > > [    0.000000] AM335X ES2.1 (sgx neon)
>>> > > [    0.000000] random: get_random_bytes called from
>>> > > start_kernel+0xa4/0x460 with crng_init=0
>>> > > [    0.000000] Built 1 zonelists, mobility grouping on.  Total
>>> pages: 130048
>>> > > [    0.000000] Kernel command line: console=ttyO0,115200n8
>>> > > root=/dev/ram0 ip=dhcp
>>> > >
>>> > > According to the documentation, the following:
>>> > > 2.10.1. Building Out-of-Tree Modules on the Target
>>> > > https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>>> > >
>>> > > I tried to find /usr/src/kernels/5.0.14... Directory, since I see
>>> > > from the build that kernel-dev and kernel-devsrc are included:
>>> > > [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>>> > > core-image-kernel-dev                                 :1.0-r0
>>> > > kernel-devsrc                                         :1.0-r0
>>> > > kernel-selftest                                       :1.0-r0
>>> > >
>>> > > THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
>>> > > directory at all!?
>>> > >
>>> > > Two questions here?
>>> > > [1] Do you have any advice on this problem (what I am missing here)?
>>> > > [2] Alternative to [1]: how I can use cross compiler from
>>> > > .../build/tmp to build Out-of-Tree Module for the BBB target on the
>>> > > host?
>>> > >
>>> > > Thank you,
>>> > > Zoran
>>> > > _______
>>> > >
>>> >
>>> >
>>> > --
>>> > Chris Simmonds, trainer and consultant at 2net
>>> > http://www.2net.co.uk
>>> > Author of "Mastering Embedded Linux Programming"
>>>
>>
>>
>> --
>> - Thou shalt not follow the NULL pointer, for chaos and madness await
>> thee at its end
>> - "Use the force Harry" - Gandalf, Star Trek II
>>
>>

-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

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Re: Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

> The core-image-kernel-dev image is how I do all my on target
> testing when I introduce a new reference kernel for a release.

Maybe you are correct. Maybe I should use/add in my local.conf the following:

KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
packagegroup-core-buildessential kernel-devsrc"
KERNEL_DEV_MODULE ?= "kernel-modules"
CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
                             ${KERNEL_DEV_TOOLS} \
                             systemtap \
                            "
I need to try these... Maybe this addendum will solve the $1 mio USD problem?!

> And IIRC the autobuilders are using a sato based image (Richard
> could confirm more easily that I could what image type the
> autobuilders are using for hello-world on target module tests).

I am just advertising something more simple. To have mandatory
/lib/modules/`uname -r` directory. And introduce few more packages, as
Fedora distro, for example, has: kernel-headers (assuming YOCTO
rootfs, the following will be installed: /usr/src/kernel/`uname
-r`/<header file directory structures>. This also makes addition of
/lib/modules/`uname -r`/build file (which is soft link to
usr/src/kernel/`uname -r`).

Or kernel-devel package. Then, the whole current kernel source code
will be introduced, and also support for it.

SDK building with such a support is good/cool. But sometimes, before
introducing SDK, some tests should be done on target. NO need to
optionally include built-in layer hello-world driver example. Since I
(or you name the person) have own test drivers, which will be imported
out of tree, externally, to the target test bed!

Just thinking loud...

Zoran
_______

On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>
>
>
> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>>
>> > That's correct. That command only adds the kernel source and
>> > build infrastructure to the SDK, not to your target image. You'd still
>> > need to arrange to have the kernel-devsrc package installed on the
>> > target image if you want it on the board's rootfs. How you arrange
>> > to have the package installed to the image varies with the image
>> > (since they all don't have the same image install variables, etc).
>>
>> And here is a $1,000,000 USD question? How to do it on Poky (as
>> example of what you have stated in RED)? ;-)
>>
>> In other words: how to arrange it on Poky (as a Referent example)?
>
>
> The core-image-kernel-dev image is how I do all my on target testing when I introduce a new reference kernel for a release. And IIRC the autobuilders are using a sato based image (Richard could confirm more easily that I could what image type the autobuilders are using for hello-world on target module tests).
>
> Bruce
>
>
>>
>>
>> Thank you,
>> Zoran
>> _______
>>
>>
>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>>>
>>>
>>>
>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>>>>
>>>> Hello Chris, Bruce,
>>>>
>>>> I have some additional data to share with you both, since I have tried
>>>> something. And here is my take on the things!
>>>>
>>>> > 1. Build using a bb recipe.
>>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>>>> > You just need to add meta-skeleton to your bblayers.conf and then
>>>> >  bitbake hello-mod
>>>>
>>>> I looked into this example, and, yes, it is classic kernel module
>>>> definition out of the tree. With some outdated data, all cool, the
>>>> YOCTO designer should take care himself to fix these data, if using
>>>> this stuff.
>>>>
>>>> But this is NOT mandatory, since I can add out of the tree module NOT
>>>> actually using built-in module. I just use .../tmp/deploy/images/bbb/*
>>>> generated stuff, since I have automated scripts which are bringing all
>>>> these on my BBB target. Then I tftp my source code module to the
>>>> target.
>>>>
>>>> > 2. Build from the SDK:
>>>> > First, add the kernel source to the SDK by adding this to conf/local.conf
>>>> >  TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>>>
>>>> YES, this is THE command which should generate
>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
>>>> local.conf and after deleting kernel, then regenerating bitbake -k
>>>> core-image-minimal does not bring this path into the rootfs image!?
>>>
>>>
>>> That's correct. That command only adds the kernel source and build infrastructure to the SDK, not to your target image. You'd still need to arrange to have the kernel-devsrc package installed on the target image if you want it on the board's rootfs. How you arrange to have the package installed to the image varies with the image (since they all don't have the same image install variables, etc).
>>>
>>>
>>>>
>>>>
>>>> I did it actually using meta-bbb, and using poky referent distro as
>>>> two additional layers to the more complex bbb image!
>>>> https://github.com/jumpnow/meta-bbb.git
>>>>
>>>> The (KAS - you can figure out out of it local.conf) script I am using
>>>> to build such a BBB image is here:
>>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>>>>
>>>> I did not try it with BBB reference poky only! Maybe I should try it
>>>> as only referent poky? What do you think?
>>>>
>>>> Does in this case is SDK build really mandatory??? Should NOT be!
>>>>
>>>
>>> You only do the SDK steps if you want to support building out of tree modules in an SDK install. So it is not mandatory for on target module builds.
>>>
>>> Bruce
>>>
>>>
>>>>
>>>> > Once the SDK is installed, generate the kernel headers:
>>>> >  sudo -i
>>>> >  . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>>> >  cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>>> >  cd /usr/src/kernel
>>>> >  make oldconfig scripts
>>>> >  exit
>>>>
>>>> This is in nutshell the same what I did (a bit different) for Embedded
>>>> Debian. This is already on the target BBB, NOT while building YOCTO
>>>> BBB image!
>>>>
>>>> > Finally, build your module using a Makefile like this
>>>> >  obj-m := hello-mod.o
>>>> >  all:
>>>> >        make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>>>>
>>>> As said before: bringing my own module into the target BBB (I have my
>>>> own examples, and I build them on the target with the almost the same
>>>> Makefiles)
>>>>
>>>> Zoran
>>>> _______
>>>>
>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk> wrote:
>>>> >
>>>> > Hi Zoran,
>>>> >
>>>> > There are two ways to do this
>>>> >
>>>> > 1. Build using a bb recipe.
>>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>>>> > You just need to add meta-skeleton to your bblaysers.conf and then
>>>> >   bitbake hello-mod
>>>> >
>>>> >
>>>> > 2. Build from the SDK:
>>>> > First, add the kernel source to the SDK by adding this to conf/local/conf
>>>> >   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>>> >
>>>> > Then build the SDK
>>>> >   bitbake -c populate_sdk [your image recipe]
>>>> >
>>>> > Once the SDK is installed, generate the kernel headers:
>>>> >   sudo -i
>>>> >   . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>>> >   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>>> >   cd /usr/src/kernel
>>>> >   make oldconfig scripts
>>>> >   exit
>>>> >
>>>> > Finally, build your module using a Makefile like this
>>>> >
>>>> >   obj-m := hello-mod.o
>>>> >   all:
>>>> >         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>>>> >
>>>> >
>>>> > HTH,
>>>> > Chris
>>>> >
>>>> > On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>>>> > > Hello to the YOCTO community,
>>>> > >
>>>> > > I am using (to build the target for Beagle Bone Black) the following script:
>>>> > > https://github.com/ZoranStojsavljevic/bbb-yocto
>>>> > > https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>>>> > >
>>>> > > The latest kernel I am using from the following repo:
>>>> > > https://github.com/jumpnow/meta-bbb
>>>> > >
>>>> > > Is kernel 5.0.14 .
>>>> > >
>>>> > > Here is the snippet of the boot traces:
>>>> > > Starting kernel ...
>>>> > >
>>>> > > [    0.000000] Booting Linux on physical CPU 0x0
>>>> > > [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
>>>> > > version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>>>> > > [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
>>>> > > [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
>>>> > > instruction cache
>>>> > > [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
>>>> > > [    0.000000] Memory policy: Data cache writeback
>>>> > > [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>>>> > > [    0.000000] CPU: All CPU(s) started in SVC mode.
>>>> > > [    0.000000] AM335X ES2.1 (sgx neon)
>>>> > > [    0.000000] random: get_random_bytes called from
>>>> > > start_kernel+0xa4/0x460 with crng_init=0
>>>> > > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 130048
>>>> > > [    0.000000] Kernel command line: console=ttyO0,115200n8
>>>> > > root=/dev/ram0 ip=dhcp
>>>> > >
>>>> > > According to the documentation, the following:
>>>> > > 2.10.1. Building Out-of-Tree Modules on the Target
>>>> > > https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>>>> > >
>>>> > > I tried to find /usr/src/kernels/5.0.14... Directory, since I see
>>>> > > from the build that kernel-dev and kernel-devsrc are included:
>>>> > > [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>>>> > > core-image-kernel-dev                                 :1.0-r0
>>>> > > kernel-devsrc                                         :1.0-r0
>>>> > > kernel-selftest                                       :1.0-r0
>>>> > >
>>>> > > THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
>>>> > > directory at all!?
>>>> > >
>>>> > > Two questions here?
>>>> > > [1] Do you have any advice on this problem (what I am missing here)?
>>>> > > [2] Alternative to [1]: how I can use cross compiler from
>>>> > > .../build/tmp to build Out-of-Tree Module for the BBB target on the
>>>> > > host?
>>>> > >
>>>> > > Thank you,
>>>> > > Zoran
>>>> > > _______
>>>> > >
>>>> >
>>>> >
>>>> > --
>>>> > Chris Simmonds, trainer and consultant at 2net
>>>> > http://www.2net.co.uk
>>>> > Author of "Mastering Embedded Linux Programming"
>>>
>>>
>>>
>>> --
>>> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>>> - "Use the force Harry" - Gandalf, Star Trek II
>>>
>
>
> --
> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
> - "Use the force Harry" - Gandalf, Star Trek II
>

Re: Building Out-of-Tree Modules on the BBB Target

[Bruce Ashfield]

[-- Attachment #1: Type: text/plain, Size: 12902 bytes --]

On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic <
zoran.stojsavljevic@gmail.com> wrote:

> > The core-image-kernel-dev image is how I do all my on target
> > testing when I introduce a new reference kernel for a release.
>
> Maybe you are correct. Maybe I should use/add in my local.conf the
> following:
>
> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
> packagegroup-core-buildessential kernel-devsrc"
> KERNEL_DEV_MODULE ?= "kernel-modules"
> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>                              ${KERNEL_DEV_TOOLS} \
>                              systemtap \
>                             "
> I need to try these... Maybe this addendum will solve the $1 mio USD
> problem?!
>
> > And IIRC the autobuilders are using a sato based image (Richard
> > could confirm more easily that I could what image type the
> > autobuilders are using for hello-world on target module tests).
>
> I am just advertising something more simple. To have mandatory
> /lib/modules/`uname -r` directory. And introduce few more packages, as
> Fedora distro, for example, has: kernel-headers (assuming YOCTO
> rootfs, the following will be installed: /usr/src/kernel/`uname
> -r`/<header file directory structures>. This also makes addition of
> /lib/modules/`uname -r`/build file (which is soft link to
> usr/src/kernel/`uname -r`).


These have all been discussed off an on over the past 5 years. I can't get
at bugzilla right now, but all the details are logged in cases. A survey of
all the distros, their kernel package, etc, were all looked at. We had to
balance the traditional packaging with some new concepts and landed with
what we have now.



> Or kernel-devel package. Then, the whole current kernel source code
> will be introduced, and also support for it.
>

There's a case for this one as well, I'll probably have it done for the
fall release. But our devsrc used to pretty much be the full source it has
now been pruned down to something more manageable.  There are definitely
some cases for having the full source on the target again, and it will be a
separate package, just not the minimal one to build out of tree modules,
etc.




>
> SDK building with such a support is good/cool. But sometimes, before
> introducing SDK, some tests should be done on target. NO need to
> optionally include built-in layer hello-world driver example. Since I
> (or you name the person) have own test drivers, which will be imported
> out of tree, externally, to the target test bed!
>
>
I never use the SDK myself, so you are not alone in not going to it first.
Hopefully I'll get some new patches out in the coming month before summer
holidays really kick in.

Bruce



> Just thinking loud...
>
> Zoran
> _______
>
> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield <bruce.ashfield@gmail.com>
> wrote:
> >
> >
> >
> > On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >>
> >> > That's correct. That command only adds the kernel source and
> >> > build infrastructure to the SDK, not to your target image. You'd still
> >> > need to arrange to have the kernel-devsrc package installed on the
> >> > target image if you want it on the board's rootfs. How you arrange
> >> > to have the package installed to the image varies with the image
> >> > (since they all don't have the same image install variables, etc).
> >>
> >> And here is a $1,000,000 USD question? How to do it on Poky (as
> >> example of what you have stated in RED)? ;-)
> >>
> >> In other words: how to arrange it on Poky (as a Referent example)?
> >
> >
> > The core-image-kernel-dev image is how I do all my on target testing
> when I introduce a new reference kernel for a release. And IIRC the
> autobuilders are using a sato based image (Richard could confirm more
> easily that I could what image type the autobuilders are using for
> hello-world on target module tests).
> >
> > Bruce
> >
> >
> >>
> >>
> >> Thank you,
> >> Zoran
> >> _______
> >>
> >>
> >> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <
> bruce.ashfield@gmail.com> wrote:
> >>>
> >>>
> >>>
> >>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >>>>
> >>>> Hello Chris, Bruce,
> >>>>
> >>>> I have some additional data to share with you both, since I have tried
> >>>> something. And here is my take on the things!
> >>>>
> >>>> > 1. Build using a bb recipe.
> >>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an
> example.
> >>>> > You just need to add meta-skeleton to your bblayers.conf and then
> >>>> >  bitbake hello-mod
> >>>>
> >>>> I looked into this example, and, yes, it is classic kernel module
> >>>> definition out of the tree. With some outdated data, all cool, the
> >>>> YOCTO designer should take care himself to fix these data, if using
> >>>> this stuff.
> >>>>
> >>>> But this is NOT mandatory, since I can add out of the tree module NOT
> >>>> actually using built-in module. I just use .../tmp/deploy/images/bbb/*
> >>>> generated stuff, since I have automated scripts which are bringing all
> >>>> these on my BBB target. Then I tftp my source code module to the
> >>>> target.
> >>>>
> >>>> > 2. Build from the SDK:
> >>>> > First, add the kernel source to the SDK by adding this to
> conf/local.conf
> >>>> >  TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >>>>
> >>>> YES, this is THE command which should generate
> >>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
> >>>> local.conf and after deleting kernel, then regenerating bitbake -k
> >>>> core-image-minimal does not bring this path into the rootfs image!?
> >>>
> >>>
> >>> That's correct. That command only adds the kernel source and build
> infrastructure to the SDK, not to your target image. You'd still need to
> arrange to have the kernel-devsrc package installed on the target image if
> you want it on the board's rootfs. How you arrange to have the package
> installed to the image varies with the image (since they all don't have the
> same image install variables, etc).
> >>>
> >>>
> >>>>
> >>>>
> >>>> I did it actually using meta-bbb, and using poky referent distro as
> >>>> two additional layers to the more complex bbb image!
> >>>> https://github.com/jumpnow/meta-bbb.git
> >>>>
> >>>> The (KAS - you can figure out out of it local.conf) script I am using
> >>>> to build such a BBB image is here:
> >>>>
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
> >>>>
> >>>> I did not try it with BBB reference poky only! Maybe I should try it
> >>>> as only referent poky? What do you think?
> >>>>
> >>>> Does in this case is SDK build really mandatory??? Should NOT be!
> >>>>
> >>>
> >>> You only do the SDK steps if you want to support building out of tree
> modules in an SDK install. So it is not mandatory for on target module
> builds.
> >>>
> >>> Bruce
> >>>
> >>>
> >>>>
> >>>> > Once the SDK is installed, generate the kernel headers:
> >>>> >  sudo -i
> >>>> >  .
> /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >>>> >  cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >>>> >  cd /usr/src/kernel
> >>>> >  make oldconfig scripts
> >>>> >  exit
> >>>>
> >>>> This is in nutshell the same what I did (a bit different) for Embedded
> >>>> Debian. This is already on the target BBB, NOT while building YOCTO
> >>>> BBB image!
> >>>>
> >>>> > Finally, build your module using a Makefile like this
> >>>> >  obj-m := hello-mod.o
> >>>> >  all:
> >>>> >        make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
> >>>>
> >>>> As said before: bringing my own module into the target BBB (I have my
> >>>> own examples, and I build them on the target with the almost the same
> >>>> Makefiles)
> >>>>
> >>>> Zoran
> >>>> _______
> >>>>
> >>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk>
> wrote:
> >>>> >
> >>>> > Hi Zoran,
> >>>> >
> >>>> > There are two ways to do this
> >>>> >
> >>>> > 1. Build using a bb recipe.
> >>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an
> example.
> >>>> > You just need to add meta-skeleton to your bblaysers.conf and then
> >>>> >   bitbake hello-mod
> >>>> >
> >>>> >
> >>>> > 2. Build from the SDK:
> >>>> > First, add the kernel source to the SDK by adding this to
> conf/local/conf
> >>>> >   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >>>> >
> >>>> > Then build the SDK
> >>>> >   bitbake -c populate_sdk [your image recipe]
> >>>> >
> >>>> > Once the SDK is installed, generate the kernel headers:
> >>>> >   sudo -i
> >>>> >   .
> /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >>>> >   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >>>> >   cd /usr/src/kernel
> >>>> >   make oldconfig scripts
> >>>> >   exit
> >>>> >
> >>>> > Finally, build your module using a Makefile like this
> >>>> >
> >>>> >   obj-m := hello-mod.o
> >>>> >   all:
> >>>> >         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
> >>>> >
> >>>> >
> >>>> > HTH,
> >>>> > Chris
> >>>> >
> >>>> > On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
> >>>> > > Hello to the YOCTO community,
> >>>> > >
> >>>> > > I am using (to build the target for Beagle Bone Black) the
> following script:
> >>>> > > https://github.com/ZoranStojsavljevic/bbb-yocto
> >>>> > >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
> >>>> > >
> >>>> > > The latest kernel I am using from the following repo:
> >>>> > > https://github.com/jumpnow/meta-bbb
> >>>> > >
> >>>> > > Is kernel 5.0.14 .
> >>>> > >
> >>>> > > Here is the snippet of the boot traces:
> >>>> > > Starting kernel ...
> >>>> > >
> >>>> > > [    0.000000] Booting Linux on physical CPU 0x0
> >>>> > > [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host)
> (gcc
> >>>> > > version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> >>>> > > [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2
> (ARMv7), cr=10c5387d
> >>>> > > [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT
> aliasing
> >>>> > > instruction cache
> >>>> > > [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
> >>>> > > [    0.000000] Memory policy: Data cache writeback
> >>>> > > [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> >>>> > > [    0.000000] CPU: All CPU(s) started in SVC mode.
> >>>> > > [    0.000000] AM335X ES2.1 (sgx neon)
> >>>> > > [    0.000000] random: get_random_bytes called from
> >>>> > > start_kernel+0xa4/0x460 with crng_init=0
> >>>> > > [    0.000000] Built 1 zonelists, mobility grouping on.  Total
> pages: 130048
> >>>> > > [    0.000000] Kernel command line: console=ttyO0,115200n8
> >>>> > > root=/dev/ram0 ip=dhcp
> >>>> > >
> >>>> > > According to the documentation, the following:
> >>>> > > 2.10.1. Building Out-of-Tree Modules on the Target
> >>>> > >
> https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
> >>>> > >
> >>>> > > I tried to find /usr/src/kernels/5.0.14... Directory, since I see
> >>>> > > from the build that kernel-dev and kernel-devsrc are included:
> >>>> > > [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> >>>> > > core-image-kernel-dev                                 :1.0-r0
> >>>> > > kernel-devsrc                                         :1.0-r0
> >>>> > > kernel-selftest                                       :1.0-r0
> >>>> > >
> >>>> > > THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
> >>>> > > directory at all!?
> >>>> > >
> >>>> > > Two questions here?
> >>>> > > [1] Do you have any advice on this problem (what I am missing
> here)?
> >>>> > > [2] Alternative to [1]: how I can use cross compiler from
> >>>> > > .../build/tmp to build Out-of-Tree Module for the BBB target on
> the
> >>>> > > host?
> >>>> > >
> >>>> > > Thank you,
> >>>> > > Zoran
> >>>> > > _______
> >>>> > >
> >>>> >
> >>>> >
> >>>> > --
> >>>> > Chris Simmonds, trainer and consultant at 2net
> >>>> > http://www.2net.co.uk
> >>>> > Author of "Mastering Embedded Linux Programming"
> >>>
> >>>
> >>>
> >>> --
> >>> - Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end
> >>> - "Use the force Harry" - Gandalf, Star Trek II
> >>>
> >
> >
> > --
> > - Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end
> > - "Use the force Harry" - Gandalf, Star Trek II
> >
>


-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

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Re: Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

After some tests (and I had other problems to take care of, as well),
here is the following:

> These have all been discussed off an on over the past 5 years.
> I can't get at bugzilla right now, but all the details are logged in cases.
> A survey of all the distros, their kernel package, etc, were all looked at.
> We had to balance the traditional packaging with some new concepts
> and landed with what we have now.

I tried several tests. This is my final conclusion (two cases):
https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt

The kernel issue is described here: there is need to have the YOCTO
minimum configuration with the kernel setup:
[1] The entire kernel source code in:
/usr/src/kernel/`uname-r`/<kernel source code>
[2] The header files in: /usr/src/kernel/`uname-r`/<header file
directory structures>

Point [1] is achieved with the following local.config file:
https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf

Namely, with the following snippets in the local.conf:
TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
packagegroup-core-buildessential kernel-devsrc"
KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
packagegroup-core-buildessential kernel-devsrc"
KERNEL_DEV_MODULE = "kernel-modules"
CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
${KERNEL_DEV_TOOLS} \
systemtap \
"

Problem with this approach is that such a kernel makes the rootfs too
big and impractical:
-rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
core-image-minimal-beaglebone.rootfs.tar.xz

The main issue is point [2]: how to achieve it?
The suggestion is to introduce the new package in YOCTO kernel,
called: kernel-headers
The OBVIOUS benefit is that it will serve to the purpose of building
modules out of the tree on the target with
minimal mpact to rootfs!

Thank you,
Zoran Stojsavljevic
_______

On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
<bruce.ashfield@gmail.com> wrote:
>
>
>
> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>>
>> > The core-image-kernel-dev image is how I do all my on target
>> > testing when I introduce a new reference kernel for a release.
>>
>> Maybe you are correct. Maybe I should use/add in my local.conf the following:
>>
>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
>> packagegroup-core-buildessential kernel-devsrc"
>> KERNEL_DEV_MODULE ?= "kernel-modules"
>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>>                              ${KERNEL_DEV_TOOLS} \
>>                              systemtap \
>>                             "
>> I need to try these... Maybe this addendum will solve the $1 mio USD problem?!
>>
>> > And IIRC the autobuilders are using a sato based image (Richard
>> > could confirm more easily that I could what image type the
>> > autobuilders are using for hello-world on target module tests).
>>
>> I am just advertising something more simple. To have mandatory
>> /lib/modules/`uname -r` directory. And introduce few more packages, as
>> Fedora distro, for example, has: kernel-headers (assuming YOCTO
>> rootfs, the following will be installed: /usr/src/kernel/`uname
>> -r`/<header file directory structures>. This also makes addition of
>> /lib/modules/`uname -r`/build file (which is soft link to
>> usr/src/kernel/`uname -r`).
>
>
> These have all been discussed off an on over the past 5 years. I can't get at bugzilla right now, but all the details are logged in cases. A survey of all the distros, their kernel package, etc, were all looked at. We had to balance the traditional packaging with some new concepts and landed with what we have now.
>
>
>>
>> Or kernel-devel package. Then, the whole current kernel source code
>> will be introduced, and also support for it.
>
>
> There's a case for this one as well, I'll probably have it done for the fall release. But our devsrc used to pretty much be the full source it has now been pruned down to something more manageable.  There are definitely some cases for having the full source on the target again, and it will be a separate package, just not the minimal one to build out of tree modules, etc.
>
>
>
>>
>>
>> SDK building with such a support is good/cool. But sometimes, before
>> introducing SDK, some tests should be done on target. NO need to
>> optionally include built-in layer hello-world driver example. Since I
>> (or you name the person) have own test drivers, which will be imported
>> out of tree, externally, to the target test bed!
>>
>
> I never use the SDK myself, so you are not alone in not going to it first. Hopefully I'll get some new patches out in the coming month before summer holidays really kick in.
>
> Bruce
>
>
>>
>> Just thinking loud...
>>
>> Zoran
>> _______
>>
>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>> >
>> >
>> >
>> > On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>> >>
>> >> > That's correct. That command only adds the kernel source and
>> >> > build infrastructure to the SDK, not to your target image. You'd still
>> >> > need to arrange to have the kernel-devsrc package installed on the
>> >> > target image if you want it on the board's rootfs. How you arrange
>> >> > to have the package installed to the image varies with the image
>> >> > (since they all don't have the same image install variables, etc).
>> >>
>> >> And here is a $1,000,000 USD question? How to do it on Poky (as
>> >> example of what you have stated in RED)? ;-)
>> >>
>> >> In other words: how to arrange it on Poky (as a Referent example)?
>> >
>> >
>> > The core-image-kernel-dev image is how I do all my on target testing when I introduce a new reference kernel for a release. And IIRC the autobuilders are using a sato based image (Richard could confirm more easily that I could what image type the autobuilders are using for hello-world on target module tests).
>> >
>> > Bruce
>> >
>> >
>> >>
>> >>
>> >> Thank you,
>> >> Zoran
>> >> _______
>> >>
>> >>
>> >> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>> >>>
>> >>>
>> >>>
>> >>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>> >>>>
>> >>>> Hello Chris, Bruce,
>> >>>>
>> >>>> I have some additional data to share with you both, since I have tried
>> >>>> something. And here is my take on the things!
>> >>>>
>> >>>> > 1. Build using a bb recipe.
>> >>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>> >>>> > You just need to add meta-skeleton to your bblayers.conf and then
>> >>>> >  bitbake hello-mod
>> >>>>
>> >>>> I looked into this example, and, yes, it is classic kernel module
>> >>>> definition out of the tree. With some outdated data, all cool, the
>> >>>> YOCTO designer should take care himself to fix these data, if using
>> >>>> this stuff.
>> >>>>
>> >>>> But this is NOT mandatory, since I can add out of the tree module NOT
>> >>>> actually using built-in module. I just use .../tmp/deploy/images/bbb/*
>> >>>> generated stuff, since I have automated scripts which are bringing all
>> >>>> these on my BBB target. Then I tftp my source code module to the
>> >>>> target.
>> >>>>
>> >>>> > 2. Build from the SDK:
>> >>>> > First, add the kernel source to the SDK by adding this to conf/local.conf
>> >>>> >  TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>> >>>>
>> >>>> YES, this is THE command which should generate
>> >>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
>> >>>> local.conf and after deleting kernel, then regenerating bitbake -k
>> >>>> core-image-minimal does not bring this path into the rootfs image!?
>> >>>
>> >>>
>> >>> That's correct. That command only adds the kernel source and build infrastructure to the SDK, not to your target image. You'd still need to arrange to have the kernel-devsrc package installed on the target image if you want it on the board's rootfs. How you arrange to have the package installed to the image varies with the image (since they all don't have the same image install variables, etc).
>> >>>
>> >>>
>> >>>>
>> >>>>
>> >>>> I did it actually using meta-bbb, and using poky referent distro as
>> >>>> two additional layers to the more complex bbb image!
>> >>>> https://github.com/jumpnow/meta-bbb.git
>> >>>>
>> >>>> The (KAS - you can figure out out of it local.conf) script I am using
>> >>>> to build such a BBB image is here:
>> >>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>> >>>>
>> >>>> I did not try it with BBB reference poky only! Maybe I should try it
>> >>>> as only referent poky? What do you think?
>> >>>>
>> >>>> Does in this case is SDK build really mandatory??? Should NOT be!
>> >>>>
>> >>>
>> >>> You only do the SDK steps if you want to support building out of tree modules in an SDK install. So it is not mandatory for on target module builds.
>> >>>
>> >>> Bruce
>> >>>
>> >>>
>> >>>>
>> >>>> > Once the SDK is installed, generate the kernel headers:
>> >>>> >  sudo -i
>> >>>> >  . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>> >>>> >  cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>> >>>> >  cd /usr/src/kernel
>> >>>> >  make oldconfig scripts
>> >>>> >  exit
>> >>>>
>> >>>> This is in nutshell the same what I did (a bit different) for Embedded
>> >>>> Debian. This is already on the target BBB, NOT while building YOCTO
>> >>>> BBB image!
>> >>>>
>> >>>> > Finally, build your module using a Makefile like this
>> >>>> >  obj-m := hello-mod.o
>> >>>> >  all:
>> >>>> >        make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>> >>>>
>> >>>> As said before: bringing my own module into the target BBB (I have my
>> >>>> own examples, and I build them on the target with the almost the same
>> >>>> Makefiles)
>> >>>>
>> >>>> Zoran
>> >>>> _______
>> >>>>
>> >>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk> wrote:
>> >>>> >
>> >>>> > Hi Zoran,
>> >>>> >
>> >>>> > There are two ways to do this
>> >>>> >
>> >>>> > 1. Build using a bb recipe.
>> >>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>> >>>> > You just need to add meta-skeleton to your bblaysers.conf and then
>> >>>> >   bitbake hello-mod
>> >>>> >
>> >>>> >
>> >>>> > 2. Build from the SDK:
>> >>>> > First, add the kernel source to the SDK by adding this to conf/local/conf
>> >>>> >   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>> >>>> >
>> >>>> > Then build the SDK
>> >>>> >   bitbake -c populate_sdk [your image recipe]
>> >>>> >
>> >>>> > Once the SDK is installed, generate the kernel headers:
>> >>>> >   sudo -i
>> >>>> >   . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>> >>>> >   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>> >>>> >   cd /usr/src/kernel
>> >>>> >   make oldconfig scripts
>> >>>> >   exit
>> >>>> >
>> >>>> > Finally, build your module using a Makefile like this
>> >>>> >
>> >>>> >   obj-m := hello-mod.o
>> >>>> >   all:
>> >>>> >         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>> >>>> >
>> >>>> >
>> >>>> > HTH,
>> >>>> > Chris
>> >>>> >
>> >>>> > On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>> >>>> > > Hello to the YOCTO community,
>> >>>> > >
>> >>>> > > I am using (to build the target for Beagle Bone Black) the following script:
>> >>>> > > https://github.com/ZoranStojsavljevic/bbb-yocto
>> >>>> > > https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>> >>>> > >
>> >>>> > > The latest kernel I am using from the following repo:
>> >>>> > > https://github.com/jumpnow/meta-bbb
>> >>>> > >
>> >>>> > > Is kernel 5.0.14 .
>> >>>> > >
>> >>>> > > Here is the snippet of the boot traces:
>> >>>> > > Starting kernel ...
>> >>>> > >
>> >>>> > > [    0.000000] Booting Linux on physical CPU 0x0
>> >>>> > > [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
>> >>>> > > version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>> >>>> > > [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
>> >>>> > > [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
>> >>>> > > instruction cache
>> >>>> > > [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
>> >>>> > > [    0.000000] Memory policy: Data cache writeback
>> >>>> > > [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>> >>>> > > [    0.000000] CPU: All CPU(s) started in SVC mode.
>> >>>> > > [    0.000000] AM335X ES2.1 (sgx neon)
>> >>>> > > [    0.000000] random: get_random_bytes called from
>> >>>> > > start_kernel+0xa4/0x460 with crng_init=0
>> >>>> > > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 130048
>> >>>> > > [    0.000000] Kernel command line: console=ttyO0,115200n8
>> >>>> > > root=/dev/ram0 ip=dhcp
>> >>>> > >
>> >>>> > > According to the documentation, the following:
>> >>>> > > 2.10.1. Building Out-of-Tree Modules on the Target
>> >>>> > > https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>> >>>> > >
>> >>>> > > I tried to find /usr/src/kernels/5.0.14... Directory, since I see
>> >>>> > > from the build that kernel-dev and kernel-devsrc are included:
>> >>>> > > [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>> >>>> > > core-image-kernel-dev                                 :1.0-r0
>> >>>> > > kernel-devsrc                                         :1.0-r0
>> >>>> > > kernel-selftest                                       :1.0-r0
>> >>>> > >
>> >>>> > > THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
>> >>>> > > directory at all!?
>> >>>> > >
>> >>>> > > Two questions here?
>> >>>> > > [1] Do you have any advice on this problem (what I am missing here)?
>> >>>> > > [2] Alternative to [1]: how I can use cross compiler from
>> >>>> > > .../build/tmp to build Out-of-Tree Module for the BBB target on the
>> >>>> > > host?
>> >>>> > >
>> >>>> > > Thank you,
>> >>>> > > Zoran
>> >>>> > > _______
>> >>>> > >
>> >>>> >
>> >>>> >
>> >>>> > --
>> >>>> > Chris Simmonds, trainer and consultant at 2net
>> >>>> > http://www.2net.co.uk
>> >>>> > Author of "Mastering Embedded Linux Programming"
>> >>>
>> >>>
>> >>>
>> >>> --
>> >>> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>> >>> - "Use the force Harry" - Gandalf, Star Trek II
>> >>>
>> >
>> >
>> > --
>> > - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>> > - "Use the force Harry" - Gandalf, Star Trek II
>> >
>
>
>
> --
> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
> - "Use the force Harry" - Gandalf, Star Trek II
>

Re: Building Out-of-Tree Modules on the BBB Target

[Bruce Ashfield]

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On Thu, May 23, 2019 at 6:32 AM Zoran Stojsavljevic <
zoran.stojsavljevic@gmail.com> wrote:

> After some tests (and I had other problems to take care of, as well),
> here is the following:
>
> > These have all been discussed off an on over the past 5 years.
> > I can't get at bugzilla right now, but all the details are logged in
> cases.
> > A survey of all the distros, their kernel package, etc, were all looked
> at.
> > We had to balance the traditional packaging with some new concepts
> > and landed with what we have now.
>
> I tried several tests. This is my final conclusion (two cases):
>
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
>
> The kernel issue is described here: there is need to have the YOCTO
> minimum configuration with the kernel setup:
> [1] The entire kernel source code in:
> /usr/src/kernel/`uname-r`/<kernel source code>
> [2] The header files in: /usr/src/kernel/`uname-r`/<header file
> directory structures>
>
> Point [1] is achieved with the following local.config file:
>
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
>
> Namely, with the following snippets in the local.conf:
> TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
> packagegroup-core-buildessential kernel-devsrc"
> KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
> packagegroup-core-buildessential kernel-devsrc"
> KERNEL_DEV_MODULE = "kernel-modules"
> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
> ${KERNEL_DEV_TOOLS} \
> systemtap \
> "
>
> Problem with this approach is that such a kernel makes the rootfs too
> big and impractical:
> -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
> core-image-minimal-beaglebone.rootfs.tar.xz
>
> The main issue is point [2]: how to achieve it?
> The suggestion is to introduce the new package in YOCTO kernel,
> called: kernel-headers
> The OBVIOUS benefit is that it will serve to the purpose of building
> modules out of the tree on the target with
> minimal mpact to rootfs!
>

There are already 2.8 development items for some new, optional kernel
packages. One for source and one for headers.
So in the coming months, things will be different.

That being said, they are optional. I might be misreading, but what exactly
are you trying to build that requires that specific structure ? We are both
rebuilding the entire kernel and out of tree modules all the time with the
existing structure/path of the on-target installs.

kernel-devsrc itself is a small package (size wise), so it shouldn't be the
cause of your expanded rootfs footprint.

Bruce



>
> Thank you,
> Zoran Stojsavljevic
> _______
>
> On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
> <bruce.ashfield@gmail.com> wrote:
> >
> >
> >
> > On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >>
> >> > The core-image-kernel-dev image is how I do all my on target
> >> > testing when I introduce a new reference kernel for a release.
> >>
> >> Maybe you are correct. Maybe I should use/add in my local.conf the
> following:
> >>
> >> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
> >> packagegroup-core-buildessential kernel-devsrc"
> >> KERNEL_DEV_MODULE ?= "kernel-modules"
> >> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
> >>                              ${KERNEL_DEV_TOOLS} \
> >>                              systemtap \
> >>                             "
> >> I need to try these... Maybe this addendum will solve the $1 mio USD
> problem?!
> >>
> >> > And IIRC the autobuilders are using a sato based image (Richard
> >> > could confirm more easily that I could what image type the
> >> > autobuilders are using for hello-world on target module tests).
> >>
> >> I am just advertising something more simple. To have mandatory
> >> /lib/modules/`uname -r` directory. And introduce few more packages, as
> >> Fedora distro, for example, has: kernel-headers (assuming YOCTO
> >> rootfs, the following will be installed: /usr/src/kernel/`uname
> >> -r`/<header file directory structures>. This also makes addition of
> >> /lib/modules/`uname -r`/build file (which is soft link to
> >> usr/src/kernel/`uname -r`).
> >
> >
> > These have all been discussed off an on over the past 5 years. I can't
> get at bugzilla right now, but all the details are logged in cases. A
> survey of all the distros, their kernel package, etc, were all looked at.
> We had to balance the traditional packaging with some new concepts and
> landed with what we have now.
> >
> >
> >>
> >> Or kernel-devel package. Then, the whole current kernel source code
> >> will be introduced, and also support for it.
> >
> >
> > There's a case for this one as well, I'll probably have it done for the
> fall release. But our devsrc used to pretty much be the full source it has
> now been pruned down to something more manageable.  There are definitely
> some cases for having the full source on the target again, and it will be a
> separate package, just not the minimal one to build out of tree modules,
> etc.
> >
> >
> >
> >>
> >>
> >> SDK building with such a support is good/cool. But sometimes, before
> >> introducing SDK, some tests should be done on target. NO need to
> >> optionally include built-in layer hello-world driver example. Since I
> >> (or you name the person) have own test drivers, which will be imported
> >> out of tree, externally, to the target test bed!
> >>
> >
> > I never use the SDK myself, so you are not alone in not going to it
> first. Hopefully I'll get some new patches out in the coming month before
> summer holidays really kick in.
> >
> > Bruce
> >
> >
> >>
> >> Just thinking loud...
> >>
> >> Zoran
> >> _______
> >>
> >> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield <
> bruce.ashfield@gmail.com> wrote:
> >> >
> >> >
> >> >
> >> > On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >> >>
> >> >> > That's correct. That command only adds the kernel source and
> >> >> > build infrastructure to the SDK, not to your target image. You'd
> still
> >> >> > need to arrange to have the kernel-devsrc package installed on the
> >> >> > target image if you want it on the board's rootfs. How you arrange
> >> >> > to have the package installed to the image varies with the image
> >> >> > (since they all don't have the same image install variables, etc).
> >> >>
> >> >> And here is a $1,000,000 USD question? How to do it on Poky (as
> >> >> example of what you have stated in RED)? ;-)
> >> >>
> >> >> In other words: how to arrange it on Poky (as a Referent example)?
> >> >
> >> >
> >> > The core-image-kernel-dev image is how I do all my on target testing
> when I introduce a new reference kernel for a release. And IIRC the
> autobuilders are using a sato based image (Richard could confirm more
> easily that I could what image type the autobuilders are using for
> hello-world on target module tests).
> >> >
> >> > Bruce
> >> >
> >> >
> >> >>
> >> >>
> >> >> Thank you,
> >> >> Zoran
> >> >> _______
> >> >>
> >> >>
> >> >> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <
> bruce.ashfield@gmail.com> wrote:
> >> >>>
> >> >>>
> >> >>>
> >> >>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >> >>>>
> >> >>>> Hello Chris, Bruce,
> >> >>>>
> >> >>>> I have some additional data to share with you both, since I have
> tried
> >> >>>> something. And here is my take on the things!
> >> >>>>
> >> >>>> > 1. Build using a bb recipe.
> >> >>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an
> example.
> >> >>>> > You just need to add meta-skeleton to your bblayers.conf and then
> >> >>>> >  bitbake hello-mod
> >> >>>>
> >> >>>> I looked into this example, and, yes, it is classic kernel module
> >> >>>> definition out of the tree. With some outdated data, all cool, the
> >> >>>> YOCTO designer should take care himself to fix these data, if using
> >> >>>> this stuff.
> >> >>>>
> >> >>>> But this is NOT mandatory, since I can add out of the tree module
> NOT
> >> >>>> actually using built-in module. I just use
> .../tmp/deploy/images/bbb/*
> >> >>>> generated stuff, since I have automated scripts which are bringing
> all
> >> >>>> these on my BBB target. Then I tftp my source code module to the
> >> >>>> target.
> >> >>>>
> >> >>>> > 2. Build from the SDK:
> >> >>>> > First, add the kernel source to the SDK by adding this to
> conf/local.conf
> >> >>>> >  TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >> >>>>
> >> >>>> YES, this is THE command which should generate
> >> >>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
> >> >>>> local.conf and after deleting kernel, then regenerating bitbake -k
> >> >>>> core-image-minimal does not bring this path into the rootfs image!?
> >> >>>
> >> >>>
> >> >>> That's correct. That command only adds the kernel source and build
> infrastructure to the SDK, not to your target image. You'd still need to
> arrange to have the kernel-devsrc package installed on the target image if
> you want it on the board's rootfs. How you arrange to have the package
> installed to the image varies with the image (since they all don't have the
> same image install variables, etc).
> >> >>>
> >> >>>
> >> >>>>
> >> >>>>
> >> >>>> I did it actually using meta-bbb, and using poky referent distro as
> >> >>>> two additional layers to the more complex bbb image!
> >> >>>> https://github.com/jumpnow/meta-bbb.git
> >> >>>>
> >> >>>> The (KAS - you can figure out out of it local.conf) script I am
> using
> >> >>>> to build such a BBB image is here:
> >> >>>>
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
> >> >>>>
> >> >>>> I did not try it with BBB reference poky only! Maybe I should try
> it
> >> >>>> as only referent poky? What do you think?
> >> >>>>
> >> >>>> Does in this case is SDK build really mandatory??? Should NOT be!
> >> >>>>
> >> >>>
> >> >>> You only do the SDK steps if you want to support building out of
> tree modules in an SDK install. So it is not mandatory for on target module
> builds.
> >> >>>
> >> >>> Bruce
> >> >>>
> >> >>>
> >> >>>>
> >> >>>> > Once the SDK is installed, generate the kernel headers:
> >> >>>> >  sudo -i
> >> >>>> >  .
> /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >> >>>> >  cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >> >>>> >  cd /usr/src/kernel
> >> >>>> >  make oldconfig scripts
> >> >>>> >  exit
> >> >>>>
> >> >>>> This is in nutshell the same what I did (a bit different) for
> Embedded
> >> >>>> Debian. This is already on the target BBB, NOT while building YOCTO
> >> >>>> BBB image!
> >> >>>>
> >> >>>> > Finally, build your module using a Makefile like this
> >> >>>> >  obj-m := hello-mod.o
> >> >>>> >  all:
> >> >>>> >        make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
> >> >>>>
> >> >>>> As said before: bringing my own module into the target BBB (I have
> my
> >> >>>> own examples, and I build them on the target with the almost the
> same
> >> >>>> Makefiles)
> >> >>>>
> >> >>>> Zoran
> >> >>>> _______
> >> >>>>
> >> >>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk>
> wrote:
> >> >>>> >
> >> >>>> > Hi Zoran,
> >> >>>> >
> >> >>>> > There are two ways to do this
> >> >>>> >
> >> >>>> > 1. Build using a bb recipe.
> >> >>>> > Take a look at meta-skeleton/recipes-kernel/hello-mod for an
> example.
> >> >>>> > You just need to add meta-skeleton to your bblaysers.conf and
> then
> >> >>>> >   bitbake hello-mod
> >> >>>> >
> >> >>>> >
> >> >>>> > 2. Build from the SDK:
> >> >>>> > First, add the kernel source to the SDK by adding this to
> conf/local/conf
> >> >>>> >   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >> >>>> >
> >> >>>> > Then build the SDK
> >> >>>> >   bitbake -c populate_sdk [your image recipe]
> >> >>>> >
> >> >>>> > Once the SDK is installed, generate the kernel headers:
> >> >>>> >   sudo -i
> >> >>>> >   .
> /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >> >>>> >   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >> >>>> >   cd /usr/src/kernel
> >> >>>> >   make oldconfig scripts
> >> >>>> >   exit
> >> >>>> >
> >> >>>> > Finally, build your module using a Makefile like this
> >> >>>> >
> >> >>>> >   obj-m := hello-mod.o
> >> >>>> >   all:
> >> >>>> >         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
> >> >>>> >
> >> >>>> >
> >> >>>> > HTH,
> >> >>>> > Chris
> >> >>>> >
> >> >>>> > On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
> >> >>>> > > Hello to the YOCTO community,
> >> >>>> > >
> >> >>>> > > I am using (to build the target for Beagle Bone Black) the
> following script:
> >> >>>> > > https://github.com/ZoranStojsavljevic/bbb-yocto
> >> >>>> > >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
> >> >>>> > >
> >> >>>> > > The latest kernel I am using from the following repo:
> >> >>>> > > https://github.com/jumpnow/meta-bbb
> >> >>>> > >
> >> >>>> > > Is kernel 5.0.14 .
> >> >>>> > >
> >> >>>> > > Here is the snippet of the boot traces:
> >> >>>> > > Starting kernel ...
> >> >>>> > >
> >> >>>> > > [    0.000000] Booting Linux on physical CPU 0x0
> >> >>>> > > [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host)
> (gcc
> >> >>>> > > version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> >> >>>> > > [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2
> (ARMv7), cr=10c5387d
> >> >>>> > > [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT
> aliasing
> >> >>>> > > instruction cache
> >> >>>> > > [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone
> Black
> >> >>>> > > [    0.000000] Memory policy: Data cache writeback
> >> >>>> > > [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> >> >>>> > > [    0.000000] CPU: All CPU(s) started in SVC mode.
> >> >>>> > > [    0.000000] AM335X ES2.1 (sgx neon)
> >> >>>> > > [    0.000000] random: get_random_bytes called from
> >> >>>> > > start_kernel+0xa4/0x460 with crng_init=0
> >> >>>> > > [    0.000000] Built 1 zonelists, mobility grouping on.  Total
> pages: 130048
> >> >>>> > > [    0.000000] Kernel command line: console=ttyO0,115200n8
> >> >>>> > > root=/dev/ram0 ip=dhcp
> >> >>>> > >
> >> >>>> > > According to the documentation, the following:
> >> >>>> > > 2.10.1. Building Out-of-Tree Modules on the Target
> >> >>>> > >
> https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
> >> >>>> > >
> >> >>>> > > I tried to find /usr/src/kernels/5.0.14... Directory, since I
> see
> >> >>>> > > from the build that kernel-dev and kernel-devsrc are included:
> >> >>>> > > [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> >> >>>> > > core-image-kernel-dev                                 :1.0-r0
> >> >>>> > > kernel-devsrc                                         :1.0-r0
> >> >>>> > > kernel-selftest                                       :1.0-r0
> >> >>>> > >
> >> >>>> > > THE PROBLEM: But I could not find ob BBB target
> /usr/src/kernels
> >> >>>> > > directory at all!?
> >> >>>> > >
> >> >>>> > > Two questions here?
> >> >>>> > > [1] Do you have any advice on this problem (what I am missing
> here)?
> >> >>>> > > [2] Alternative to [1]: how I can use cross compiler from
> >> >>>> > > .../build/tmp to build Out-of-Tree Module for the BBB target
> on the
> >> >>>> > > host?
> >> >>>> > >
> >> >>>> > > Thank you,
> >> >>>> > > Zoran
> >> >>>> > > _______
> >> >>>> > >
> >> >>>> >
> >> >>>> >
> >> >>>> > --
> >> >>>> > Chris Simmonds, trainer and consultant at 2net
> >> >>>> > http://www.2net.co.uk
> >> >>>> > Author of "Mastering Embedded Linux Programming"
> >> >>>
> >> >>>
> >> >>>
> >> >>> --
> >> >>> - Thou shalt not follow the NULL pointer, for chaos and madness
> await thee at its end
> >> >>> - "Use the force Harry" - Gandalf, Star Trek II
> >> >>>
> >> >
> >> >
> >> > --
> >> > - Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end
> >> > - "Use the force Harry" - Gandalf, Star Trek II
> >> >
> >
> >
> >
> > --
> > - Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end
> > - "Use the force Harry" - Gandalf, Star Trek II
> >
>


-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

[-- Attachment #2: Type: text/html, Size: 25029 bytes --]

Re: Building Out-of-Tree Modules on the BBB Target

[Khem Raj]

On 5/23/19 3:32 AM, Zoran Stojsavljevic wrote:
> After some tests (and I had other problems to take care of, as well),
> here is the following:
> 
>> These have all been discussed off an on over the past 5 years.
>> I can't get at bugzilla right now, but all the details are logged in cases.
>> A survey of all the distros, their kernel package, etc, were all looked at.
>> We had to balance the traditional packaging with some new concepts
>> and landed with what we have now.
> 
> I tried several tests. This is my final conclusion (two cases):
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
> 
> The kernel issue is described here: there is need to have the YOCTO
> minimum configuration with the kernel setup:
> [1] The entire kernel source code in:
> /usr/src/kernel/`uname-r`/<kernel source code>
> [2] The header files in: /usr/src/kernel/`uname-r`/<header file
> directory structures>
> 
> Point [1] is achieved with the following local.config file:
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
> 
> Namely, with the following snippets in the local.conf:
> TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
> packagegroup-core-buildessential kernel-devsrc"
> KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
> packagegroup-core-buildessential kernel-devsrc"
> KERNEL_DEV_MODULE = "kernel-modules"
> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
> ${KERNEL_DEV_TOOLS} \
> systemtap \
> "
> 
> Problem with this approach is that such a kernel makes the rootfs too
> big and impractical:
> -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
> core-image-minimal-beaglebone.rootfs.tar.xz
> 
> The main issue is point [2]: how to achieve it?
> The suggestion is to introduce the new package in YOCTO kernel,
> called: kernel-headers
> The OBVIOUS benefit is that it will serve to the purpose of building
> modules out of the tree on the target with
> minimal mpact to rootfs!

I think this is a fair suggestion. Having prebuilt kernel available
that contains the configuration and header files used in the build is 
all that is required for external modules to build in addition to 
toolchain, so maybe its worth a try to create such a package and then 
have kernel-source separated out which can be installed on top if one
needs

> 
> Thank you,
> Zoran Stojsavljevic
> _______
> 
> On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
> <bruce.ashfield@gmail.com> wrote:
>>
>>
>>
>> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>>>
>>>> The core-image-kernel-dev image is how I do all my on target
>>>> testing when I introduce a new reference kernel for a release.
>>>
>>> Maybe you are correct. Maybe I should use/add in my local.conf the following:
>>>
>>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
>>> packagegroup-core-buildessential kernel-devsrc"
>>> KERNEL_DEV_MODULE ?= "kernel-modules"
>>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>>>                               ${KERNEL_DEV_TOOLS} \
>>>                               systemtap \
>>>                              "
>>> I need to try these... Maybe this addendum will solve the $1 mio USD problem?!
>>>
>>>> And IIRC the autobuilders are using a sato based image (Richard
>>>> could confirm more easily that I could what image type the
>>>> autobuilders are using for hello-world on target module tests).
>>>
>>> I am just advertising something more simple. To have mandatory
>>> /lib/modules/`uname -r` directory. And introduce few more packages, as
>>> Fedora distro, for example, has: kernel-headers (assuming YOCTO
>>> rootfs, the following will be installed: /usr/src/kernel/`uname
>>> -r`/<header file directory structures>. This also makes addition of
>>> /lib/modules/`uname -r`/build file (which is soft link to
>>> usr/src/kernel/`uname -r`).
>>
>>
>> These have all been discussed off an on over the past 5 years. I can't get at bugzilla right now, but all the details are logged in cases. A survey of all the distros, their kernel package, etc, were all looked at. We had to balance the traditional packaging with some new concepts and landed with what we have now.
>>
>>
>>>
>>> Or kernel-devel package. Then, the whole current kernel source code
>>> will be introduced, and also support for it.
>>
>>
>> There's a case for this one as well, I'll probably have it done for the fall release. But our devsrc used to pretty much be the full source it has now been pruned down to something more manageable.  There are definitely some cases for having the full source on the target again, and it will be a separate package, just not the minimal one to build out of tree modules, etc.
>>
>>
>>
>>>
>>>
>>> SDK building with such a support is good/cool. But sometimes, before
>>> introducing SDK, some tests should be done on target. NO need to
>>> optionally include built-in layer hello-world driver example. Since I
>>> (or you name the person) have own test drivers, which will be imported
>>> out of tree, externally, to the target test bed!
>>>
>>
>> I never use the SDK myself, so you are not alone in not going to it first. Hopefully I'll get some new patches out in the coming month before summer holidays really kick in.
>>
>> Bruce
>>
>>
>>>
>>> Just thinking loud...
>>>
>>> Zoran
>>> _______
>>>
>>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>>>>
>>>>
>>>>
>>>> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>>>>>
>>>>>> That's correct. That command only adds the kernel source and
>>>>>> build infrastructure to the SDK, not to your target image. You'd still
>>>>>> need to arrange to have the kernel-devsrc package installed on the
>>>>>> target image if you want it on the board's rootfs. How you arrange
>>>>>> to have the package installed to the image varies with the image
>>>>>> (since they all don't have the same image install variables, etc).
>>>>>
>>>>> And here is a $1,000,000 USD question? How to do it on Poky (as
>>>>> example of what you have stated in RED)? ;-)
>>>>>
>>>>> In other words: how to arrange it on Poky (as a Referent example)?
>>>>
>>>>
>>>> The core-image-kernel-dev image is how I do all my on target testing when I introduce a new reference kernel for a release. And IIRC the autobuilders are using a sato based image (Richard could confirm more easily that I could what image type the autobuilders are using for hello-world on target module tests).
>>>>
>>>> Bruce
>>>>
>>>>
>>>>>
>>>>>
>>>>> Thank you,
>>>>> Zoran
>>>>> _______
>>>>>
>>>>>
>>>>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>>>>>>>
>>>>>>> Hello Chris, Bruce,
>>>>>>>
>>>>>>> I have some additional data to share with you both, since I have tried
>>>>>>> something. And here is my take on the things!
>>>>>>>
>>>>>>>> 1. Build using a bb recipe.
>>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>>>>>>>> You just need to add meta-skeleton to your bblayers.conf and then
>>>>>>>>   bitbake hello-mod
>>>>>>>
>>>>>>> I looked into this example, and, yes, it is classic kernel module
>>>>>>> definition out of the tree. With some outdated data, all cool, the
>>>>>>> YOCTO designer should take care himself to fix these data, if using
>>>>>>> this stuff.
>>>>>>>
>>>>>>> But this is NOT mandatory, since I can add out of the tree module NOT
>>>>>>> actually using built-in module. I just use .../tmp/deploy/images/bbb/*
>>>>>>> generated stuff, since I have automated scripts which are bringing all
>>>>>>> these on my BBB target. Then I tftp my source code module to the
>>>>>>> target.
>>>>>>>
>>>>>>>> 2. Build from the SDK:
>>>>>>>> First, add the kernel source to the SDK by adding this to conf/local.conf
>>>>>>>>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>>>>>>
>>>>>>> YES, this is THE command which should generate
>>>>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
>>>>>>> local.conf and after deleting kernel, then regenerating bitbake -k
>>>>>>> core-image-minimal does not bring this path into the rootfs image!?
>>>>>>
>>>>>>
>>>>>> That's correct. That command only adds the kernel source and build infrastructure to the SDK, not to your target image. You'd still need to arrange to have the kernel-devsrc package installed on the target image if you want it on the board's rootfs. How you arrange to have the package installed to the image varies with the image (since they all don't have the same image install variables, etc).
>>>>>>
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> I did it actually using meta-bbb, and using poky referent distro as
>>>>>>> two additional layers to the more complex bbb image!
>>>>>>> https://github.com/jumpnow/meta-bbb.git
>>>>>>>
>>>>>>> The (KAS - you can figure out out of it local.conf) script I am using
>>>>>>> to build such a BBB image is here:
>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>>>>>>>
>>>>>>> I did not try it with BBB reference poky only! Maybe I should try it
>>>>>>> as only referent poky? What do you think?
>>>>>>>
>>>>>>> Does in this case is SDK build really mandatory??? Should NOT be!
>>>>>>>
>>>>>>
>>>>>> You only do the SDK steps if you want to support building out of tree modules in an SDK install. So it is not mandatory for on target module builds.
>>>>>>
>>>>>> Bruce
>>>>>>
>>>>>>
>>>>>>>
>>>>>>>> Once the SDK is installed, generate the kernel headers:
>>>>>>>>   sudo -i
>>>>>>>>   . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>>>>>>>   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>>>>>>>   cd /usr/src/kernel
>>>>>>>>   make oldconfig scripts
>>>>>>>>   exit
>>>>>>>
>>>>>>> This is in nutshell the same what I did (a bit different) for Embedded
>>>>>>> Debian. This is already on the target BBB, NOT while building YOCTO
>>>>>>> BBB image!
>>>>>>>
>>>>>>>> Finally, build your module using a Makefile like this
>>>>>>>>   obj-m := hello-mod.o
>>>>>>>>   all:
>>>>>>>>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>>>>>>>
>>>>>>> As said before: bringing my own module into the target BBB (I have my
>>>>>>> own examples, and I build them on the target with the almost the same
>>>>>>> Makefiles)
>>>>>>>
>>>>>>> Zoran
>>>>>>> _______
>>>>>>>
>>>>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk> wrote:
>>>>>>>>
>>>>>>>> Hi Zoran,
>>>>>>>>
>>>>>>>> There are two ways to do this
>>>>>>>>
>>>>>>>> 1. Build using a bb recipe.
>>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>>>>>>>> You just need to add meta-skeleton to your bblaysers.conf and then
>>>>>>>>    bitbake hello-mod
>>>>>>>>
>>>>>>>>
>>>>>>>> 2. Build from the SDK:
>>>>>>>> First, add the kernel source to the SDK by adding this to conf/local/conf
>>>>>>>>    TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>>>>>>>
>>>>>>>> Then build the SDK
>>>>>>>>    bitbake -c populate_sdk [your image recipe]
>>>>>>>>
>>>>>>>> Once the SDK is installed, generate the kernel headers:
>>>>>>>>    sudo -i
>>>>>>>>    . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>>>>>>>    cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>>>>>>>    cd /usr/src/kernel
>>>>>>>>    make oldconfig scripts
>>>>>>>>    exit
>>>>>>>>
>>>>>>>> Finally, build your module using a Makefile like this
>>>>>>>>
>>>>>>>>    obj-m := hello-mod.o
>>>>>>>>    all:
>>>>>>>>          make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>>>>>>>>
>>>>>>>>
>>>>>>>> HTH,
>>>>>>>> Chris
>>>>>>>>
>>>>>>>> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>>>>>>>>> Hello to the YOCTO community,
>>>>>>>>>
>>>>>>>>> I am using (to build the target for Beagle Bone Black) the following script:
>>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto
>>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>>>>>>>>>
>>>>>>>>> The latest kernel I am using from the following repo:
>>>>>>>>> https://github.com/jumpnow/meta-bbb
>>>>>>>>>
>>>>>>>>> Is kernel 5.0.14 .
>>>>>>>>>
>>>>>>>>> Here is the snippet of the boot traces:
>>>>>>>>> Starting kernel ...
>>>>>>>>>
>>>>>>>>> [    0.000000] Booting Linux on physical CPU 0x0
>>>>>>>>> [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
>>>>>>>>> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>>>>>>>>> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
>>>>>>>>> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
>>>>>>>>> instruction cache
>>>>>>>>> [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
>>>>>>>>> [    0.000000] Memory policy: Data cache writeback
>>>>>>>>> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>>>>>>>>> [    0.000000] CPU: All CPU(s) started in SVC mode.
>>>>>>>>> [    0.000000] AM335X ES2.1 (sgx neon)
>>>>>>>>> [    0.000000] random: get_random_bytes called from
>>>>>>>>> start_kernel+0xa4/0x460 with crng_init=0
>>>>>>>>> [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 130048
>>>>>>>>> [    0.000000] Kernel command line: console=ttyO0,115200n8
>>>>>>>>> root=/dev/ram0 ip=dhcp
>>>>>>>>>
>>>>>>>>> According to the documentation, the following:
>>>>>>>>> 2.10.1. Building Out-of-Tree Modules on the Target
>>>>>>>>> https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>>>>>>>>>
>>>>>>>>> I tried to find /usr/src/kernels/5.0.14... Directory, since I see
>>>>>>>>> from the build that kernel-dev and kernel-devsrc are included:
>>>>>>>>> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>>>>>>>>> core-image-kernel-dev                                 :1.0-r0
>>>>>>>>> kernel-devsrc                                         :1.0-r0
>>>>>>>>> kernel-selftest                                       :1.0-r0
>>>>>>>>>
>>>>>>>>> THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
>>>>>>>>> directory at all!?
>>>>>>>>>
>>>>>>>>> Two questions here?
>>>>>>>>> [1] Do you have any advice on this problem (what I am missing here)?
>>>>>>>>> [2] Alternative to [1]: how I can use cross compiler from
>>>>>>>>> .../build/tmp to build Out-of-Tree Module for the BBB target on the
>>>>>>>>> host?
>>>>>>>>>
>>>>>>>>> Thank you,
>>>>>>>>> Zoran
>>>>>>>>> _______
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> --
>>>>>>>> Chris Simmonds, trainer and consultant at 2net
>>>>>>>> http://www.2net.co.uk
>>>>>>>> Author of "Mastering Embedded Linux Programming"
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>>>>>> - "Use the force Harry" - Gandalf, Star Trek II
>>>>>>
>>>>
>>>>
>>>> --
>>>> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>>>> - "Use the force Harry" - Gandalf, Star Trek II
>>>>
>>
>>
>>
>> --
>> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>> - "Use the force Harry" - Gandalf, Star Trek II
>>

Re: Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

[-- Attachment #1: Type: text/plain, Size: 17809 bytes --]

> I think this is a fair suggestion. Having prebuilt kernel available
> that contains the configuration and header files used in the build is
> all that is required for external modules to build in addition to
> toolchain, so maybe its worth a try to create such a package and then
> have kernel-source separated out which can be installed on top if one
> needs

I am man of experimental try-outs. So, in order to see how big kernel is,
I did the following:
Fedora 29 (which I am using as a host) with kernel-headers (NOT full
kernel source tree):
[vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ pwd
/usr/src/kernels/5.0.16-200.fc29.x86_64
[vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ du --summarize
*102124    . <<======= ~95MB*

Kernel.org kernel 5.0.6, the full kernel source tree size:
[vuser@fedora29-ssd linux-5.0.6]$ pwd
/home/vuser/projects/kernel.org/linux-5.0.6
[vuser@fedora29-ssd linux-5.0.6]$ du --summarize
*960592    . <<======= ~900MB*

These are ballpark numbers. You can draw conclusions for yourselves!

It is ~ 7x to 9x reduction in size. Having BBB's DDR2 of size 512MB,
and initramfs for testing purposes, in speaks for itself.

(I am aware that YOCTO kernels are less/smaller in size, but how smaller?)

Zoran
_______


On Fri, May 24, 2019 at 3:00 AM Khem Raj <raj.khem@gmail.com> wrote:

>
>
> On 5/23/19 3:32 AM, Zoran Stojsavljevic wrote:
> > After some tests (and I had other problems to take care of, as well),
> > here is the following:
> >
> >> These have all been discussed off an on over the past 5 years.
> >> I can't get at bugzilla right now, but all the details are logged in
> cases.
> >> A survey of all the distros, their kernel package, etc, were all looked
> at.
> >> We had to balance the traditional packaging with some new concepts
> >> and landed with what we have now.
> >
> > I tried several tests. This is my final conclusion (two cases):
> >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
> >
> > The kernel issue is described here: there is need to have the YOCTO
> > minimum configuration with the kernel setup:
> > [1] The entire kernel source code in:
> > /usr/src/kernel/`uname-r`/<kernel source code>
> > [2] The header files in: /usr/src/kernel/`uname-r`/<header file
> > directory structures>
> >
> > Point [1] is achieved with the following local.config file:
> >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
> >
> > Namely, with the following snippets in the local.conf:
> > TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
> > packagegroup-core-buildessential kernel-devsrc"
> > KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
> > packagegroup-core-buildessential kernel-devsrc"
> > KERNEL_DEV_MODULE = "kernel-modules"
> > CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
> > ${KERNEL_DEV_TOOLS} \
> > systemtap \
> > "
> >
> > Problem with this approach is that such a kernel makes the rootfs too
> > big and impractical:
> > -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
> > core-image-minimal-beaglebone.rootfs.tar.xz
> >
> > The main issue is point [2]: how to achieve it?
> > The suggestion is to introduce the new package in YOCTO kernel,
> > called: kernel-headers
> > The OBVIOUS benefit is that it will serve to the purpose of building
> > modules out of the tree on the target with
> > minimal mpact to rootfs!
>
> I think this is a fair suggestion. Having prebuilt kernel available
> that contains the configuration and header files used in the build is
> all that is required for external modules to build in addition to
> toolchain, so maybe its worth a try to create such a package and then
> have kernel-source separated out which can be installed on top if one
> needs
>
> >
> > Thank you,
> > Zoran Stojsavljevic
> > _______
> >
> > On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
> > <bruce.ashfield@gmail.com> wrote:
> >>
> >>
> >>
> >> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >>>
> >>>> The core-image-kernel-dev image is how I do all my on target
> >>>> testing when I introduce a new reference kernel for a release.
> >>>
> >>> Maybe you are correct. Maybe I should use/add in my local.conf the
> following:
> >>>
> >>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
> >>> packagegroup-core-buildessential kernel-devsrc"
> >>> KERNEL_DEV_MODULE ?= "kernel-modules"
> >>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
> >>>                               ${KERNEL_DEV_TOOLS} \
> >>>                               systemtap \
> >>>                              "
> >>> I need to try these... Maybe this addendum will solve the $1 mio USD
> problem?!
> >>>
> >>>> And IIRC the autobuilders are using a sato based image (Richard
> >>>> could confirm more easily that I could what image type the
> >>>> autobuilders are using for hello-world on target module tests).
> >>>
> >>> I am just advertising something more simple. To have mandatory
> >>> /lib/modules/`uname -r` directory. And introduce few more packages, as
> >>> Fedora distro, for example, has: kernel-headers (assuming YOCTO
> >>> rootfs, the following will be installed: /usr/src/kernel/`uname
> >>> -r`/<header file directory structures>. This also makes addition of
> >>> /lib/modules/`uname -r`/build file (which is soft link to
> >>> usr/src/kernel/`uname -r`).
> >>
> >>
> >> These have all been discussed off an on over the past 5 years. I can't
> get at bugzilla right now, but all the details are logged in cases. A
> survey of all the distros, their kernel package, etc, were all looked at.
> We had to balance the traditional packaging with some new concepts and
> landed with what we have now.
> >>
> >>
> >>>
> >>> Or kernel-devel package. Then, the whole current kernel source code
> >>> will be introduced, and also support for it.
> >>
> >>
> >> There's a case for this one as well, I'll probably have it done for the
> fall release. But our devsrc used to pretty much be the full source it has
> now been pruned down to something more manageable.  There are definitely
> some cases for having the full source on the target again, and it will be a
> separate package, just not the minimal one to build out of tree modules,
> etc.
> >>
> >>
> >>
> >>>
> >>>
> >>> SDK building with such a support is good/cool. But sometimes, before
> >>> introducing SDK, some tests should be done on target. NO need to
> >>> optionally include built-in layer hello-world driver example. Since I
> >>> (or you name the person) have own test drivers, which will be imported
> >>> out of tree, externally, to the target test bed!
> >>>
> >>
> >> I never use the SDK myself, so you are not alone in not going to it
> first. Hopefully I'll get some new patches out in the coming month before
> summer holidays really kick in.
> >>
> >> Bruce
> >>
> >>
> >>>
> >>> Just thinking loud...
> >>>
> >>> Zoran
> >>> _______
> >>>
> >>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield <
> bruce.ashfield@gmail.com> wrote:
> >>>>
> >>>>
> >>>>
> >>>> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >>>>>
> >>>>>> That's correct. That command only adds the kernel source and
> >>>>>> build infrastructure to the SDK, not to your target image. You'd
> still
> >>>>>> need to arrange to have the kernel-devsrc package installed on the
> >>>>>> target image if you want it on the board's rootfs. How you arrange
> >>>>>> to have the package installed to the image varies with the image
> >>>>>> (since they all don't have the same image install variables, etc).
> >>>>>
> >>>>> And here is a $1,000,000 USD question? How to do it on Poky (as
> >>>>> example of what you have stated in RED)? ;-)
> >>>>>
> >>>>> In other words: how to arrange it on Poky (as a Referent example)?
> >>>>
> >>>>
> >>>> The core-image-kernel-dev image is how I do all my on target testing
> when I introduce a new reference kernel for a release. And IIRC the
> autobuilders are using a sato based image (Richard could confirm more
> easily that I could what image type the autobuilders are using for
> hello-world on target module tests).
> >>>>
> >>>> Bruce
> >>>>
> >>>>
> >>>>>
> >>>>>
> >>>>> Thank you,
> >>>>> Zoran
> >>>>> _______
> >>>>>
> >>>>>
> >>>>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <
> bruce.ashfield@gmail.com> wrote:
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >>>>>>>
> >>>>>>> Hello Chris, Bruce,
> >>>>>>>
> >>>>>>> I have some additional data to share with you both, since I have
> tried
> >>>>>>> something. And here is my take on the things!
> >>>>>>>
> >>>>>>>> 1. Build using a bb recipe.
> >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for an
> example.
> >>>>>>>> You just need to add meta-skeleton to your bblayers.conf and then
> >>>>>>>>   bitbake hello-mod
> >>>>>>>
> >>>>>>> I looked into this example, and, yes, it is classic kernel module
> >>>>>>> definition out of the tree. With some outdated data, all cool, the
> >>>>>>> YOCTO designer should take care himself to fix these data, if using
> >>>>>>> this stuff.
> >>>>>>>
> >>>>>>> But this is NOT mandatory, since I can add out of the tree module
> NOT
> >>>>>>> actually using built-in module. I just use
> .../tmp/deploy/images/bbb/*
> >>>>>>> generated stuff, since I have automated scripts which are bringing
> all
> >>>>>>> these on my BBB target. Then I tftp my source code module to the
> >>>>>>> target.
> >>>>>>>
> >>>>>>>> 2. Build from the SDK:
> >>>>>>>> First, add the kernel source to the SDK by adding this to
> conf/local.conf
> >>>>>>>>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >>>>>>>
> >>>>>>> YES, this is THE command which should generate
> >>>>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
> >>>>>>> local.conf and after deleting kernel, then regenerating bitbake -k
> >>>>>>> core-image-minimal does not bring this path into the rootfs image!?
> >>>>>>
> >>>>>>
> >>>>>> That's correct. That command only adds the kernel source and build
> infrastructure to the SDK, not to your target image. You'd still need to
> arrange to have the kernel-devsrc package installed on the target image if
> you want it on the board's rootfs. How you arrange to have the package
> installed to the image varies with the image (since they all don't have the
> same image install variables, etc).
> >>>>>>
> >>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>> I did it actually using meta-bbb, and using poky referent distro as
> >>>>>>> two additional layers to the more complex bbb image!
> >>>>>>> https://github.com/jumpnow/meta-bbb.git
> >>>>>>>
> >>>>>>> The (KAS - you can figure out out of it local.conf) script I am
> using
> >>>>>>> to build such a BBB image is here:
> >>>>>>>
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
> >>>>>>>
> >>>>>>> I did not try it with BBB reference poky only! Maybe I should try
> it
> >>>>>>> as only referent poky? What do you think?
> >>>>>>>
> >>>>>>> Does in this case is SDK build really mandatory??? Should NOT be!
> >>>>>>>
> >>>>>>
> >>>>>> You only do the SDK steps if you want to support building out of
> tree modules in an SDK install. So it is not mandatory for on target module
> builds.
> >>>>>>
> >>>>>> Bruce
> >>>>>>
> >>>>>>
> >>>>>>>
> >>>>>>>> Once the SDK is installed, generate the kernel headers:
> >>>>>>>>   sudo -i
> >>>>>>>>   .
> /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >>>>>>>>   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >>>>>>>>   cd /usr/src/kernel
> >>>>>>>>   make oldconfig scripts
> >>>>>>>>   exit
> >>>>>>>
> >>>>>>> This is in nutshell the same what I did (a bit different) for
> Embedded
> >>>>>>> Debian. This is already on the target BBB, NOT while building YOCTO
> >>>>>>> BBB image!
> >>>>>>>
> >>>>>>>> Finally, build your module using a Makefile like this
> >>>>>>>>   obj-m := hello-mod.o
> >>>>>>>>   all:
> >>>>>>>>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
> >>>>>>>
> >>>>>>> As said before: bringing my own module into the target BBB (I have
> my
> >>>>>>> own examples, and I build them on the target with the almost the
> same
> >>>>>>> Makefiles)
> >>>>>>>
> >>>>>>> Zoran
> >>>>>>> _______
> >>>>>>>
> >>>>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk>
> wrote:
> >>>>>>>>
> >>>>>>>> Hi Zoran,
> >>>>>>>>
> >>>>>>>> There are two ways to do this
> >>>>>>>>
> >>>>>>>> 1. Build using a bb recipe.
> >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for an
> example.
> >>>>>>>> You just need to add meta-skeleton to your bblaysers.conf and then
> >>>>>>>>    bitbake hello-mod
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> 2. Build from the SDK:
> >>>>>>>> First, add the kernel source to the SDK by adding this to
> conf/local/conf
> >>>>>>>>    TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >>>>>>>>
> >>>>>>>> Then build the SDK
> >>>>>>>>    bitbake -c populate_sdk [your image recipe]
> >>>>>>>>
> >>>>>>>> Once the SDK is installed, generate the kernel headers:
> >>>>>>>>    sudo -i
> >>>>>>>>    .
> /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >>>>>>>>    cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >>>>>>>>    cd /usr/src/kernel
> >>>>>>>>    make oldconfig scripts
> >>>>>>>>    exit
> >>>>>>>>
> >>>>>>>> Finally, build your module using a Makefile like this
> >>>>>>>>
> >>>>>>>>    obj-m := hello-mod.o
> >>>>>>>>    all:
> >>>>>>>>          make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> HTH,
> >>>>>>>> Chris
> >>>>>>>>
> >>>>>>>> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
> >>>>>>>>> Hello to the YOCTO community,
> >>>>>>>>>
> >>>>>>>>> I am using (to build the target for Beagle Bone Black) the
> following script:
> >>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto
> >>>>>>>>>
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
> >>>>>>>>>
> >>>>>>>>> The latest kernel I am using from the following repo:
> >>>>>>>>> https://github.com/jumpnow/meta-bbb
> >>>>>>>>>
> >>>>>>>>> Is kernel 5.0.14 .
> >>>>>>>>>
> >>>>>>>>> Here is the snippet of the boot traces:
> >>>>>>>>> Starting kernel ...
> >>>>>>>>>
> >>>>>>>>> [    0.000000] Booting Linux on physical CPU 0x0
> >>>>>>>>> [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host)
> (gcc
> >>>>>>>>> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> >>>>>>>>> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2
> (ARMv7), cr=10c5387d
> >>>>>>>>> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT
> aliasing
> >>>>>>>>> instruction cache
> >>>>>>>>> [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
> >>>>>>>>> [    0.000000] Memory policy: Data cache writeback
> >>>>>>>>> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> >>>>>>>>> [    0.000000] CPU: All CPU(s) started in SVC mode.
> >>>>>>>>> [    0.000000] AM335X ES2.1 (sgx neon)
> >>>>>>>>> [    0.000000] random: get_random_bytes called from
> >>>>>>>>> start_kernel+0xa4/0x460 with crng_init=0
> >>>>>>>>> [    0.000000] Built 1 zonelists, mobility grouping on.  Total
> pages: 130048
> >>>>>>>>> [    0.000000] Kernel command line: console=ttyO0,115200n8
> >>>>>>>>> root=/dev/ram0 ip=dhcp
> >>>>>>>>>
> >>>>>>>>> According to the documentation, the following:
> >>>>>>>>> 2.10.1. Building Out-of-Tree Modules on the Target
> >>>>>>>>>
> https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
> >>>>>>>>>
> >>>>>>>>> I tried to find /usr/src/kernels/5.0.14... Directory, since I
> see
> >>>>>>>>> from the build that kernel-dev and kernel-devsrc are included:
> >>>>>>>>> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> >>>>>>>>> core-image-kernel-dev                                 :1.0-r0
> >>>>>>>>> kernel-devsrc                                         :1.0-r0
> >>>>>>>>> kernel-selftest                                       :1.0-r0
> >>>>>>>>>
> >>>>>>>>> THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
> >>>>>>>>> directory at all!?
> >>>>>>>>>
> >>>>>>>>> Two questions here?
> >>>>>>>>> [1] Do you have any advice on this problem (what I am missing
> here)?
> >>>>>>>>> [2] Alternative to [1]: how I can use cross compiler from
> >>>>>>>>> .../build/tmp to build Out-of-Tree Module for the BBB target on
> the
> >>>>>>>>> host?
> >>>>>>>>>
> >>>>>>>>> Thank you,
> >>>>>>>>> Zoran
> >>>>>>>>> _______
> >>>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> --
> >>>>>>>> Chris Simmonds, trainer and consultant at 2net
> >>>>>>>> http://www.2net.co.uk
> >>>>>>>> Author of "Mastering Embedded Linux Programming"
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> --
> >>>>>> - Thou shalt not follow the NULL pointer, for chaos and madness
> await thee at its end
> >>>>>> - "Use the force Harry" - Gandalf, Star Trek II
> >>>>>>
> >>>>
> >>>>
> >>>> --
> >>>> - Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end
> >>>> - "Use the force Harry" - Gandalf, Star Trek II
> >>>>
> >>
> >>
> >>
> >> --
> >> - Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end
> >> - "Use the force Harry" - Gandalf, Star Trek II
> >>
>

[-- Attachment #2: Type: text/html, Size: 26646 bytes --]

Re: Building Out-of-Tree Modules on the BBB Target

[Khem Raj]

On 5/23/19 9:14 PM, Zoran Stojsavljevic wrote:
>  > I think this is a fair suggestion. Having prebuilt kernel available
>  > that contains the configuration and header files used in the build is
>  > all that is required for external modules to build in addition to
>  > toolchain, so maybe its worth a try to create such a package and then
>  > have kernel-source separated out which can be installed on top if one
>  > needs
> 
> I am man of experimental try-outs. So, in order to see how big kernel is,
> I did the following:
> Fedora 29 (which I am using as a host) with kernel-headers (NOT full
> kernel source tree):
> [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ pwd
> /usr/src/kernels/5.0.16-200.fc29.x86_64
> [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ du --summarize
> /*102124    . <<======= ~95MB*/
> 
> Kernel.org kernel 5.0.6, the full kernel source tree size:
> [vuser@fedora29-ssd linux-5.0.6]$ pwd
> /home/vuser/projects/kernel.org/linux-5.0.6 <http://kernel.org/linux-5.0.6>
> [vuser@fedora29-ssd linux-5.0.6]$ du --summarize
> /*960592    . <<======= ~900MB*/
> 
> These are ballpark numbers. You can draw conclusions for yourselves!
> 
> It is ~ 7x to 9x reduction in size. Having BBB's DDR2 of size 512MB,
> and initramfs for testing purposes, in speaks for itself.
> 

yes thats what I was expecting too. Anything smaller helps.


> (I am aware that YOCTO kernels are less/smaller in size, but how smaller?)
> 

Not in source. The binaries may be

> Zoran
> _______
> 
> 
> On Fri, May 24, 2019 at 3:00 AM Khem Raj <raj.khem@gmail.com 
> <mailto:raj.khem@gmail.com>> wrote:
> 
> 
> 
>     On 5/23/19 3:32 AM, Zoran Stojsavljevic wrote:
>      > After some tests (and I had other problems to take care of, as well),
>      > here is the following:
>      >
>      >> These have all been discussed off an on over the past 5 years.
>      >> I can't get at bugzilla right now, but all the details are
>     logged in cases.
>      >> A survey of all the distros, their kernel package, etc, were all
>     looked at.
>      >> We had to balance the traditional packaging with some new concepts
>      >> and landed with what we have now.
>      >
>      > I tried several tests. This is my final conclusion (two cases):
>      >
>     https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
>      >
>      > The kernel issue is described here: there is need to have the YOCTO
>      > minimum configuration with the kernel setup:
>      > [1] The entire kernel source code in:
>      > /usr/src/kernel/`uname-r`/<kernel source code>
>      > [2] The header files in: /usr/src/kernel/`uname-r`/<header file
>      > directory structures>
>      >
>      > Point [1] is achieved with the following local.config file:
>      >
>     https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
>      >
>      > Namely, with the following snippets in the local.conf:
>      > TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
>      > packagegroup-core-buildessential kernel-devsrc"
>      > KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
>      > packagegroup-core-buildessential kernel-devsrc"
>      > KERNEL_DEV_MODULE = "kernel-modules"
>      > CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>      > ${KERNEL_DEV_TOOLS} \
>      > systemtap \
>      > "
>      >
>      > Problem with this approach is that such a kernel makes the rootfs too
>      > big and impractical:
>      > -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
>      > core-image-minimal-beaglebone.rootfs.tar.xz
>      >
>      > The main issue is point [2]: how to achieve it?
>      > The suggestion is to introduce the new package in YOCTO kernel,
>      > called: kernel-headers
>      > The OBVIOUS benefit is that it will serve to the purpose of building
>      > modules out of the tree on the target with
>      > minimal mpact to rootfs!
> 
>     I think this is a fair suggestion. Having prebuilt kernel available
>     that contains the configuration and header files used in the build is
>     all that is required for external modules to build in addition to
>     toolchain, so maybe its worth a try to create such a package and then
>     have kernel-source separated out which can be installed on top if one
>     needs
> 
>      >
>      > Thank you,
>      > Zoran Stojsavljevic
>      > _______
>      >
>      > On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
>      > <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
>      >>
>      >>
>      >>
>      >> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic
>     <zoran.stojsavljevic@gmail.com
>     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>      >>>
>      >>>> The core-image-kernel-dev image is how I do all my on target
>      >>>> testing when I introduce a new reference kernel for a release.
>      >>>
>      >>> Maybe you are correct. Maybe I should use/add in my local.conf
>     the following:
>      >>>
>      >>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
>      >>> packagegroup-core-buildessential kernel-devsrc"
>      >>> KERNEL_DEV_MODULE ?= "kernel-modules"
>      >>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>      >>>                               ${KERNEL_DEV_TOOLS} \
>      >>>                               systemtap \
>      >>>                              "
>      >>> I need to try these... Maybe this addendum will solve the $1
>     mio USD problem?!
>      >>>
>      >>>> And IIRC the autobuilders are using a sato based image (Richard
>      >>>> could confirm more easily that I could what image type the
>      >>>> autobuilders are using for hello-world on target module tests).
>      >>>
>      >>> I am just advertising something more simple. To have mandatory
>      >>> /lib/modules/`uname -r` directory. And introduce few more
>     packages, as
>      >>> Fedora distro, for example, has: kernel-headers (assuming YOCTO
>      >>> rootfs, the following will be installed: /usr/src/kernel/`uname
>      >>> -r`/<header file directory structures>. This also makes addition of
>      >>> /lib/modules/`uname -r`/build file (which is soft link to
>      >>> usr/src/kernel/`uname -r`).
>      >>
>      >>
>      >> These have all been discussed off an on over the past 5 years. I
>     can't get at bugzilla right now, but all the details are logged in
>     cases. A survey of all the distros, their kernel package, etc, were
>     all looked at. We had to balance the traditional packaging with some
>     new concepts and landed with what we have now.
>      >>
>      >>
>      >>>
>      >>> Or kernel-devel package. Then, the whole current kernel source code
>      >>> will be introduced, and also support for it.
>      >>
>      >>
>      >> There's a case for this one as well, I'll probably have it done
>     for the fall release. But our devsrc used to pretty much be the full
>     source it has now been pruned down to something more manageable. 
>     There are definitely some cases for having the full source on the
>     target again, and it will be a separate package, just not the
>     minimal one to build out of tree modules, etc.
>      >>
>      >>
>      >>
>      >>>
>      >>>
>      >>> SDK building with such a support is good/cool. But sometimes,
>     before
>      >>> introducing SDK, some tests should be done on target. NO need to
>      >>> optionally include built-in layer hello-world driver example.
>     Since I
>      >>> (or you name the person) have own test drivers, which will be
>     imported
>      >>> out of tree, externally, to the target test bed!
>      >>>
>      >>
>      >> I never use the SDK myself, so you are not alone in not going to
>     it first. Hopefully I'll get some new patches out in the coming
>     month before summer holidays really kick in.
>      >>
>      >> Bruce
>      >>
>      >>
>      >>>
>      >>> Just thinking loud...
>      >>>
>      >>> Zoran
>      >>> _______
>      >>>
>      >>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield
>     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
>      >>>>
>      >>>>
>      >>>>
>      >>>> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic
>     <zoran.stojsavljevic@gmail.com
>     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>      >>>>>
>      >>>>>> That's correct. That command only adds the kernel source and
>      >>>>>> build infrastructure to the SDK, not to your target image.
>     You'd still
>      >>>>>> need to arrange to have the kernel-devsrc package installed
>     on the
>      >>>>>> target image if you want it on the board's rootfs. How you
>     arrange
>      >>>>>> to have the package installed to the image varies with the image
>      >>>>>> (since they all don't have the same image install variables,
>     etc).
>      >>>>>
>      >>>>> And here is a $1,000,000 USD question? How to do it on Poky (as
>      >>>>> example of what you have stated in RED)? ;-)
>      >>>>>
>      >>>>> In other words: how to arrange it on Poky (as a Referent
>     example)?
>      >>>>
>      >>>>
>      >>>> The core-image-kernel-dev image is how I do all my on target
>     testing when I introduce a new reference kernel for a release. And
>     IIRC the autobuilders are using a sato based image (Richard could
>     confirm more easily that I could what image type the autobuilders
>     are using for hello-world on target module tests).
>      >>>>
>      >>>> Bruce
>      >>>>
>      >>>>
>      >>>>>
>      >>>>>
>      >>>>> Thank you,
>      >>>>> Zoran
>      >>>>> _______
>      >>>>>
>      >>>>>
>      >>>>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield
>     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
>      >>>>>>
>      >>>>>>
>      >>>>>>
>      >>>>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic
>     <zoran.stojsavljevic@gmail.com
>     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>      >>>>>>>
>      >>>>>>> Hello Chris, Bruce,
>      >>>>>>>
>      >>>>>>> I have some additional data to share with you both, since I
>     have tried
>      >>>>>>> something. And here is my take on the things!
>      >>>>>>>
>      >>>>>>>> 1. Build using a bb recipe.
>      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
>     an example.
>      >>>>>>>> You just need to add meta-skeleton to your bblayers.conf
>     and then
>      >>>>>>>>   bitbake hello-mod
>      >>>>>>>
>      >>>>>>> I looked into this example, and, yes, it is classic kernel
>     module
>      >>>>>>> definition out of the tree. With some outdated data, all
>     cool, the
>      >>>>>>> YOCTO designer should take care himself to fix these data,
>     if using
>      >>>>>>> this stuff.
>      >>>>>>>
>      >>>>>>> But this is NOT mandatory, since I can add out of the tree
>     module NOT
>      >>>>>>> actually using built-in module. I just use
>     .../tmp/deploy/images/bbb/*
>      >>>>>>> generated stuff, since I have automated scripts which are
>     bringing all
>      >>>>>>> these on my BBB target. Then I tftp my source code module
>     to the
>      >>>>>>> target.
>      >>>>>>>
>      >>>>>>>> 2. Build from the SDK:
>      >>>>>>>> First, add the kernel source to the SDK by adding this to
>     conf/local.conf
>      >>>>>>>>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>      >>>>>>>
>      >>>>>>> YES, this is THE command which should generate
>      >>>>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
>      >>>>>>> local.conf and after deleting kernel, then regenerating
>     bitbake -k
>      >>>>>>> core-image-minimal does not bring this path into the rootfs
>     image!?
>      >>>>>>
>      >>>>>>
>      >>>>>> That's correct. That command only adds the kernel source and
>     build infrastructure to the SDK, not to your target image. You'd
>     still need to arrange to have the kernel-devsrc package installed on
>     the target image if you want it on the board's rootfs. How you
>     arrange to have the package installed to the image varies with the
>     image (since they all don't have the same image install variables, etc).
>      >>>>>>
>      >>>>>>
>      >>>>>>>
>      >>>>>>>
>      >>>>>>> I did it actually using meta-bbb, and using poky referent
>     distro as
>      >>>>>>> two additional layers to the more complex bbb image!
>      >>>>>>> https://github.com/jumpnow/meta-bbb.git
>      >>>>>>>
>      >>>>>>> The (KAS - you can figure out out of it local.conf) script
>     I am using
>      >>>>>>> to build such a BBB image is here:
>      >>>>>>>
>     https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>      >>>>>>>
>      >>>>>>> I did not try it with BBB reference poky only! Maybe I
>     should try it
>      >>>>>>> as only referent poky? What do you think?
>      >>>>>>>
>      >>>>>>> Does in this case is SDK build really mandatory??? Should
>     NOT be!
>      >>>>>>>
>      >>>>>>
>      >>>>>> You only do the SDK steps if you want to support building
>     out of tree modules in an SDK install. So it is not mandatory for on
>     target module builds.
>      >>>>>>
>      >>>>>> Bruce
>      >>>>>>
>      >>>>>>
>      >>>>>>>
>      >>>>>>>> Once the SDK is installed, generate the kernel headers:
>      >>>>>>>>   sudo -i
>      >>>>>>>>   .
>     /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>      >>>>>>>>   cd
>     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>      >>>>>>>>   cd /usr/src/kernel
>      >>>>>>>>   make oldconfig scripts
>      >>>>>>>>   exit
>      >>>>>>>
>      >>>>>>> This is in nutshell the same what I did (a bit different)
>     for Embedded
>      >>>>>>> Debian. This is already on the target BBB, NOT while
>     building YOCTO
>      >>>>>>> BBB image!
>      >>>>>>>
>      >>>>>>>> Finally, build your module using a Makefile like this
>      >>>>>>>>   obj-m := hello-mod.o
>      >>>>>>>>   all:
>      >>>>>>>>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel
>     M=$(shell pwd)
>      >>>>>>>
>      >>>>>>> As said before: bringing my own module into the target BBB
>     (I have my
>      >>>>>>> own examples, and I build them on the target with the
>     almost the same
>      >>>>>>> Makefiles)
>      >>>>>>>
>      >>>>>>> Zoran
>      >>>>>>> _______
>      >>>>>>>
>      >>>>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds
>     <chris@2net.co.uk <mailto:chris@2net.co.uk>> wrote:
>      >>>>>>>>
>      >>>>>>>> Hi Zoran,
>      >>>>>>>>
>      >>>>>>>> There are two ways to do this
>      >>>>>>>>
>      >>>>>>>> 1. Build using a bb recipe.
>      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
>     an example.
>      >>>>>>>> You just need to add meta-skeleton to your bblaysers.conf
>     and then
>      >>>>>>>>    bitbake hello-mod
>      >>>>>>>>
>      >>>>>>>>
>      >>>>>>>> 2. Build from the SDK:
>      >>>>>>>> First, add the kernel source to the SDK by adding this to
>     conf/local/conf
>      >>>>>>>>    TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>      >>>>>>>>
>      >>>>>>>> Then build the SDK
>      >>>>>>>>    bitbake -c populate_sdk [your image recipe]
>      >>>>>>>>
>      >>>>>>>> Once the SDK is installed, generate the kernel headers:
>      >>>>>>>>    sudo -i
>      >>>>>>>>    .
>     /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>      >>>>>>>>    cd
>     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>      >>>>>>>>    cd /usr/src/kernel
>      >>>>>>>>    make oldconfig scripts
>      >>>>>>>>    exit
>      >>>>>>>>
>      >>>>>>>> Finally, build your module using a Makefile like this
>      >>>>>>>>
>      >>>>>>>>    obj-m := hello-mod.o
>      >>>>>>>>    all:
>      >>>>>>>>          make -C $(SDKTARGETSYSROOT)/usr/src/kernel
>     M=$(shell pwd)
>      >>>>>>>>
>      >>>>>>>>
>      >>>>>>>> HTH,
>      >>>>>>>> Chris
>      >>>>>>>>
>      >>>>>>>> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>      >>>>>>>>> Hello to the YOCTO community,
>      >>>>>>>>>
>      >>>>>>>>> I am using (to build the target for Beagle Bone Black)
>     the following script:
>      >>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto
>      >>>>>>>>>
>     https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>      >>>>>>>>>
>      >>>>>>>>> The latest kernel I am using from the following repo:
>      >>>>>>>>> https://github.com/jumpnow/meta-bbb
>      >>>>>>>>>
>      >>>>>>>>> Is kernel 5.0.14 .
>      >>>>>>>>>
>      >>>>>>>>> Here is the snippet of the boot traces:
>      >>>>>>>>> Starting kernel ...
>      >>>>>>>>>
>      >>>>>>>>> [    0.000000] Booting Linux on physical CPU 0x0
>      >>>>>>>>> [    0.000000] Linux version 5.0.14-jumpnow
>     (oe-user@oe-host) (gcc
>      >>>>>>>>> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>      >>>>>>>>> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2
>     (ARMv7), cr=10c5387d
>      >>>>>>>>> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache,
>     VIPT aliasing
>      >>>>>>>>> instruction cache
>      >>>>>>>>> [    0.000000] OF: fdt: Machine model: TI AM335x
>     BeagleBone Black
>      >>>>>>>>> [    0.000000] Memory policy: Data cache writeback
>      >>>>>>>>> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>      >>>>>>>>> [    0.000000] CPU: All CPU(s) started in SVC mode.
>      >>>>>>>>> [    0.000000] AM335X ES2.1 (sgx neon)
>      >>>>>>>>> [    0.000000] random: get_random_bytes called from
>      >>>>>>>>> start_kernel+0xa4/0x460 with crng_init=0
>      >>>>>>>>> [    0.000000] Built 1 zonelists, mobility grouping on. 
>     Total pages: 130048
>      >>>>>>>>> [    0.000000] Kernel command line: console=ttyO0,115200n8
>      >>>>>>>>> root=/dev/ram0 ip=dhcp
>      >>>>>>>>>
>      >>>>>>>>> According to the documentation, the following:
>      >>>>>>>>> 2.10.1. Building Out-of-Tree Modules on the Target
>      >>>>>>>>>
>     https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>      >>>>>>>>>
>      >>>>>>>>> I tried to find /usr/src/kernels/5.0.14.
>     <http://5.0.14.>.. Directory, since I see
>      >>>>>>>>> from the build that kernel-dev and kernel-devsrc are
>     included:
>      >>>>>>>>> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>      >>>>>>>>> core-image-kernel-dev                                 :1.0-r0
>      >>>>>>>>> kernel-devsrc                                         :1.0-r0
>      >>>>>>>>> kernel-selftest                                       :1.0-r0
>      >>>>>>>>>
>      >>>>>>>>> THE PROBLEM: But I could not find ob BBB target
>     /usr/src/kernels
>      >>>>>>>>> directory at all!?
>      >>>>>>>>>
>      >>>>>>>>> Two questions here?
>      >>>>>>>>> [1] Do you have any advice on this problem (what I am
>     missing here)?
>      >>>>>>>>> [2] Alternative to [1]: how I can use cross compiler from
>      >>>>>>>>> .../build/tmp to build Out-of-Tree Module for the BBB
>     target on the
>      >>>>>>>>> host?
>      >>>>>>>>>
>      >>>>>>>>> Thank you,
>      >>>>>>>>> Zoran
>      >>>>>>>>> _______
>      >>>>>>>>>
>      >>>>>>>>
>      >>>>>>>>
>      >>>>>>>> --
>      >>>>>>>> Chris Simmonds, trainer and consultant at 2net
>      >>>>>>>> http://www.2net.co.uk
>      >>>>>>>> Author of "Mastering Embedded Linux Programming"
>      >>>>>>
>      >>>>>>
>      >>>>>>
>      >>>>>> --
>      >>>>>> - Thou shalt not follow the NULL pointer, for chaos and
>     madness await thee at its end
>      >>>>>> - "Use the force Harry" - Gandalf, Star Trek II
>      >>>>>>
>      >>>>
>      >>>>
>      >>>> --
>      >>>> - Thou shalt not follow the NULL pointer, for chaos and
>     madness await thee at its end
>      >>>> - "Use the force Harry" - Gandalf, Star Trek II
>      >>>>
>      >>
>      >>
>      >>
>      >> --
>      >> - Thou shalt not follow the NULL pointer, for chaos and madness
>     await thee at its end
>      >> - "Use the force Harry" - Gandalf, Star Trek II
>      >>
> 

Re: Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

[-- Attachment #1: Type: text/plain, Size: 23537 bytes --]

As I said, I am a man of experimental try-outs. And here is the try!

Now, after setting sources, I tried to compile the example (from my Git):
https://github.com/ZoranStojsavljevic/bbb-yocto/tree/master/Issues/LKM

The results are the following (all on the target):
root@beaglebone:~# pwd
/home/root
root@beaglebone:~# ls -al
drwx------    2 root     root             0 May 24 13:11 .
drwxr-xr-x    3 root     root             0 May 23 13:03 ..
-rw-r--r--    1 root     root           159 May 24 12:54 Makefile
-rw-r--r--    1 root     root          1228 May 24 12:54 p15_test.c
root@beaglebone:~# make all
make -C /lib/modules/5.0.15-jumpnow/build M=/home/root modules
make[1]: Entering directory '/lib/modules/5.0.15-jumpnow/build'
  CC [M]  /home/root/p15_test.o
In file included from ./include/asm-generic/int-ll64.h:11,
                 from ./arch/arm/include/uapi/asm/types.h:5,
                 from ./include/uapi/linux/types.h:5,
                 from ./include/linux/types.h:6,
                 from ./include/linux/list.h:5,
                 from ./include/linux/module.h:9,
                 from /home/root/p15_test.c:5:
*./include/uapi/asm-generic/int-ll64.h:12:10: fatal error:
asm/bitsperlong.h: No such file or directory*
 #include <asm/bitsperlong.h>
          ^~~~~~~~~~~~~~~~~~~
compilation terminated.



*make[2]: *** [scripts/Makefile.build:283: /home/root/p15_test.o] Error
1make[1]: *** [Makefile:1577: _module_/home/root] Error 2make[1]: Leaving
directory '/lib/modules/5.0.15-jumpnow/build'make: *** [Makefile:4: all]
Error 2*

I see that you have changed the kernel from 5.0.7-jumpnow to 5.0.15-jumpnow
. Did you?

This example works on the same target out of Debian (flashed in eMMC),
without the problems.

Something is wrong with the YOCTO source kernel tree.

You are free to try example on YOCTO and Embedded Debian yourselves!

Zoran
_______

On Fri, May 24, 2019 at 6:37 AM Khem Raj <raj.khem@gmail.com> wrote:

>
>
> On 5/23/19 9:14 PM, Zoran Stojsavljevic wrote:
> >  > I think this is a fair suggestion. Having prebuilt kernel available
> >  > that contains the configuration and header files used in the build is
> >  > all that is required for external modules to build in addition to
> >  > toolchain, so maybe its worth a try to create such a package and then
> >  > have kernel-source separated out which can be installed on top if one
> >  > needs
> >
> > I am man of experimental try-outs. So, in order to see how big kernel is,
> > I did the following:
> > Fedora 29 (which I am using as a host) with kernel-headers (NOT full
> > kernel source tree):
> > [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ pwd
> > /usr/src/kernels/5.0.16-200.fc29.x86_64
> > [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ du --summarize
> > /*102124    . <<======= ~95MB*/
> >
> > Kernel.org kernel 5.0.6, the full kernel source tree size:
> > [vuser@fedora29-ssd linux-5.0.6]$ pwd
> > /home/vuser/projects/kernel.org/linux-5.0.6 <
> http://kernel.org/linux-5.0.6>
> > [vuser@fedora29-ssd linux-5.0.6]$ du --summarize
> > /*960592    . <<======= ~900MB*/
> >
> > These are ballpark numbers. You can draw conclusions for yourselves!
> >
> > It is ~ 7x to 9x reduction in size. Having BBB's DDR2 of size 512MB,
> > and initramfs for testing purposes, in speaks for itself.
> >
>
> yes thats what I was expecting too. Anything smaller helps.
>
>
> > (I am aware that YOCTO kernels are less/smaller in size, but how
> smaller?)
> >
>
> Not in source. The binaries may be
>
> > Zoran
> > _______
> >
> >
> > On Fri, May 24, 2019 at 3:00 AM Khem Raj <raj.khem@gmail.com
> > <mailto:raj.khem@gmail.com>> wrote:
> >
> >
> >
> >     On 5/23/19 3:32 AM, Zoran Stojsavljevic wrote:
> >      > After some tests (and I had other problems to take care of, as
> well),
> >      > here is the following:
> >      >
> >      >> These have all been discussed off an on over the past 5 years.
> >      >> I can't get at bugzilla right now, but all the details are
> >     logged in cases.
> >      >> A survey of all the distros, their kernel package, etc, were all
> >     looked at.
> >      >> We had to balance the traditional packaging with some new
> concepts
> >      >> and landed with what we have now.
> >      >
> >      > I tried several tests. This is my final conclusion (two cases):
> >      >
> >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
> >      >
> >      > The kernel issue is described here: there is need to have the
> YOCTO
> >      > minimum configuration with the kernel setup:
> >      > [1] The entire kernel source code in:
> >      > /usr/src/kernel/`uname-r`/<kernel source code>
> >      > [2] The header files in: /usr/src/kernel/`uname-r`/<header file
> >      > directory structures>
> >      >
> >      > Point [1] is achieved with the following local.config file:
> >      >
> >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
> >      >
> >      > Namely, with the following snippets in the local.conf:
> >      > TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
> >      > packagegroup-core-buildessential kernel-devsrc"
> >      > KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
> >      > packagegroup-core-buildessential kernel-devsrc"
> >      > KERNEL_DEV_MODULE = "kernel-modules"
> >      > CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
> >      > ${KERNEL_DEV_TOOLS} \
> >      > systemtap \
> >      > "
> >      >
> >      > Problem with this approach is that such a kernel makes the rootfs
> too
> >      > big and impractical:
> >      > -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
> >      > core-image-minimal-beaglebone.rootfs.tar.xz
> >      >
> >      > The main issue is point [2]: how to achieve it?
> >      > The suggestion is to introduce the new package in YOCTO kernel,
> >      > called: kernel-headers
> >      > The OBVIOUS benefit is that it will serve to the purpose of
> building
> >      > modules out of the tree on the target with
> >      > minimal mpact to rootfs!
> >
> >     I think this is a fair suggestion. Having prebuilt kernel available
> >     that contains the configuration and header files used in the build is
> >     all that is required for external modules to build in addition to
> >     toolchain, so maybe its worth a try to create such a package and then
> >     have kernel-source separated out which can be installed on top if one
> >     needs
> >
> >      >
> >      > Thank you,
> >      > Zoran Stojsavljevic
> >      > _______
> >      >
> >      > On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
> >      > <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>>
> wrote:
> >      >>
> >      >>
> >      >>
> >      >> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic
> >     <zoran.stojsavljevic@gmail.com
> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
> >      >>>
> >      >>>> The core-image-kernel-dev image is how I do all my on target
> >      >>>> testing when I introduce a new reference kernel for a release.
> >      >>>
> >      >>> Maybe you are correct. Maybe I should use/add in my local.conf
> >     the following:
> >      >>>
> >      >>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
> >      >>> packagegroup-core-buildessential kernel-devsrc"
> >      >>> KERNEL_DEV_MODULE ?= "kernel-modules"
> >      >>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
> >      >>>                               ${KERNEL_DEV_TOOLS} \
> >      >>>                               systemtap \
> >      >>>                              "
> >      >>> I need to try these... Maybe this addendum will solve the $1
> >     mio USD problem?!
> >      >>>
> >      >>>> And IIRC the autobuilders are using a sato based image (Richard
> >      >>>> could confirm more easily that I could what image type the
> >      >>>> autobuilders are using for hello-world on target module tests).
> >      >>>
> >      >>> I am just advertising something more simple. To have mandatory
> >      >>> /lib/modules/`uname -r` directory. And introduce few more
> >     packages, as
> >      >>> Fedora distro, for example, has: kernel-headers (assuming YOCTO
> >      >>> rootfs, the following will be installed: /usr/src/kernel/`uname
> >      >>> -r`/<header file directory structures>. This also makes
> addition of
> >      >>> /lib/modules/`uname -r`/build file (which is soft link to
> >      >>> usr/src/kernel/`uname -r`).
> >      >>
> >      >>
> >      >> These have all been discussed off an on over the past 5 years. I
> >     can't get at bugzilla right now, but all the details are logged in
> >     cases. A survey of all the distros, their kernel package, etc, were
> >     all looked at. We had to balance the traditional packaging with some
> >     new concepts and landed with what we have now.
> >      >>
> >      >>
> >      >>>
> >      >>> Or kernel-devel package. Then, the whole current kernel source
> code
> >      >>> will be introduced, and also support for it.
> >      >>
> >      >>
> >      >> There's a case for this one as well, I'll probably have it done
> >     for the fall release. But our devsrc used to pretty much be the full
> >     source it has now been pruned down to something more manageable.
> >     There are definitely some cases for having the full source on the
> >     target again, and it will be a separate package, just not the
> >     minimal one to build out of tree modules, etc.
> >      >>
> >      >>
> >      >>
> >      >>>
> >      >>>
> >      >>> SDK building with such a support is good/cool. But sometimes,
> >     before
> >      >>> introducing SDK, some tests should be done on target. NO need to
> >      >>> optionally include built-in layer hello-world driver example.
> >     Since I
> >      >>> (or you name the person) have own test drivers, which will be
> >     imported
> >      >>> out of tree, externally, to the target test bed!
> >      >>>
> >      >>
> >      >> I never use the SDK myself, so you are not alone in not going to
> >     it first. Hopefully I'll get some new patches out in the coming
> >     month before summer holidays really kick in.
> >      >>
> >      >> Bruce
> >      >>
> >      >>
> >      >>>
> >      >>> Just thinking loud...
> >      >>>
> >      >>> Zoran
> >      >>> _______
> >      >>>
> >      >>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield
> >     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
> >      >>>>
> >      >>>>
> >      >>>>
> >      >>>> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic
> >     <zoran.stojsavljevic@gmail.com
> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
> >      >>>>>
> >      >>>>>> That's correct. That command only adds the kernel source and
> >      >>>>>> build infrastructure to the SDK, not to your target image.
> >     You'd still
> >      >>>>>> need to arrange to have the kernel-devsrc package installed
> >     on the
> >      >>>>>> target image if you want it on the board's rootfs. How you
> >     arrange
> >      >>>>>> to have the package installed to the image varies with the
> image
> >      >>>>>> (since they all don't have the same image install variables,
> >     etc).
> >      >>>>>
> >      >>>>> And here is a $1,000,000 USD question? How to do it on Poky
> (as
> >      >>>>> example of what you have stated in RED)? ;-)
> >      >>>>>
> >      >>>>> In other words: how to arrange it on Poky (as a Referent
> >     example)?
> >      >>>>
> >      >>>>
> >      >>>> The core-image-kernel-dev image is how I do all my on target
> >     testing when I introduce a new reference kernel for a release. And
> >     IIRC the autobuilders are using a sato based image (Richard could
> >     confirm more easily that I could what image type the autobuilders
> >     are using for hello-world on target module tests).
> >      >>>>
> >      >>>> Bruce
> >      >>>>
> >      >>>>
> >      >>>>>
> >      >>>>>
> >      >>>>> Thank you,
> >      >>>>> Zoran
> >      >>>>> _______
> >      >>>>>
> >      >>>>>
> >      >>>>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield
> >     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
> >      >>>>>>
> >      >>>>>>
> >      >>>>>>
> >      >>>>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic
> >     <zoran.stojsavljevic@gmail.com
> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
> >      >>>>>>>
> >      >>>>>>> Hello Chris, Bruce,
> >      >>>>>>>
> >      >>>>>>> I have some additional data to share with you both, since I
> >     have tried
> >      >>>>>>> something. And here is my take on the things!
> >      >>>>>>>
> >      >>>>>>>> 1. Build using a bb recipe.
> >      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
> >     an example.
> >      >>>>>>>> You just need to add meta-skeleton to your bblayers.conf
> >     and then
> >      >>>>>>>>   bitbake hello-mod
> >      >>>>>>>
> >      >>>>>>> I looked into this example, and, yes, it is classic kernel
> >     module
> >      >>>>>>> definition out of the tree. With some outdated data, all
> >     cool, the
> >      >>>>>>> YOCTO designer should take care himself to fix these data,
> >     if using
> >      >>>>>>> this stuff.
> >      >>>>>>>
> >      >>>>>>> But this is NOT mandatory, since I can add out of the tree
> >     module NOT
> >      >>>>>>> actually using built-in module. I just use
> >     .../tmp/deploy/images/bbb/*
> >      >>>>>>> generated stuff, since I have automated scripts which are
> >     bringing all
> >      >>>>>>> these on my BBB target. Then I tftp my source code module
> >     to the
> >      >>>>>>> target.
> >      >>>>>>>
> >      >>>>>>>> 2. Build from the SDK:
> >      >>>>>>>> First, add the kernel source to the SDK by adding this to
> >     conf/local.conf
> >      >>>>>>>>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >      >>>>>>>
> >      >>>>>>> YES, this is THE command which should generate
> >      >>>>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
> >      >>>>>>> local.conf and after deleting kernel, then regenerating
> >     bitbake -k
> >      >>>>>>> core-image-minimal does not bring this path into the rootfs
> >     image!?
> >      >>>>>>
> >      >>>>>>
> >      >>>>>> That's correct. That command only adds the kernel source and
> >     build infrastructure to the SDK, not to your target image. You'd
> >     still need to arrange to have the kernel-devsrc package installed on
> >     the target image if you want it on the board's rootfs. How you
> >     arrange to have the package installed to the image varies with the
> >     image (since they all don't have the same image install variables,
> etc).
> >      >>>>>>
> >      >>>>>>
> >      >>>>>>>
> >      >>>>>>>
> >      >>>>>>> I did it actually using meta-bbb, and using poky referent
> >     distro as
> >      >>>>>>> two additional layers to the more complex bbb image!
> >      >>>>>>> https://github.com/jumpnow/meta-bbb.git
> >      >>>>>>>
> >      >>>>>>> The (KAS - you can figure out out of it local.conf) script
> >     I am using
> >      >>>>>>> to build such a BBB image is here:
> >      >>>>>>>
> >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
> >      >>>>>>>
> >      >>>>>>> I did not try it with BBB reference poky only! Maybe I
> >     should try it
> >      >>>>>>> as only referent poky? What do you think?
> >      >>>>>>>
> >      >>>>>>> Does in this case is SDK build really mandatory??? Should
> >     NOT be!
> >      >>>>>>>
> >      >>>>>>
> >      >>>>>> You only do the SDK steps if you want to support building
> >     out of tree modules in an SDK install. So it is not mandatory for on
> >     target module builds.
> >      >>>>>>
> >      >>>>>> Bruce
> >      >>>>>>
> >      >>>>>>
> >      >>>>>>>
> >      >>>>>>>> Once the SDK is installed, generate the kernel headers:
> >      >>>>>>>>   sudo -i
> >      >>>>>>>>   .
> >     /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >      >>>>>>>>   cd
> >     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >      >>>>>>>>   cd /usr/src/kernel
> >      >>>>>>>>   make oldconfig scripts
> >      >>>>>>>>   exit
> >      >>>>>>>
> >      >>>>>>> This is in nutshell the same what I did (a bit different)
> >     for Embedded
> >      >>>>>>> Debian. This is already on the target BBB, NOT while
> >     building YOCTO
> >      >>>>>>> BBB image!
> >      >>>>>>>
> >      >>>>>>>> Finally, build your module using a Makefile like this
> >      >>>>>>>>   obj-m := hello-mod.o
> >      >>>>>>>>   all:
> >      >>>>>>>>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel
> >     M=$(shell pwd)
> >      >>>>>>>
> >      >>>>>>> As said before: bringing my own module into the target BBB
> >     (I have my
> >      >>>>>>> own examples, and I build them on the target with the
> >     almost the same
> >      >>>>>>> Makefiles)
> >      >>>>>>>
> >      >>>>>>> Zoran
> >      >>>>>>> _______
> >      >>>>>>>
> >      >>>>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds
> >     <chris@2net.co.uk <mailto:chris@2net.co.uk>> wrote:
> >      >>>>>>>>
> >      >>>>>>>> Hi Zoran,
> >      >>>>>>>>
> >      >>>>>>>> There are two ways to do this
> >      >>>>>>>>
> >      >>>>>>>> 1. Build using a bb recipe.
> >      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
> >     an example.
> >      >>>>>>>> You just need to add meta-skeleton to your bblaysers.conf
> >     and then
> >      >>>>>>>>    bitbake hello-mod
> >      >>>>>>>>
> >      >>>>>>>>
> >      >>>>>>>> 2. Build from the SDK:
> >      >>>>>>>> First, add the kernel source to the SDK by adding this to
> >     conf/local/conf
> >      >>>>>>>>    TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >      >>>>>>>>
> >      >>>>>>>> Then build the SDK
> >      >>>>>>>>    bitbake -c populate_sdk [your image recipe]
> >      >>>>>>>>
> >      >>>>>>>> Once the SDK is installed, generate the kernel headers:
> >      >>>>>>>>    sudo -i
> >      >>>>>>>>    .
> >     /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >      >>>>>>>>    cd
> >     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >      >>>>>>>>    cd /usr/src/kernel
> >      >>>>>>>>    make oldconfig scripts
> >      >>>>>>>>    exit
> >      >>>>>>>>
> >      >>>>>>>> Finally, build your module using a Makefile like this
> >      >>>>>>>>
> >      >>>>>>>>    obj-m := hello-mod.o
> >      >>>>>>>>    all:
> >      >>>>>>>>          make -C $(SDKTARGETSYSROOT)/usr/src/kernel
> >     M=$(shell pwd)
> >      >>>>>>>>
> >      >>>>>>>>
> >      >>>>>>>> HTH,
> >      >>>>>>>> Chris
> >      >>>>>>>>
> >      >>>>>>>> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
> >      >>>>>>>>> Hello to the YOCTO community,
> >      >>>>>>>>>
> >      >>>>>>>>> I am using (to build the target for Beagle Bone Black)
> >     the following script:
> >      >>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto
> >      >>>>>>>>>
> >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
> >      >>>>>>>>>
> >      >>>>>>>>> The latest kernel I am using from the following repo:
> >      >>>>>>>>> https://github.com/jumpnow/meta-bbb
> >      >>>>>>>>>
> >      >>>>>>>>> Is kernel 5.0.14 .
> >      >>>>>>>>>
> >      >>>>>>>>> Here is the snippet of the boot traces:
> >      >>>>>>>>> Starting kernel ...
> >      >>>>>>>>>
> >      >>>>>>>>> [    0.000000] Booting Linux on physical CPU 0x0
> >      >>>>>>>>> [    0.000000] Linux version 5.0.14-jumpnow
> >     (oe-user@oe-host) (gcc
> >      >>>>>>>>> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> >      >>>>>>>>> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2
> >     (ARMv7), cr=10c5387d
> >      >>>>>>>>> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache,
> >     VIPT aliasing
> >      >>>>>>>>> instruction cache
> >      >>>>>>>>> [    0.000000] OF: fdt: Machine model: TI AM335x
> >     BeagleBone Black
> >      >>>>>>>>> [    0.000000] Memory policy: Data cache writeback
> >      >>>>>>>>> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> >      >>>>>>>>> [    0.000000] CPU: All CPU(s) started in SVC mode.
> >      >>>>>>>>> [    0.000000] AM335X ES2.1 (sgx neon)
> >      >>>>>>>>> [    0.000000] random: get_random_bytes called from
> >      >>>>>>>>> start_kernel+0xa4/0x460 with crng_init=0
> >      >>>>>>>>> [    0.000000] Built 1 zonelists, mobility grouping on.
> >     Total pages: 130048
> >      >>>>>>>>> [    0.000000] Kernel command line: console=ttyO0,115200n8
> >      >>>>>>>>> root=/dev/ram0 ip=dhcp
> >      >>>>>>>>>
> >      >>>>>>>>> According to the documentation, the following:
> >      >>>>>>>>> 2.10.1. Building Out-of-Tree Modules on the Target
> >      >>>>>>>>>
> >     https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
> >      >>>>>>>>>
> >      >>>>>>>>> I tried to find /usr/src/kernels/5.0.14.
> >     <http://5.0.14.>.. Directory, since I see
> >      >>>>>>>>> from the build that kernel-dev and kernel-devsrc are
> >     included:
> >      >>>>>>>>> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> >      >>>>>>>>> core-image-kernel-dev
>  :1.0-r0
> >      >>>>>>>>> kernel-devsrc
>  :1.0-r0
> >      >>>>>>>>> kernel-selftest
>  :1.0-r0
> >      >>>>>>>>>
> >      >>>>>>>>> THE PROBLEM: But I could not find ob BBB target
> >     /usr/src/kernels
> >      >>>>>>>>> directory at all!?
> >      >>>>>>>>>
> >      >>>>>>>>> Two questions here?
> >      >>>>>>>>> [1] Do you have any advice on this problem (what I am
> >     missing here)?
> >      >>>>>>>>> [2] Alternative to [1]: how I can use cross compiler from
> >      >>>>>>>>> .../build/tmp to build Out-of-Tree Module for the BBB
> >     target on the
> >      >>>>>>>>> host?
> >      >>>>>>>>>
> >      >>>>>>>>> Thank you,
> >      >>>>>>>>> Zoran
> >      >>>>>>>>> _______
> >      >>>>>>>>>
> >      >>>>>>>>
> >      >>>>>>>>
> >      >>>>>>>> --
> >      >>>>>>>> Chris Simmonds, trainer and consultant at 2net
> >      >>>>>>>> http://www.2net.co.uk
> >      >>>>>>>> Author of "Mastering Embedded Linux Programming"
> >      >>>>>>
> >      >>>>>>
> >      >>>>>>
> >      >>>>>> --
> >      >>>>>> - Thou shalt not follow the NULL pointer, for chaos and
> >     madness await thee at its end
> >      >>>>>> - "Use the force Harry" - Gandalf, Star Trek II
> >      >>>>>>
> >      >>>>
> >      >>>>
> >      >>>> --
> >      >>>> - Thou shalt not follow the NULL pointer, for chaos and
> >     madness await thee at its end
> >      >>>> - "Use the force Harry" - Gandalf, Star Trek II
> >      >>>>
> >      >>
> >      >>
> >      >>
> >      >> --
> >      >> - Thou shalt not follow the NULL pointer, for chaos and madness
> >     await thee at its end
> >      >> - "Use the force Harry" - Gandalf, Star Trek II
> >      >>
> >
>

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Re: Building Out-of-Tree Modules on the BBB Target

[Bruce Ashfield]

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On Thu, May 23, 2019 at 9:00 PM Khem Raj <raj.khem@gmail.com> wrote:

>
>
> On 5/23/19 3:32 AM, Zoran Stojsavljevic wrote:
> > After some tests (and I had other problems to take care of, as well),
> > here is the following:
> >
> >> These have all been discussed off an on over the past 5 years.
> >> I can't get at bugzilla right now, but all the details are logged in
> cases.
> >> A survey of all the distros, their kernel package, etc, were all looked
> at.
> >> We had to balance the traditional packaging with some new concepts
> >> and landed with what we have now.
> >
> > I tried several tests. This is my final conclusion (two cases):
> >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
> >
> > The kernel issue is described here: there is need to have the YOCTO
> > minimum configuration with the kernel setup:
> > [1] The entire kernel source code in:
> > /usr/src/kernel/`uname-r`/<kernel source code>
> > [2] The header files in: /usr/src/kernel/`uname-r`/<header file
> > directory structures>
> >
> > Point [1] is achieved with the following local.config file:
> >
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
> >
> > Namely, with the following snippets in the local.conf:
> > TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
> > packagegroup-core-buildessential kernel-devsrc"
> > KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
> > packagegroup-core-buildessential kernel-devsrc"
> > KERNEL_DEV_MODULE = "kernel-modules"
> > CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
> > ${KERNEL_DEV_TOOLS} \
> > systemtap \
> > "
> >
> > Problem with this approach is that such a kernel makes the rootfs too
> > big and impractical:
> > -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
> > core-image-minimal-beaglebone.rootfs.tar.xz
> >
> > The main issue is point [2]: how to achieve it?
> > The suggestion is to introduce the new package in YOCTO kernel,
> > called: kernel-headers
> > The OBVIOUS benefit is that it will serve to the purpose of building
> > modules out of the tree on the target with
> > minimal mpact to rootfs!
>
> I think this is a fair suggestion. Having prebuilt kernel available
> that contains the configuration and header files used in the build is
> all that is required for external modules to build in addition to
> toolchain, so maybe its worth a try to create such a package and then
> have kernel-source separated out which can be installed on top if one
> needs
>

That's exactly what the kernel-devsrc package is. It is about 90 Megs
(unpacked) and is the headers + config required to build out of tree
modules against the kernel.

I'm going to create two new optional packages for the fall release that are
simply captured kernel-source and kernel-headers for those uses cases where
someone really does want the entire source tree, or just the headers. The
details for that work are in bugzilla.

Bruce



>
> >
> > Thank you,
> > Zoran Stojsavljevic
> > _______
> >
> > On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
> > <bruce.ashfield@gmail.com> wrote:
> >>
> >>
> >>
> >> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >>>
> >>>> The core-image-kernel-dev image is how I do all my on target
> >>>> testing when I introduce a new reference kernel for a release.
> >>>
> >>> Maybe you are correct. Maybe I should use/add in my local.conf the
> following:
> >>>
> >>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
> >>> packagegroup-core-buildessential kernel-devsrc"
> >>> KERNEL_DEV_MODULE ?= "kernel-modules"
> >>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
> >>>                               ${KERNEL_DEV_TOOLS} \
> >>>                               systemtap \
> >>>                              "
> >>> I need to try these... Maybe this addendum will solve the $1 mio USD
> problem?!
> >>>
> >>>> And IIRC the autobuilders are using a sato based image (Richard
> >>>> could confirm more easily that I could what image type the
> >>>> autobuilders are using for hello-world on target module tests).
> >>>
> >>> I am just advertising something more simple. To have mandatory
> >>> /lib/modules/`uname -r` directory. And introduce few more packages, as
> >>> Fedora distro, for example, has: kernel-headers (assuming YOCTO
> >>> rootfs, the following will be installed: /usr/src/kernel/`uname
> >>> -r`/<header file directory structures>. This also makes addition of
> >>> /lib/modules/`uname -r`/build file (which is soft link to
> >>> usr/src/kernel/`uname -r`).
> >>
> >>
> >> These have all been discussed off an on over the past 5 years. I can't
> get at bugzilla right now, but all the details are logged in cases. A
> survey of all the distros, their kernel package, etc, were all looked at.
> We had to balance the traditional packaging with some new concepts and
> landed with what we have now.
> >>
> >>
> >>>
> >>> Or kernel-devel package. Then, the whole current kernel source code
> >>> will be introduced, and also support for it.
> >>
> >>
> >> There's a case for this one as well, I'll probably have it done for the
> fall release. But our devsrc used to pretty much be the full source it has
> now been pruned down to something more manageable.  There are definitely
> some cases for having the full source on the target again, and it will be a
> separate package, just not the minimal one to build out of tree modules,
> etc.
> >>
> >>
> >>
> >>>
> >>>
> >>> SDK building with such a support is good/cool. But sometimes, before
> >>> introducing SDK, some tests should be done on target. NO need to
> >>> optionally include built-in layer hello-world driver example. Since I
> >>> (or you name the person) have own test drivers, which will be imported
> >>> out of tree, externally, to the target test bed!
> >>>
> >>
> >> I never use the SDK myself, so you are not alone in not going to it
> first. Hopefully I'll get some new patches out in the coming month before
> summer holidays really kick in.
> >>
> >> Bruce
> >>
> >>
> >>>
> >>> Just thinking loud...
> >>>
> >>> Zoran
> >>> _______
> >>>
> >>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield <
> bruce.ashfield@gmail.com> wrote:
> >>>>
> >>>>
> >>>>
> >>>> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >>>>>
> >>>>>> That's correct. That command only adds the kernel source and
> >>>>>> build infrastructure to the SDK, not to your target image. You'd
> still
> >>>>>> need to arrange to have the kernel-devsrc package installed on the
> >>>>>> target image if you want it on the board's rootfs. How you arrange
> >>>>>> to have the package installed to the image varies with the image
> >>>>>> (since they all don't have the same image install variables, etc).
> >>>>>
> >>>>> And here is a $1,000,000 USD question? How to do it on Poky (as
> >>>>> example of what you have stated in RED)? ;-)
> >>>>>
> >>>>> In other words: how to arrange it on Poky (as a Referent example)?
> >>>>
> >>>>
> >>>> The core-image-kernel-dev image is how I do all my on target testing
> when I introduce a new reference kernel for a release. And IIRC the
> autobuilders are using a sato based image (Richard could confirm more
> easily that I could what image type the autobuilders are using for
> hello-world on target module tests).
> >>>>
> >>>> Bruce
> >>>>
> >>>>
> >>>>>
> >>>>>
> >>>>> Thank you,
> >>>>> Zoran
> >>>>> _______
> >>>>>
> >>>>>
> >>>>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <
> bruce.ashfield@gmail.com> wrote:
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
> >>>>>>>
> >>>>>>> Hello Chris, Bruce,
> >>>>>>>
> >>>>>>> I have some additional data to share with you both, since I have
> tried
> >>>>>>> something. And here is my take on the things!
> >>>>>>>
> >>>>>>>> 1. Build using a bb recipe.
> >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for an
> example.
> >>>>>>>> You just need to add meta-skeleton to your bblayers.conf and then
> >>>>>>>>   bitbake hello-mod
> >>>>>>>
> >>>>>>> I looked into this example, and, yes, it is classic kernel module
> >>>>>>> definition out of the tree. With some outdated data, all cool, the
> >>>>>>> YOCTO designer should take care himself to fix these data, if using
> >>>>>>> this stuff.
> >>>>>>>
> >>>>>>> But this is NOT mandatory, since I can add out of the tree module
> NOT
> >>>>>>> actually using built-in module. I just use
> .../tmp/deploy/images/bbb/*
> >>>>>>> generated stuff, since I have automated scripts which are bringing
> all
> >>>>>>> these on my BBB target. Then I tftp my source code module to the
> >>>>>>> target.
> >>>>>>>
> >>>>>>>> 2. Build from the SDK:
> >>>>>>>> First, add the kernel source to the SDK by adding this to
> conf/local.conf
> >>>>>>>>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >>>>>>>
> >>>>>>> YES, this is THE command which should generate
> >>>>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
> >>>>>>> local.conf and after deleting kernel, then regenerating bitbake -k
> >>>>>>> core-image-minimal does not bring this path into the rootfs image!?
> >>>>>>
> >>>>>>
> >>>>>> That's correct. That command only adds the kernel source and build
> infrastructure to the SDK, not to your target image. You'd still need to
> arrange to have the kernel-devsrc package installed on the target image if
> you want it on the board's rootfs. How you arrange to have the package
> installed to the image varies with the image (since they all don't have the
> same image install variables, etc).
> >>>>>>
> >>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>> I did it actually using meta-bbb, and using poky referent distro as
> >>>>>>> two additional layers to the more complex bbb image!
> >>>>>>> https://github.com/jumpnow/meta-bbb.git
> >>>>>>>
> >>>>>>> The (KAS - you can figure out out of it local.conf) script I am
> using
> >>>>>>> to build such a BBB image is here:
> >>>>>>>
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
> >>>>>>>
> >>>>>>> I did not try it with BBB reference poky only! Maybe I should try
> it
> >>>>>>> as only referent poky? What do you think?
> >>>>>>>
> >>>>>>> Does in this case is SDK build really mandatory??? Should NOT be!
> >>>>>>>
> >>>>>>
> >>>>>> You only do the SDK steps if you want to support building out of
> tree modules in an SDK install. So it is not mandatory for on target module
> builds.
> >>>>>>
> >>>>>> Bruce
> >>>>>>
> >>>>>>
> >>>>>>>
> >>>>>>>> Once the SDK is installed, generate the kernel headers:
> >>>>>>>>   sudo -i
> >>>>>>>>   .
> /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >>>>>>>>   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >>>>>>>>   cd /usr/src/kernel
> >>>>>>>>   make oldconfig scripts
> >>>>>>>>   exit
> >>>>>>>
> >>>>>>> This is in nutshell the same what I did (a bit different) for
> Embedded
> >>>>>>> Debian. This is already on the target BBB, NOT while building YOCTO
> >>>>>>> BBB image!
> >>>>>>>
> >>>>>>>> Finally, build your module using a Makefile like this
> >>>>>>>>   obj-m := hello-mod.o
> >>>>>>>>   all:
> >>>>>>>>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
> >>>>>>>
> >>>>>>> As said before: bringing my own module into the target BBB (I have
> my
> >>>>>>> own examples, and I build them on the target with the almost the
> same
> >>>>>>> Makefiles)
> >>>>>>>
> >>>>>>> Zoran
> >>>>>>> _______
> >>>>>>>
> >>>>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk>
> wrote:
> >>>>>>>>
> >>>>>>>> Hi Zoran,
> >>>>>>>>
> >>>>>>>> There are two ways to do this
> >>>>>>>>
> >>>>>>>> 1. Build using a bb recipe.
> >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for an
> example.
> >>>>>>>> You just need to add meta-skeleton to your bblaysers.conf and then
> >>>>>>>>    bitbake hello-mod
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> 2. Build from the SDK:
> >>>>>>>> First, add the kernel source to the SDK by adding this to
> conf/local/conf
> >>>>>>>>    TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
> >>>>>>>>
> >>>>>>>> Then build the SDK
> >>>>>>>>    bitbake -c populate_sdk [your image recipe]
> >>>>>>>>
> >>>>>>>> Once the SDK is installed, generate the kernel headers:
> >>>>>>>>    sudo -i
> >>>>>>>>    .
> /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
> >>>>>>>>    cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
> >>>>>>>>    cd /usr/src/kernel
> >>>>>>>>    make oldconfig scripts
> >>>>>>>>    exit
> >>>>>>>>
> >>>>>>>> Finally, build your module using a Makefile like this
> >>>>>>>>
> >>>>>>>>    obj-m := hello-mod.o
> >>>>>>>>    all:
> >>>>>>>>          make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> HTH,
> >>>>>>>> Chris
> >>>>>>>>
> >>>>>>>> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
> >>>>>>>>> Hello to the YOCTO community,
> >>>>>>>>>
> >>>>>>>>> I am using (to build the target for Beagle Bone Black) the
> following script:
> >>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto
> >>>>>>>>>
> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
> >>>>>>>>>
> >>>>>>>>> The latest kernel I am using from the following repo:
> >>>>>>>>> https://github.com/jumpnow/meta-bbb
> >>>>>>>>>
> >>>>>>>>> Is kernel 5.0.14 .
> >>>>>>>>>
> >>>>>>>>> Here is the snippet of the boot traces:
> >>>>>>>>> Starting kernel ...
> >>>>>>>>>
> >>>>>>>>> [    0.000000] Booting Linux on physical CPU 0x0
> >>>>>>>>> [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host)
> (gcc
> >>>>>>>>> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
> >>>>>>>>> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2
> (ARMv7), cr=10c5387d
> >>>>>>>>> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT
> aliasing
> >>>>>>>>> instruction cache
> >>>>>>>>> [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
> >>>>>>>>> [    0.000000] Memory policy: Data cache writeback
> >>>>>>>>> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
> >>>>>>>>> [    0.000000] CPU: All CPU(s) started in SVC mode.
> >>>>>>>>> [    0.000000] AM335X ES2.1 (sgx neon)
> >>>>>>>>> [    0.000000] random: get_random_bytes called from
> >>>>>>>>> start_kernel+0xa4/0x460 with crng_init=0
> >>>>>>>>> [    0.000000] Built 1 zonelists, mobility grouping on.  Total
> pages: 130048
> >>>>>>>>> [    0.000000] Kernel command line: console=ttyO0,115200n8
> >>>>>>>>> root=/dev/ram0 ip=dhcp
> >>>>>>>>>
> >>>>>>>>> According to the documentation, the following:
> >>>>>>>>> 2.10.1. Building Out-of-Tree Modules on the Target
> >>>>>>>>>
> https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
> >>>>>>>>>
> >>>>>>>>> I tried to find /usr/src/kernels/5.0.14... Directory, since I
> see
> >>>>>>>>> from the build that kernel-dev and kernel-devsrc are included:
> >>>>>>>>> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
> >>>>>>>>> core-image-kernel-dev                                 :1.0-r0
> >>>>>>>>> kernel-devsrc                                         :1.0-r0
> >>>>>>>>> kernel-selftest                                       :1.0-r0
> >>>>>>>>>
> >>>>>>>>> THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
> >>>>>>>>> directory at all!?
> >>>>>>>>>
> >>>>>>>>> Two questions here?
> >>>>>>>>> [1] Do you have any advice on this problem (what I am missing
> here)?
> >>>>>>>>> [2] Alternative to [1]: how I can use cross compiler from
> >>>>>>>>> .../build/tmp to build Out-of-Tree Module for the BBB target on
> the
> >>>>>>>>> host?
> >>>>>>>>>
> >>>>>>>>> Thank you,
> >>>>>>>>> Zoran
> >>>>>>>>> _______
> >>>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> --
> >>>>>>>> Chris Simmonds, trainer and consultant at 2net
> >>>>>>>> http://www.2net.co.uk
> >>>>>>>> Author of "Mastering Embedded Linux Programming"
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> --
> >>>>>> - Thou shalt not follow the NULL pointer, for chaos and madness
> await thee at its end
> >>>>>> - "Use the force Harry" - Gandalf, Star Trek II
> >>>>>>
> >>>>
> >>>>
> >>>> --
> >>>> - Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end
> >>>> - "Use the force Harry" - Gandalf, Star Trek II
> >>>>
> >>
> >>
> >>
> >> --
> >> - Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end
> >> - "Use the force Harry" - Gandalf, Star Trek II
> >>
>


-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

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Re: Building Out-of-Tree Modules on the BBB Target

[Bruce Ashfield]

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On Fri, May 24, 2019 at 7:24 AM Zoran Stojsavljevic <
zoran.stojsavljevic@gmail.com> wrote:

> As I said, I am a man of experimental try-outs. And here is the try!
>
> Now, after setting sources, I tried to compile the example (from my Git):
> https://github.com/ZoranStojsavljevic/bbb-yocto/tree/master/Issues/LKM
>
> The results are the following (all on the target):
> root@beaglebone:~# pwd
> /home/root
> root@beaglebone:~# ls -al
> drwx------    2 root     root             0 May 24 13:11 .
> drwxr-xr-x    3 root     root             0 May 23 13:03 ..
> -rw-r--r--    1 root     root           159 May 24 12:54 Makefile
> -rw-r--r--    1 root     root          1228 May 24 12:54 p15_test.c
> root@beaglebone:~# make all
> make -C /lib/modules/5.0.15-jumpnow/build M=/home/root modules
> make[1]: Entering directory '/lib/modules/5.0.15-jumpnow/build'
>   CC [M]  /home/root/p15_test.o
> In file included from ./include/asm-generic/int-ll64.h:11,
>                  from ./arch/arm/include/uapi/asm/types.h:5,
>                  from ./include/uapi/linux/types.h:5,
>                  from ./include/linux/types.h:6,
>                  from ./include/linux/list.h:5,
>                  from ./include/linux/module.h:9,
>                  from /home/root/p15_test.c:5:
> *./include/uapi/asm-generic/int-ll64.h:12:10: fatal error:
> asm/bitsperlong.h: No such file or directory*
>  #include <asm/bitsperlong.h>
>           ^~~~~~~~~~~~~~~~~~~
> compilation terminated.
>
>
>
> *make[2]: *** [scripts/Makefile.build:283: /home/root/p15_test.o] Error
> 1make[1]: *** [Makefile:1577: _module_/home/root] Error 2make[1]: Leaving
> directory '/lib/modules/5.0.15-jumpnow/build'make: *** [Makefile:4: all]
> Error 2*
>

I'll try some test builds and see what I can find. Some new issues may have
crept in.

Cheers,

Bruce



>
> I see that you have changed the kernel from 5.0.7-jumpnow to
> 5.0.15-jumpnow . Did you?
>
> This example works on the same target out of Debian (flashed in eMMC),
> without the problems.
>
> Something is wrong with the YOCTO source kernel tree.
>
> You are free to try example on YOCTO and Embedded Debian yourselves!
>
> Zoran
> _______
>
> On Fri, May 24, 2019 at 6:37 AM Khem Raj <raj.khem@gmail.com> wrote:
>
>>
>>
>> On 5/23/19 9:14 PM, Zoran Stojsavljevic wrote:
>> >  > I think this is a fair suggestion. Having prebuilt kernel available
>> >  > that contains the configuration and header files used in the build is
>> >  > all that is required for external modules to build in addition to
>> >  > toolchain, so maybe its worth a try to create such a package and then
>> >  > have kernel-source separated out which can be installed on top if one
>> >  > needs
>> >
>> > I am man of experimental try-outs. So, in order to see how big kernel
>> is,
>> > I did the following:
>> > Fedora 29 (which I am using as a host) with kernel-headers (NOT full
>> > kernel source tree):
>> > [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ pwd
>> > /usr/src/kernels/5.0.16-200.fc29.x86_64
>> > [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ du --summarize
>> > /*102124    . <<======= ~95MB*/
>> >
>> > Kernel.org kernel 5.0.6, the full kernel source tree size:
>> > [vuser@fedora29-ssd linux-5.0.6]$ pwd
>> > /home/vuser/projects/kernel.org/linux-5.0.6 <
>> http://kernel.org/linux-5.0.6>
>> > [vuser@fedora29-ssd linux-5.0.6]$ du --summarize
>> > /*960592    . <<======= ~900MB*/
>> >
>> > These are ballpark numbers. You can draw conclusions for yourselves!
>> >
>> > It is ~ 7x to 9x reduction in size. Having BBB's DDR2 of size 512MB,
>> > and initramfs for testing purposes, in speaks for itself.
>> >
>>
>> yes thats what I was expecting too. Anything smaller helps.
>>
>>
>> > (I am aware that YOCTO kernels are less/smaller in size, but how
>> smaller?)
>> >
>>
>> Not in source. The binaries may be
>>
>> > Zoran
>> > _______
>> >
>> >
>> > On Fri, May 24, 2019 at 3:00 AM Khem Raj <raj.khem@gmail.com
>> > <mailto:raj.khem@gmail.com>> wrote:
>> >
>> >
>> >
>> >     On 5/23/19 3:32 AM, Zoran Stojsavljevic wrote:
>> >      > After some tests (and I had other problems to take care of, as
>> well),
>> >      > here is the following:
>> >      >
>> >      >> These have all been discussed off an on over the past 5 years.
>> >      >> I can't get at bugzilla right now, but all the details are
>> >     logged in cases.
>> >      >> A survey of all the distros, their kernel package, etc, were all
>> >     looked at.
>> >      >> We had to balance the traditional packaging with some new
>> concepts
>> >      >> and landed with what we have now.
>> >      >
>> >      > I tried several tests. This is my final conclusion (two cases):
>> >      >
>> >
>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
>> >      >
>> >      > The kernel issue is described here: there is need to have the
>> YOCTO
>> >      > minimum configuration with the kernel setup:
>> >      > [1] The entire kernel source code in:
>> >      > /usr/src/kernel/`uname-r`/<kernel source code>
>> >      > [2] The header files in: /usr/src/kernel/`uname-r`/<header file
>> >      > directory structures>
>> >      >
>> >      > Point [1] is achieved with the following local.config file:
>> >      >
>> >
>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
>> >      >
>> >      > Namely, with the following snippets in the local.conf:
>> >      > TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
>> >      > packagegroup-core-buildessential kernel-devsrc"
>> >      > KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
>> >      > packagegroup-core-buildessential kernel-devsrc"
>> >      > KERNEL_DEV_MODULE = "kernel-modules"
>> >      > CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>> >      > ${KERNEL_DEV_TOOLS} \
>> >      > systemtap \
>> >      > "
>> >      >
>> >      > Problem with this approach is that such a kernel makes the
>> rootfs too
>> >      > big and impractical:
>> >      > -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
>> >      > core-image-minimal-beaglebone.rootfs.tar.xz
>> >      >
>> >      > The main issue is point [2]: how to achieve it?
>> >      > The suggestion is to introduce the new package in YOCTO kernel,
>> >      > called: kernel-headers
>> >      > The OBVIOUS benefit is that it will serve to the purpose of
>> building
>> >      > modules out of the tree on the target with
>> >      > minimal mpact to rootfs!
>> >
>> >     I think this is a fair suggestion. Having prebuilt kernel available
>> >     that contains the configuration and header files used in the build
>> is
>> >     all that is required for external modules to build in addition to
>> >     toolchain, so maybe its worth a try to create such a package and
>> then
>> >     have kernel-source separated out which can be installed on top if
>> one
>> >     needs
>> >
>> >      >
>> >      > Thank you,
>> >      > Zoran Stojsavljevic
>> >      > _______
>> >      >
>> >      > On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
>> >      > <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>>
>> wrote:
>> >      >>
>> >      >>
>> >      >>
>> >      >> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic
>> >     <zoran.stojsavljevic@gmail.com
>> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>> >      >>>
>> >      >>>> The core-image-kernel-dev image is how I do all my on target
>> >      >>>> testing when I introduce a new reference kernel for a release.
>> >      >>>
>> >      >>> Maybe you are correct. Maybe I should use/add in my local.conf
>> >     the following:
>> >      >>>
>> >      >>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
>> >      >>> packagegroup-core-buildessential kernel-devsrc"
>> >      >>> KERNEL_DEV_MODULE ?= "kernel-modules"
>> >      >>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>> >      >>>                               ${KERNEL_DEV_TOOLS} \
>> >      >>>                               systemtap \
>> >      >>>                              "
>> >      >>> I need to try these... Maybe this addendum will solve the $1
>> >     mio USD problem?!
>> >      >>>
>> >      >>>> And IIRC the autobuilders are using a sato based image
>> (Richard
>> >      >>>> could confirm more easily that I could what image type the
>> >      >>>> autobuilders are using for hello-world on target module
>> tests).
>> >      >>>
>> >      >>> I am just advertising something more simple. To have mandatory
>> >      >>> /lib/modules/`uname -r` directory. And introduce few more
>> >     packages, as
>> >      >>> Fedora distro, for example, has: kernel-headers (assuming YOCTO
>> >      >>> rootfs, the following will be installed: /usr/src/kernel/`uname
>> >      >>> -r`/<header file directory structures>. This also makes
>> addition of
>> >      >>> /lib/modules/`uname -r`/build file (which is soft link to
>> >      >>> usr/src/kernel/`uname -r`).
>> >      >>
>> >      >>
>> >      >> These have all been discussed off an on over the past 5 years. I
>> >     can't get at bugzilla right now, but all the details are logged in
>> >     cases. A survey of all the distros, their kernel package, etc, were
>> >     all looked at. We had to balance the traditional packaging with some
>> >     new concepts and landed with what we have now.
>> >      >>
>> >      >>
>> >      >>>
>> >      >>> Or kernel-devel package. Then, the whole current kernel source
>> code
>> >      >>> will be introduced, and also support for it.
>> >      >>
>> >      >>
>> >      >> There's a case for this one as well, I'll probably have it done
>> >     for the fall release. But our devsrc used to pretty much be the full
>> >     source it has now been pruned down to something more manageable.
>> >     There are definitely some cases for having the full source on the
>> >     target again, and it will be a separate package, just not the
>> >     minimal one to build out of tree modules, etc.
>> >      >>
>> >      >>
>> >      >>
>> >      >>>
>> >      >>>
>> >      >>> SDK building with such a support is good/cool. But sometimes,
>> >     before
>> >      >>> introducing SDK, some tests should be done on target. NO need
>> to
>> >      >>> optionally include built-in layer hello-world driver example.
>> >     Since I
>> >      >>> (or you name the person) have own test drivers, which will be
>> >     imported
>> >      >>> out of tree, externally, to the target test bed!
>> >      >>>
>> >      >>
>> >      >> I never use the SDK myself, so you are not alone in not going to
>> >     it first. Hopefully I'll get some new patches out in the coming
>> >     month before summer holidays really kick in.
>> >      >>
>> >      >> Bruce
>> >      >>
>> >      >>
>> >      >>>
>> >      >>> Just thinking loud...
>> >      >>>
>> >      >>> Zoran
>> >      >>> _______
>> >      >>>
>> >      >>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield
>> >     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
>> >      >>>>
>> >      >>>>
>> >      >>>>
>> >      >>>> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic
>> >     <zoran.stojsavljevic@gmail.com
>> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>> >      >>>>>
>> >      >>>>>> That's correct. That command only adds the kernel source and
>> >      >>>>>> build infrastructure to the SDK, not to your target image.
>> >     You'd still
>> >      >>>>>> need to arrange to have the kernel-devsrc package installed
>> >     on the
>> >      >>>>>> target image if you want it on the board's rootfs. How you
>> >     arrange
>> >      >>>>>> to have the package installed to the image varies with the
>> image
>> >      >>>>>> (since they all don't have the same image install variables,
>> >     etc).
>> >      >>>>>
>> >      >>>>> And here is a $1,000,000 USD question? How to do it on Poky
>> (as
>> >      >>>>> example of what you have stated in RED)? ;-)
>> >      >>>>>
>> >      >>>>> In other words: how to arrange it on Poky (as a Referent
>> >     example)?
>> >      >>>>
>> >      >>>>
>> >      >>>> The core-image-kernel-dev image is how I do all my on target
>> >     testing when I introduce a new reference kernel for a release. And
>> >     IIRC the autobuilders are using a sato based image (Richard could
>> >     confirm more easily that I could what image type the autobuilders
>> >     are using for hello-world on target module tests).
>> >      >>>>
>> >      >>>> Bruce
>> >      >>>>
>> >      >>>>
>> >      >>>>>
>> >      >>>>>
>> >      >>>>> Thank you,
>> >      >>>>> Zoran
>> >      >>>>> _______
>> >      >>>>>
>> >      >>>>>
>> >      >>>>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield
>> >     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
>> >      >>>>>>
>> >      >>>>>>
>> >      >>>>>>
>> >      >>>>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic
>> >     <zoran.stojsavljevic@gmail.com
>> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>> >      >>>>>>>
>> >      >>>>>>> Hello Chris, Bruce,
>> >      >>>>>>>
>> >      >>>>>>> I have some additional data to share with you both, since I
>> >     have tried
>> >      >>>>>>> something. And here is my take on the things!
>> >      >>>>>>>
>> >      >>>>>>>> 1. Build using a bb recipe.
>> >      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
>> >     an example.
>> >      >>>>>>>> You just need to add meta-skeleton to your bblayers.conf
>> >     and then
>> >      >>>>>>>>   bitbake hello-mod
>> >      >>>>>>>
>> >      >>>>>>> I looked into this example, and, yes, it is classic kernel
>> >     module
>> >      >>>>>>> definition out of the tree. With some outdated data, all
>> >     cool, the
>> >      >>>>>>> YOCTO designer should take care himself to fix these data,
>> >     if using
>> >      >>>>>>> this stuff.
>> >      >>>>>>>
>> >      >>>>>>> But this is NOT mandatory, since I can add out of the tree
>> >     module NOT
>> >      >>>>>>> actually using built-in module. I just use
>> >     .../tmp/deploy/images/bbb/*
>> >      >>>>>>> generated stuff, since I have automated scripts which are
>> >     bringing all
>> >      >>>>>>> these on my BBB target. Then I tftp my source code module
>> >     to the
>> >      >>>>>>> target.
>> >      >>>>>>>
>> >      >>>>>>>> 2. Build from the SDK:
>> >      >>>>>>>> First, add the kernel source to the SDK by adding this to
>> >     conf/local.conf
>> >      >>>>>>>>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>> >      >>>>>>>
>> >      >>>>>>> YES, this is THE command which should generate
>> >      >>>>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it
>> to
>> >      >>>>>>> local.conf and after deleting kernel, then regenerating
>> >     bitbake -k
>> >      >>>>>>> core-image-minimal does not bring this path into the rootfs
>> >     image!?
>> >      >>>>>>
>> >      >>>>>>
>> >      >>>>>> That's correct. That command only adds the kernel source and
>> >     build infrastructure to the SDK, not to your target image. You'd
>> >     still need to arrange to have the kernel-devsrc package installed on
>> >     the target image if you want it on the board's rootfs. How you
>> >     arrange to have the package installed to the image varies with the
>> >     image (since they all don't have the same image install variables,
>> etc).
>> >      >>>>>>
>> >      >>>>>>
>> >      >>>>>>>
>> >      >>>>>>>
>> >      >>>>>>> I did it actually using meta-bbb, and using poky referent
>> >     distro as
>> >      >>>>>>> two additional layers to the more complex bbb image!
>> >      >>>>>>> https://github.com/jumpnow/meta-bbb.git
>> >      >>>>>>>
>> >      >>>>>>> The (KAS - you can figure out out of it local.conf) script
>> >     I am using
>> >      >>>>>>> to build such a BBB image is here:
>> >      >>>>>>>
>> >
>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>> >      >>>>>>>
>> >      >>>>>>> I did not try it with BBB reference poky only! Maybe I
>> >     should try it
>> >      >>>>>>> as only referent poky? What do you think?
>> >      >>>>>>>
>> >      >>>>>>> Does in this case is SDK build really mandatory??? Should
>> >     NOT be!
>> >      >>>>>>>
>> >      >>>>>>
>> >      >>>>>> You only do the SDK steps if you want to support building
>> >     out of tree modules in an SDK install. So it is not mandatory for on
>> >     target module builds.
>> >      >>>>>>
>> >      >>>>>> Bruce
>> >      >>>>>>
>> >      >>>>>>
>> >      >>>>>>>
>> >      >>>>>>>> Once the SDK is installed, generate the kernel headers:
>> >      >>>>>>>>   sudo -i
>> >      >>>>>>>>   .
>> >     /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>> >      >>>>>>>>   cd
>> >     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>> >      >>>>>>>>   cd /usr/src/kernel
>> >      >>>>>>>>   make oldconfig scripts
>> >      >>>>>>>>   exit
>> >      >>>>>>>
>> >      >>>>>>> This is in nutshell the same what I did (a bit different)
>> >     for Embedded
>> >      >>>>>>> Debian. This is already on the target BBB, NOT while
>> >     building YOCTO
>> >      >>>>>>> BBB image!
>> >      >>>>>>>
>> >      >>>>>>>> Finally, build your module using a Makefile like this
>> >      >>>>>>>>   obj-m := hello-mod.o
>> >      >>>>>>>>   all:
>> >      >>>>>>>>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel
>> >     M=$(shell pwd)
>> >      >>>>>>>
>> >      >>>>>>> As said before: bringing my own module into the target BBB
>> >     (I have my
>> >      >>>>>>> own examples, and I build them on the target with the
>> >     almost the same
>> >      >>>>>>> Makefiles)
>> >      >>>>>>>
>> >      >>>>>>> Zoran
>> >      >>>>>>> _______
>> >      >>>>>>>
>> >      >>>>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds
>> >     <chris@2net.co.uk <mailto:chris@2net.co.uk>> wrote:
>> >      >>>>>>>>
>> >      >>>>>>>> Hi Zoran,
>> >      >>>>>>>>
>> >      >>>>>>>> There are two ways to do this
>> >      >>>>>>>>
>> >      >>>>>>>> 1. Build using a bb recipe.
>> >      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
>> >     an example.
>> >      >>>>>>>> You just need to add meta-skeleton to your bblaysers.conf
>> >     and then
>> >      >>>>>>>>    bitbake hello-mod
>> >      >>>>>>>>
>> >      >>>>>>>>
>> >      >>>>>>>> 2. Build from the SDK:
>> >      >>>>>>>> First, add the kernel source to the SDK by adding this to
>> >     conf/local/conf
>> >      >>>>>>>>    TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>> >      >>>>>>>>
>> >      >>>>>>>> Then build the SDK
>> >      >>>>>>>>    bitbake -c populate_sdk [your image recipe]
>> >      >>>>>>>>
>> >      >>>>>>>> Once the SDK is installed, generate the kernel headers:
>> >      >>>>>>>>    sudo -i
>> >      >>>>>>>>    .
>> >     /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>> >      >>>>>>>>    cd
>> >     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>> >      >>>>>>>>    cd /usr/src/kernel
>> >      >>>>>>>>    make oldconfig scripts
>> >      >>>>>>>>    exit
>> >      >>>>>>>>
>> >      >>>>>>>> Finally, build your module using a Makefile like this
>> >      >>>>>>>>
>> >      >>>>>>>>    obj-m := hello-mod.o
>> >      >>>>>>>>    all:
>> >      >>>>>>>>          make -C $(SDKTARGETSYSROOT)/usr/src/kernel
>> >     M=$(shell pwd)
>> >      >>>>>>>>
>> >      >>>>>>>>
>> >      >>>>>>>> HTH,
>> >      >>>>>>>> Chris
>> >      >>>>>>>>
>> >      >>>>>>>> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>> >      >>>>>>>>> Hello to the YOCTO community,
>> >      >>>>>>>>>
>> >      >>>>>>>>> I am using (to build the target for Beagle Bone Black)
>> >     the following script:
>> >      >>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto
>> >      >>>>>>>>>
>> >
>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>> >      >>>>>>>>>
>> >      >>>>>>>>> The latest kernel I am using from the following repo:
>> >      >>>>>>>>> https://github.com/jumpnow/meta-bbb
>> >      >>>>>>>>>
>> >      >>>>>>>>> Is kernel 5.0.14 .
>> >      >>>>>>>>>
>> >      >>>>>>>>> Here is the snippet of the boot traces:
>> >      >>>>>>>>> Starting kernel ...
>> >      >>>>>>>>>
>> >      >>>>>>>>> [    0.000000] Booting Linux on physical CPU 0x0
>> >      >>>>>>>>> [    0.000000] Linux version 5.0.14-jumpnow
>> >     (oe-user@oe-host) (gcc
>> >      >>>>>>>>> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>> >      >>>>>>>>> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2
>> >     (ARMv7), cr=10c5387d
>> >      >>>>>>>>> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache,
>> >     VIPT aliasing
>> >      >>>>>>>>> instruction cache
>> >      >>>>>>>>> [    0.000000] OF: fdt: Machine model: TI AM335x
>> >     BeagleBone Black
>> >      >>>>>>>>> [    0.000000] Memory policy: Data cache writeback
>> >      >>>>>>>>> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>> >      >>>>>>>>> [    0.000000] CPU: All CPU(s) started in SVC mode.
>> >      >>>>>>>>> [    0.000000] AM335X ES2.1 (sgx neon)
>> >      >>>>>>>>> [    0.000000] random: get_random_bytes called from
>> >      >>>>>>>>> start_kernel+0xa4/0x460 with crng_init=0
>> >      >>>>>>>>> [    0.000000] Built 1 zonelists, mobility grouping on.
>> >     Total pages: 130048
>> >      >>>>>>>>> [    0.000000] Kernel command line:
>> console=ttyO0,115200n8
>> >      >>>>>>>>> root=/dev/ram0 ip=dhcp
>> >      >>>>>>>>>
>> >      >>>>>>>>> According to the documentation, the following:
>> >      >>>>>>>>> 2.10.1. Building Out-of-Tree Modules on the Target
>> >      >>>>>>>>>
>> >     https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>> >      >>>>>>>>>
>> >      >>>>>>>>> I tried to find /usr/src/kernels/5.0.14.
>> >     <http://5.0.14.>.. Directory, since I see
>> >      >>>>>>>>> from the build that kernel-dev and kernel-devsrc are
>> >     included:
>> >      >>>>>>>>> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>> >      >>>>>>>>> core-image-kernel-dev
>>  :1.0-r0
>> >      >>>>>>>>> kernel-devsrc
>>  :1.0-r0
>> >      >>>>>>>>> kernel-selftest
>>  :1.0-r0
>> >      >>>>>>>>>
>> >      >>>>>>>>> THE PROBLEM: But I could not find ob BBB target
>> >     /usr/src/kernels
>> >      >>>>>>>>> directory at all!?
>> >      >>>>>>>>>
>> >      >>>>>>>>> Two questions here?
>> >      >>>>>>>>> [1] Do you have any advice on this problem (what I am
>> >     missing here)?
>> >      >>>>>>>>> [2] Alternative to [1]: how I can use cross compiler from
>> >      >>>>>>>>> .../build/tmp to build Out-of-Tree Module for the BBB
>> >     target on the
>> >      >>>>>>>>> host?
>> >      >>>>>>>>>
>> >      >>>>>>>>> Thank you,
>> >      >>>>>>>>> Zoran
>> >      >>>>>>>>> _______
>> >      >>>>>>>>>
>> >      >>>>>>>>
>> >      >>>>>>>>
>> >      >>>>>>>> --
>> >      >>>>>>>> Chris Simmonds, trainer and consultant at 2net
>> >      >>>>>>>> http://www.2net.co.uk
>> >      >>>>>>>> Author of "Mastering Embedded Linux Programming"
>> >      >>>>>>
>> >      >>>>>>
>> >      >>>>>>
>> >      >>>>>> --
>> >      >>>>>> - Thou shalt not follow the NULL pointer, for chaos and
>> >     madness await thee at its end
>> >      >>>>>> - "Use the force Harry" - Gandalf, Star Trek II
>> >      >>>>>>
>> >      >>>>
>> >      >>>>
>> >      >>>> --
>> >      >>>> - Thou shalt not follow the NULL pointer, for chaos and
>> >     madness await thee at its end
>> >      >>>> - "Use the force Harry" - Gandalf, Star Trek II
>> >      >>>>
>> >      >>
>> >      >>
>> >      >>
>> >      >> --
>> >      >> - Thou shalt not follow the NULL pointer, for chaos and madness
>> >     await thee at its end
>> >      >> - "Use the force Harry" - Gandalf, Star Trek II
>> >      >>
>> >
>>
>

-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

[-- Attachment #2: Type: text/html, Size: 38510 bytes --]

Re: Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

> I'm going to create two new optional packages for the fall release
> that are simply captured kernel-source and kernel-headers for
> those uses cases where someone really does want the entire
> source tree, or just the headers. The details for that work are in
> bugzilla.

Could you, please, point to me which YOCTO bugzilla this is? I would
like to capture these in the
https://github.com/ZoranStojsavljevic/bbb-yocto/tree/master/Issues,
just to have them as addition/addendum to all this what we have
discussed here?

Thank you,
Zoran

(PS. I'll continue some investigation as well)
_______


On Fri, May 24, 2019 at 2:48 PM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>
>
>
> On Thu, May 23, 2019 at 9:00 PM Khem Raj <raj.khem@gmail.com> wrote:
>>
>>
>>
>> On 5/23/19 3:32 AM, Zoran Stojsavljevic wrote:
>> > After some tests (and I had other problems to take care of, as well),
>> > here is the following:
>> >
>> >> These have all been discussed off an on over the past 5 years.
>> >> I can't get at bugzilla right now, but all the details are logged in cases.
>> >> A survey of all the distros, their kernel package, etc, were all looked at.
>> >> We had to balance the traditional packaging with some new concepts
>> >> and landed with what we have now.
>> >
>> > I tried several tests. This is my final conclusion (two cases):
>> > https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
>> >
>> > The kernel issue is described here: there is need to have the YOCTO
>> > minimum configuration with the kernel setup:
>> > [1] The entire kernel source code in:
>> > /usr/src/kernel/`uname-r`/<kernel source code>
>> > [2] The header files in: /usr/src/kernel/`uname-r`/<header file
>> > directory structures>
>> >
>> > Point [1] is achieved with the following local.config file:
>> > https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
>> >
>> > Namely, with the following snippets in the local.conf:
>> > TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
>> > packagegroup-core-buildessential kernel-devsrc"
>> > KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
>> > packagegroup-core-buildessential kernel-devsrc"
>> > KERNEL_DEV_MODULE = "kernel-modules"
>> > CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>> > ${KERNEL_DEV_TOOLS} \
>> > systemtap \
>> > "
>> >
>> > Problem with this approach is that such a kernel makes the rootfs too
>> > big and impractical:
>> > -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
>> > core-image-minimal-beaglebone.rootfs.tar.xz
>> >
>> > The main issue is point [2]: how to achieve it?
>> > The suggestion is to introduce the new package in YOCTO kernel,
>> > called: kernel-headers
>> > The OBVIOUS benefit is that it will serve to the purpose of building
>> > modules out of the tree on the target with
>> > minimal mpact to rootfs!
>>
>> I think this is a fair suggestion. Having prebuilt kernel available
>> that contains the configuration and header files used in the build is
>> all that is required for external modules to build in addition to
>> toolchain, so maybe its worth a try to create such a package and then
>> have kernel-source separated out which can be installed on top if one
>> needs
>
>
> That's exactly what the kernel-devsrc package is. It is about 90 Megs (unpacked) and is the headers + config required to build out of tree modules against the kernel.
>
> I'm going to create two new optional packages for the fall release that are simply captured kernel-source and kernel-headers for those uses cases where someone really does want the entire source tree, or just the headers. The details for that work are in bugzilla.
>
> Bruce
>
>
>>
>>
>> >
>> > Thank you,
>> > Zoran Stojsavljevic
>> > _______
>> >
>> > On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
>> > <bruce.ashfield@gmail.com> wrote:
>> >>
>> >>
>> >>
>> >> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>> >>>
>> >>>> The core-image-kernel-dev image is how I do all my on target
>> >>>> testing when I introduce a new reference kernel for a release.
>> >>>
>> >>> Maybe you are correct. Maybe I should use/add in my local.conf the following:
>> >>>
>> >>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
>> >>> packagegroup-core-buildessential kernel-devsrc"
>> >>> KERNEL_DEV_MODULE ?= "kernel-modules"
>> >>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>> >>>                               ${KERNEL_DEV_TOOLS} \
>> >>>                               systemtap \
>> >>>                              "
>> >>> I need to try these... Maybe this addendum will solve the $1 mio USD problem?!
>> >>>
>> >>>> And IIRC the autobuilders are using a sato based image (Richard
>> >>>> could confirm more easily that I could what image type the
>> >>>> autobuilders are using for hello-world on target module tests).
>> >>>
>> >>> I am just advertising something more simple. To have mandatory
>> >>> /lib/modules/`uname -r` directory. And introduce few more packages, as
>> >>> Fedora distro, for example, has: kernel-headers (assuming YOCTO
>> >>> rootfs, the following will be installed: /usr/src/kernel/`uname
>> >>> -r`/<header file directory structures>. This also makes addition of
>> >>> /lib/modules/`uname -r`/build file (which is soft link to
>> >>> usr/src/kernel/`uname -r`).
>> >>
>> >>
>> >> These have all been discussed off an on over the past 5 years. I can't get at bugzilla right now, but all the details are logged in cases. A survey of all the distros, their kernel package, etc, were all looked at. We had to balance the traditional packaging with some new concepts and landed with what we have now.
>> >>
>> >>
>> >>>
>> >>> Or kernel-devel package. Then, the whole current kernel source code
>> >>> will be introduced, and also support for it.
>> >>
>> >>
>> >> There's a case for this one as well, I'll probably have it done for the fall release. But our devsrc used to pretty much be the full source it has now been pruned down to something more manageable.  There are definitely some cases for having the full source on the target again, and it will be a separate package, just not the minimal one to build out of tree modules, etc.
>> >>
>> >>
>> >>
>> >>>
>> >>>
>> >>> SDK building with such a support is good/cool. But sometimes, before
>> >>> introducing SDK, some tests should be done on target. NO need to
>> >>> optionally include built-in layer hello-world driver example. Since I
>> >>> (or you name the person) have own test drivers, which will be imported
>> >>> out of tree, externally, to the target test bed!
>> >>>
>> >>
>> >> I never use the SDK myself, so you are not alone in not going to it first. Hopefully I'll get some new patches out in the coming month before summer holidays really kick in.
>> >>
>> >> Bruce
>> >>
>> >>
>> >>>
>> >>> Just thinking loud...
>> >>>
>> >>> Zoran
>> >>> _______
>> >>>
>> >>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>> >>>>
>> >>>>
>> >>>>
>> >>>> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>> >>>>>
>> >>>>>> That's correct. That command only adds the kernel source and
>> >>>>>> build infrastructure to the SDK, not to your target image. You'd still
>> >>>>>> need to arrange to have the kernel-devsrc package installed on the
>> >>>>>> target image if you want it on the board's rootfs. How you arrange
>> >>>>>> to have the package installed to the image varies with the image
>> >>>>>> (since they all don't have the same image install variables, etc).
>> >>>>>
>> >>>>> And here is a $1,000,000 USD question? How to do it on Poky (as
>> >>>>> example of what you have stated in RED)? ;-)
>> >>>>>
>> >>>>> In other words: how to arrange it on Poky (as a Referent example)?
>> >>>>
>> >>>>
>> >>>> The core-image-kernel-dev image is how I do all my on target testing when I introduce a new reference kernel for a release. And IIRC the autobuilders are using a sato based image (Richard could confirm more easily that I could what image type the autobuilders are using for hello-world on target module tests).
>> >>>>
>> >>>> Bruce
>> >>>>
>> >>>>
>> >>>>>
>> >>>>>
>> >>>>> Thank you,
>> >>>>> Zoran
>> >>>>> _______
>> >>>>>
>> >>>>>
>> >>>>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>> >>>>>>
>> >>>>>>
>> >>>>>>
>> >>>>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>> >>>>>>>
>> >>>>>>> Hello Chris, Bruce,
>> >>>>>>>
>> >>>>>>> I have some additional data to share with you both, since I have tried
>> >>>>>>> something. And here is my take on the things!
>> >>>>>>>
>> >>>>>>>> 1. Build using a bb recipe.
>> >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>> >>>>>>>> You just need to add meta-skeleton to your bblayers.conf and then
>> >>>>>>>>   bitbake hello-mod
>> >>>>>>>
>> >>>>>>> I looked into this example, and, yes, it is classic kernel module
>> >>>>>>> definition out of the tree. With some outdated data, all cool, the
>> >>>>>>> YOCTO designer should take care himself to fix these data, if using
>> >>>>>>> this stuff.
>> >>>>>>>
>> >>>>>>> But this is NOT mandatory, since I can add out of the tree module NOT
>> >>>>>>> actually using built-in module. I just use .../tmp/deploy/images/bbb/*
>> >>>>>>> generated stuff, since I have automated scripts which are bringing all
>> >>>>>>> these on my BBB target. Then I tftp my source code module to the
>> >>>>>>> target.
>> >>>>>>>
>> >>>>>>>> 2. Build from the SDK:
>> >>>>>>>> First, add the kernel source to the SDK by adding this to conf/local.conf
>> >>>>>>>>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>> >>>>>>>
>> >>>>>>> YES, this is THE command which should generate
>> >>>>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
>> >>>>>>> local.conf and after deleting kernel, then regenerating bitbake -k
>> >>>>>>> core-image-minimal does not bring this path into the rootfs image!?
>> >>>>>>
>> >>>>>>
>> >>>>>> That's correct. That command only adds the kernel source and build infrastructure to the SDK, not to your target image. You'd still need to arrange to have the kernel-devsrc package installed on the target image if you want it on the board's rootfs. How you arrange to have the package installed to the image varies with the image (since they all don't have the same image install variables, etc).
>> >>>>>>
>> >>>>>>
>> >>>>>>>
>> >>>>>>>
>> >>>>>>> I did it actually using meta-bbb, and using poky referent distro as
>> >>>>>>> two additional layers to the more complex bbb image!
>> >>>>>>> https://github.com/jumpnow/meta-bbb.git
>> >>>>>>>
>> >>>>>>> The (KAS - you can figure out out of it local.conf) script I am using
>> >>>>>>> to build such a BBB image is here:
>> >>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>> >>>>>>>
>> >>>>>>> I did not try it with BBB reference poky only! Maybe I should try it
>> >>>>>>> as only referent poky? What do you think?
>> >>>>>>>
>> >>>>>>> Does in this case is SDK build really mandatory??? Should NOT be!
>> >>>>>>>
>> >>>>>>
>> >>>>>> You only do the SDK steps if you want to support building out of tree modules in an SDK install. So it is not mandatory for on target module builds.
>> >>>>>>
>> >>>>>> Bruce
>> >>>>>>
>> >>>>>>
>> >>>>>>>
>> >>>>>>>> Once the SDK is installed, generate the kernel headers:
>> >>>>>>>>   sudo -i
>> >>>>>>>>   . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>> >>>>>>>>   cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>> >>>>>>>>   cd /usr/src/kernel
>> >>>>>>>>   make oldconfig scripts
>> >>>>>>>>   exit
>> >>>>>>>
>> >>>>>>> This is in nutshell the same what I did (a bit different) for Embedded
>> >>>>>>> Debian. This is already on the target BBB, NOT while building YOCTO
>> >>>>>>> BBB image!
>> >>>>>>>
>> >>>>>>>> Finally, build your module using a Makefile like this
>> >>>>>>>>   obj-m := hello-mod.o
>> >>>>>>>>   all:
>> >>>>>>>>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>> >>>>>>>
>> >>>>>>> As said before: bringing my own module into the target BBB (I have my
>> >>>>>>> own examples, and I build them on the target with the almost the same
>> >>>>>>> Makefiles)
>> >>>>>>>
>> >>>>>>> Zoran
>> >>>>>>> _______
>> >>>>>>>
>> >>>>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds <chris@2net.co.uk> wrote:
>> >>>>>>>>
>> >>>>>>>> Hi Zoran,
>> >>>>>>>>
>> >>>>>>>> There are two ways to do this
>> >>>>>>>>
>> >>>>>>>> 1. Build using a bb recipe.
>> >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for an example.
>> >>>>>>>> You just need to add meta-skeleton to your bblaysers.conf and then
>> >>>>>>>>    bitbake hello-mod
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> 2. Build from the SDK:
>> >>>>>>>> First, add the kernel source to the SDK by adding this to conf/local/conf
>> >>>>>>>>    TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>> >>>>>>>>
>> >>>>>>>> Then build the SDK
>> >>>>>>>>    bitbake -c populate_sdk [your image recipe]
>> >>>>>>>>
>> >>>>>>>> Once the SDK is installed, generate the kernel headers:
>> >>>>>>>>    sudo -i
>> >>>>>>>>    . /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>> >>>>>>>>    cd /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>> >>>>>>>>    cd /usr/src/kernel
>> >>>>>>>>    make oldconfig scripts
>> >>>>>>>>    exit
>> >>>>>>>>
>> >>>>>>>> Finally, build your module using a Makefile like this
>> >>>>>>>>
>> >>>>>>>>    obj-m := hello-mod.o
>> >>>>>>>>    all:
>> >>>>>>>>          make -C $(SDKTARGETSYSROOT)/usr/src/kernel M=$(shell pwd)
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> HTH,
>> >>>>>>>> Chris
>> >>>>>>>>
>> >>>>>>>> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>> >>>>>>>>> Hello to the YOCTO community,
>> >>>>>>>>>
>> >>>>>>>>> I am using (to build the target for Beagle Bone Black) the following script:
>> >>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto
>> >>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>> >>>>>>>>>
>> >>>>>>>>> The latest kernel I am using from the following repo:
>> >>>>>>>>> https://github.com/jumpnow/meta-bbb
>> >>>>>>>>>
>> >>>>>>>>> Is kernel 5.0.14 .
>> >>>>>>>>>
>> >>>>>>>>> Here is the snippet of the boot traces:
>> >>>>>>>>> Starting kernel ...
>> >>>>>>>>>
>> >>>>>>>>> [    0.000000] Booting Linux on physical CPU 0x0
>> >>>>>>>>> [    0.000000] Linux version 5.0.14-jumpnow (oe-user@oe-host) (gcc
>> >>>>>>>>> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>> >>>>>>>>> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
>> >>>>>>>>> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing
>> >>>>>>>>> instruction cache
>> >>>>>>>>> [    0.000000] OF: fdt: Machine model: TI AM335x BeagleBone Black
>> >>>>>>>>> [    0.000000] Memory policy: Data cache writeback
>> >>>>>>>>> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>> >>>>>>>>> [    0.000000] CPU: All CPU(s) started in SVC mode.
>> >>>>>>>>> [    0.000000] AM335X ES2.1 (sgx neon)
>> >>>>>>>>> [    0.000000] random: get_random_bytes called from
>> >>>>>>>>> start_kernel+0xa4/0x460 with crng_init=0
>> >>>>>>>>> [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 130048
>> >>>>>>>>> [    0.000000] Kernel command line: console=ttyO0,115200n8
>> >>>>>>>>> root=/dev/ram0 ip=dhcp
>> >>>>>>>>>
>> >>>>>>>>> According to the documentation, the following:
>> >>>>>>>>> 2.10.1. Building Out-of-Tree Modules on the Target
>> >>>>>>>>> https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>> >>>>>>>>>
>> >>>>>>>>> I tried to find /usr/src/kernels/5.0.14... Directory, since I see
>> >>>>>>>>> from the build that kernel-dev and kernel-devsrc are included:
>> >>>>>>>>> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>> >>>>>>>>> core-image-kernel-dev                                 :1.0-r0
>> >>>>>>>>> kernel-devsrc                                         :1.0-r0
>> >>>>>>>>> kernel-selftest                                       :1.0-r0
>> >>>>>>>>>
>> >>>>>>>>> THE PROBLEM: But I could not find ob BBB target /usr/src/kernels
>> >>>>>>>>> directory at all!?
>> >>>>>>>>>
>> >>>>>>>>> Two questions here?
>> >>>>>>>>> [1] Do you have any advice on this problem (what I am missing here)?
>> >>>>>>>>> [2] Alternative to [1]: how I can use cross compiler from
>> >>>>>>>>> .../build/tmp to build Out-of-Tree Module for the BBB target on the
>> >>>>>>>>> host?
>> >>>>>>>>>
>> >>>>>>>>> Thank you,
>> >>>>>>>>> Zoran
>> >>>>>>>>> _______
>> >>>>>>>>>
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> --
>> >>>>>>>> Chris Simmonds, trainer and consultant at 2net
>> >>>>>>>> http://www.2net.co.uk
>> >>>>>>>> Author of "Mastering Embedded Linux Programming"
>> >>>>>>
>> >>>>>>
>> >>>>>>
>> >>>>>> --
>> >>>>>> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>> >>>>>> - "Use the force Harry" - Gandalf, Star Trek II
>> >>>>>>
>> >>>>
>> >>>>
>> >>>> --
>> >>>> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>> >>>> - "Use the force Harry" - Gandalf, Star Trek II
>> >>>>
>> >>
>> >>
>> >>
>> >> --
>> >> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>> >> - "Use the force Harry" - Gandalf, Star Trek II
>> >>
>
>
>
> --
> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
> - "Use the force Harry" - Gandalf, Star Trek II
>

Re: Building Out-of-Tree Modules on the BBB Target

[Bruce Ashfield]

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On Fri, May 24, 2019 at 8:50 AM Bruce Ashfield <bruce.ashfield@gmail.com>
wrote:

>
>
> On Fri, May 24, 2019 at 7:24 AM Zoran Stojsavljevic <
> zoran.stojsavljevic@gmail.com> wrote:
>
>> As I said, I am a man of experimental try-outs. And here is the try!
>>
>> Now, after setting sources, I tried to compile the example (from my Git):
>> https://github.com/ZoranStojsavljevic/bbb-yocto/tree/master/Issues/LKM
>>
>> The results are the following (all on the target):
>> root@beaglebone:~# pwd
>> /home/root
>> root@beaglebone:~# ls -al
>> drwx------    2 root     root             0 May 24 13:11 .
>> drwxr-xr-x    3 root     root             0 May 23 13:03 ..
>> -rw-r--r--    1 root     root           159 May 24 12:54 Makefile
>> -rw-r--r--    1 root     root          1228 May 24 12:54 p15_test.c
>> root@beaglebone:~# make all
>> make -C /lib/modules/5.0.15-jumpnow/build M=/home/root modules
>> make[1]: Entering directory '/lib/modules/5.0.15-jumpnow/build'
>>   CC [M]  /home/root/p15_test.o
>> In file included from ./include/asm-generic/int-ll64.h:11,
>>                  from ./arch/arm/include/uapi/asm/types.h:5,
>>                  from ./include/uapi/linux/types.h:5,
>>                  from ./include/linux/types.h:6,
>>                  from ./include/linux/list.h:5,
>>                  from ./include/linux/module.h:9,
>>                  from /home/root/p15_test.c:5:
>> *./include/uapi/asm-generic/int-ll64.h:12:10: fatal error:
>> asm/bitsperlong.h: No such file or directory*
>>  #include <asm/bitsperlong.h>
>>           ^~~~~~~~~~~~~~~~~~~
>> compilation terminated.
>>
>>
>>
>> *make[2]: *** [scripts/Makefile.build:283: /home/root/p15_test.o] Error
>> 1make[1]: *** [Makefile:1577: _module_/home/root] Error 2make[1]: Leaving
>> directory '/lib/modules/5.0.15-jumpnow/build'make: *** [Makefile:4: all]
>> Error 2*
>>
>
> I'll try some test builds and see what I can find. Some new issues may
> have crept in.
>

I can confirm that after wget'ing the files from your github, that I can
build the module just by using
kernel-devsrc (on the core-image-kernel-dev image).

I only had my qemux86-64 build handy, so I commented out the inline
assembly in the module to make sure it would build :D

Outside of that, I only ran: 'make scripts prepare' in the kernel source
dir that dev-src installed to the image.
root@qemux86-64:/tmp/f# make all
make -C /lib/modules/5.0.17-yocto-standard/build M=/tmp/f modules
make[1]: Entering directory '/lib/modules/5.0.17-yocto-standard/build'
  CC [M]  /tmp/f/p15_test.o
  Building modules, stage 2.
  MODPOST 1 modules
  CC      /tmp/f/p15_test.mod.o
  LD [M]  /tmp/f/p15_test.ko
make[1]: Leaving directory '/lib/modules/5.0.17-yocto-standard/build'

Bruce



>
> Cheers,
>
> Bruce
>
>
>
>>
>> I see that you have changed the kernel from 5.0.7-jumpnow to
>> 5.0.15-jumpnow . Did you?
>>
>> This example works on the same target out of Debian (flashed in eMMC),
>> without the problems.
>>
>> Something is wrong with the YOCTO source kernel tree.
>>
>> You are free to try example on YOCTO and Embedded Debian yourselves!
>>
>> Zoran
>> _______
>>
>> On Fri, May 24, 2019 at 6:37 AM Khem Raj <raj.khem@gmail.com> wrote:
>>
>>>
>>>
>>> On 5/23/19 9:14 PM, Zoran Stojsavljevic wrote:
>>> >  > I think this is a fair suggestion. Having prebuilt kernel available
>>> >  > that contains the configuration and header files used in the build
>>> is
>>> >  > all that is required for external modules to build in addition to
>>> >  > toolchain, so maybe its worth a try to create such a package and
>>> then
>>> >  > have kernel-source separated out which can be installed on top if
>>> one
>>> >  > needs
>>> >
>>> > I am man of experimental try-outs. So, in order to see how big kernel
>>> is,
>>> > I did the following:
>>> > Fedora 29 (which I am using as a host) with kernel-headers (NOT full
>>> > kernel source tree):
>>> > [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ pwd
>>> > /usr/src/kernels/5.0.16-200.fc29.x86_64
>>> > [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ du --summarize
>>> > /*102124    . <<======= ~95MB*/
>>> >
>>> > Kernel.org kernel 5.0.6, the full kernel source tree size:
>>> > [vuser@fedora29-ssd linux-5.0.6]$ pwd
>>> > /home/vuser/projects/kernel.org/linux-5.0.6 <
>>> http://kernel.org/linux-5.0.6>
>>> > [vuser@fedora29-ssd linux-5.0.6]$ du --summarize
>>> > /*960592    . <<======= ~900MB*/
>>> >
>>> > These are ballpark numbers. You can draw conclusions for yourselves!
>>> >
>>> > It is ~ 7x to 9x reduction in size. Having BBB's DDR2 of size 512MB,
>>> > and initramfs for testing purposes, in speaks for itself.
>>> >
>>>
>>> yes thats what I was expecting too. Anything smaller helps.
>>>
>>>
>>> > (I am aware that YOCTO kernels are less/smaller in size, but how
>>> smaller?)
>>> >
>>>
>>> Not in source. The binaries may be
>>>
>>> > Zoran
>>> > _______
>>> >
>>> >
>>> > On Fri, May 24, 2019 at 3:00 AM Khem Raj <raj.khem@gmail.com
>>> > <mailto:raj.khem@gmail.com>> wrote:
>>> >
>>> >
>>> >
>>> >     On 5/23/19 3:32 AM, Zoran Stojsavljevic wrote:
>>> >      > After some tests (and I had other problems to take care of, as
>>> well),
>>> >      > here is the following:
>>> >      >
>>> >      >> These have all been discussed off an on over the past 5 years.
>>> >      >> I can't get at bugzilla right now, but all the details are
>>> >     logged in cases.
>>> >      >> A survey of all the distros, their kernel package, etc, were
>>> all
>>> >     looked at.
>>> >      >> We had to balance the traditional packaging with some new
>>> concepts
>>> >      >> and landed with what we have now.
>>> >      >
>>> >      > I tried several tests. This is my final conclusion (two cases):
>>> >      >
>>> >
>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
>>> >      >
>>> >      > The kernel issue is described here: there is need to have the
>>> YOCTO
>>> >      > minimum configuration with the kernel setup:
>>> >      > [1] The entire kernel source code in:
>>> >      > /usr/src/kernel/`uname-r`/<kernel source code>
>>> >      > [2] The header files in: /usr/src/kernel/`uname-r`/<header file
>>> >      > directory structures>
>>> >      >
>>> >      > Point [1] is achieved with the following local.config file:
>>> >      >
>>> >
>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
>>> >      >
>>> >      > Namely, with the following snippets in the local.conf:
>>> >      > TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
>>> >      > packagegroup-core-buildessential kernel-devsrc"
>>> >      > KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
>>> >      > packagegroup-core-buildessential kernel-devsrc"
>>> >      > KERNEL_DEV_MODULE = "kernel-modules"
>>> >      > CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>>> >      > ${KERNEL_DEV_TOOLS} \
>>> >      > systemtap \
>>> >      > "
>>> >      >
>>> >      > Problem with this approach is that such a kernel makes the
>>> rootfs too
>>> >      > big and impractical:
>>> >      > -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
>>> >      > core-image-minimal-beaglebone.rootfs.tar.xz
>>> >      >
>>> >      > The main issue is point [2]: how to achieve it?
>>> >      > The suggestion is to introduce the new package in YOCTO kernel,
>>> >      > called: kernel-headers
>>> >      > The OBVIOUS benefit is that it will serve to the purpose of
>>> building
>>> >      > modules out of the tree on the target with
>>> >      > minimal mpact to rootfs!
>>> >
>>> >     I think this is a fair suggestion. Having prebuilt kernel available
>>> >     that contains the configuration and header files used in the build
>>> is
>>> >     all that is required for external modules to build in addition to
>>> >     toolchain, so maybe its worth a try to create such a package and
>>> then
>>> >     have kernel-source separated out which can be installed on top if
>>> one
>>> >     needs
>>> >
>>> >      >
>>> >      > Thank you,
>>> >      > Zoran Stojsavljevic
>>> >      > _______
>>> >      >
>>> >      > On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
>>> >      > <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>>
>>> wrote:
>>> >      >>
>>> >      >>
>>> >      >>
>>> >      >> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic
>>> >     <zoran.stojsavljevic@gmail.com
>>> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>>> >      >>>
>>> >      >>>> The core-image-kernel-dev image is how I do all my on target
>>> >      >>>> testing when I introduce a new reference kernel for a
>>> release.
>>> >      >>>
>>> >      >>> Maybe you are correct. Maybe I should use/add in my local.conf
>>> >     the following:
>>> >      >>>
>>> >      >>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
>>> >      >>> packagegroup-core-buildessential kernel-devsrc"
>>> >      >>> KERNEL_DEV_MODULE ?= "kernel-modules"
>>> >      >>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>>> >      >>>                               ${KERNEL_DEV_TOOLS} \
>>> >      >>>                               systemtap \
>>> >      >>>                              "
>>> >      >>> I need to try these... Maybe this addendum will solve the $1
>>> >     mio USD problem?!
>>> >      >>>
>>> >      >>>> And IIRC the autobuilders are using a sato based image
>>> (Richard
>>> >      >>>> could confirm more easily that I could what image type the
>>> >      >>>> autobuilders are using for hello-world on target module
>>> tests).
>>> >      >>>
>>> >      >>> I am just advertising something more simple. To have mandatory
>>> >      >>> /lib/modules/`uname -r` directory. And introduce few more
>>> >     packages, as
>>> >      >>> Fedora distro, for example, has: kernel-headers (assuming
>>> YOCTO
>>> >      >>> rootfs, the following will be installed:
>>> /usr/src/kernel/`uname
>>> >      >>> -r`/<header file directory structures>. This also makes
>>> addition of
>>> >      >>> /lib/modules/`uname -r`/build file (which is soft link to
>>> >      >>> usr/src/kernel/`uname -r`).
>>> >      >>
>>> >      >>
>>> >      >> These have all been discussed off an on over the past 5 years.
>>> I
>>> >     can't get at bugzilla right now, but all the details are logged in
>>> >     cases. A survey of all the distros, their kernel package, etc, were
>>> >     all looked at. We had to balance the traditional packaging with
>>> some
>>> >     new concepts and landed with what we have now.
>>> >      >>
>>> >      >>
>>> >      >>>
>>> >      >>> Or kernel-devel package. Then, the whole current kernel
>>> source code
>>> >      >>> will be introduced, and also support for it.
>>> >      >>
>>> >      >>
>>> >      >> There's a case for this one as well, I'll probably have it done
>>> >     for the fall release. But our devsrc used to pretty much be the
>>> full
>>> >     source it has now been pruned down to something more manageable.
>>> >     There are definitely some cases for having the full source on the
>>> >     target again, and it will be a separate package, just not the
>>> >     minimal one to build out of tree modules, etc.
>>> >      >>
>>> >      >>
>>> >      >>
>>> >      >>>
>>> >      >>>
>>> >      >>> SDK building with such a support is good/cool. But sometimes,
>>> >     before
>>> >      >>> introducing SDK, some tests should be done on target. NO need
>>> to
>>> >      >>> optionally include built-in layer hello-world driver example.
>>> >     Since I
>>> >      >>> (or you name the person) have own test drivers, which will be
>>> >     imported
>>> >      >>> out of tree, externally, to the target test bed!
>>> >      >>>
>>> >      >>
>>> >      >> I never use the SDK myself, so you are not alone in not going
>>> to
>>> >     it first. Hopefully I'll get some new patches out in the coming
>>> >     month before summer holidays really kick in.
>>> >      >>
>>> >      >> Bruce
>>> >      >>
>>> >      >>
>>> >      >>>
>>> >      >>> Just thinking loud...
>>> >      >>>
>>> >      >>> Zoran
>>> >      >>> _______
>>> >      >>>
>>> >      >>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield
>>> >     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>>
>>> wrote:
>>> >      >>>>
>>> >      >>>>
>>> >      >>>>
>>> >      >>>> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic
>>> >     <zoran.stojsavljevic@gmail.com
>>> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>>> >      >>>>>
>>> >      >>>>>> That's correct. That command only adds the kernel source
>>> and
>>> >      >>>>>> build infrastructure to the SDK, not to your target image.
>>> >     You'd still
>>> >      >>>>>> need to arrange to have the kernel-devsrc package installed
>>> >     on the
>>> >      >>>>>> target image if you want it on the board's rootfs. How you
>>> >     arrange
>>> >      >>>>>> to have the package installed to the image varies with the
>>> image
>>> >      >>>>>> (since they all don't have the same image install
>>> variables,
>>> >     etc).
>>> >      >>>>>
>>> >      >>>>> And here is a $1,000,000 USD question? How to do it on Poky
>>> (as
>>> >      >>>>> example of what you have stated in RED)? ;-)
>>> >      >>>>>
>>> >      >>>>> In other words: how to arrange it on Poky (as a Referent
>>> >     example)?
>>> >      >>>>
>>> >      >>>>
>>> >      >>>> The core-image-kernel-dev image is how I do all my on target
>>> >     testing when I introduce a new reference kernel for a release. And
>>> >     IIRC the autobuilders are using a sato based image (Richard could
>>> >     confirm more easily that I could what image type the autobuilders
>>> >     are using for hello-world on target module tests).
>>> >      >>>>
>>> >      >>>> Bruce
>>> >      >>>>
>>> >      >>>>
>>> >      >>>>>
>>> >      >>>>>
>>> >      >>>>> Thank you,
>>> >      >>>>> Zoran
>>> >      >>>>> _______
>>> >      >>>>>
>>> >      >>>>>
>>> >      >>>>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield
>>> >     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>>
>>> wrote:
>>> >      >>>>>>
>>> >      >>>>>>
>>> >      >>>>>>
>>> >      >>>>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic
>>> >     <zoran.stojsavljevic@gmail.com
>>> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>>> >      >>>>>>>
>>> >      >>>>>>> Hello Chris, Bruce,
>>> >      >>>>>>>
>>> >      >>>>>>> I have some additional data to share with you both, since
>>> I
>>> >     have tried
>>> >      >>>>>>> something. And here is my take on the things!
>>> >      >>>>>>>
>>> >      >>>>>>>> 1. Build using a bb recipe.
>>> >      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
>>> >     an example.
>>> >      >>>>>>>> You just need to add meta-skeleton to your bblayers.conf
>>> >     and then
>>> >      >>>>>>>>   bitbake hello-mod
>>> >      >>>>>>>
>>> >      >>>>>>> I looked into this example, and, yes, it is classic kernel
>>> >     module
>>> >      >>>>>>> definition out of the tree. With some outdated data, all
>>> >     cool, the
>>> >      >>>>>>> YOCTO designer should take care himself to fix these data,
>>> >     if using
>>> >      >>>>>>> this stuff.
>>> >      >>>>>>>
>>> >      >>>>>>> But this is NOT mandatory, since I can add out of the tree
>>> >     module NOT
>>> >      >>>>>>> actually using built-in module. I just use
>>> >     .../tmp/deploy/images/bbb/*
>>> >      >>>>>>> generated stuff, since I have automated scripts which are
>>> >     bringing all
>>> >      >>>>>>> these on my BBB target. Then I tftp my source code module
>>> >     to the
>>> >      >>>>>>> target.
>>> >      >>>>>>>
>>> >      >>>>>>>> 2. Build from the SDK:
>>> >      >>>>>>>> First, add the kernel source to the SDK by adding this to
>>> >     conf/local.conf
>>> >      >>>>>>>>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>> >      >>>>>>>
>>> >      >>>>>>> YES, this is THE command which should generate
>>> >      >>>>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it
>>> to
>>> >      >>>>>>> local.conf and after deleting kernel, then regenerating
>>> >     bitbake -k
>>> >      >>>>>>> core-image-minimal does not bring this path into the
>>> rootfs
>>> >     image!?
>>> >      >>>>>>
>>> >      >>>>>>
>>> >      >>>>>> That's correct. That command only adds the kernel source
>>> and
>>> >     build infrastructure to the SDK, not to your target image. You'd
>>> >     still need to arrange to have the kernel-devsrc package installed
>>> on
>>> >     the target image if you want it on the board's rootfs. How you
>>> >     arrange to have the package installed to the image varies with the
>>> >     image (since they all don't have the same image install variables,
>>> etc).
>>> >      >>>>>>
>>> >      >>>>>>
>>> >      >>>>>>>
>>> >      >>>>>>>
>>> >      >>>>>>> I did it actually using meta-bbb, and using poky referent
>>> >     distro as
>>> >      >>>>>>> two additional layers to the more complex bbb image!
>>> >      >>>>>>> https://github.com/jumpnow/meta-bbb.git
>>> >      >>>>>>>
>>> >      >>>>>>> The (KAS - you can figure out out of it local.conf) script
>>> >     I am using
>>> >      >>>>>>> to build such a BBB image is here:
>>> >      >>>>>>>
>>> >
>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>>> >      >>>>>>>
>>> >      >>>>>>> I did not try it with BBB reference poky only! Maybe I
>>> >     should try it
>>> >      >>>>>>> as only referent poky? What do you think?
>>> >      >>>>>>>
>>> >      >>>>>>> Does in this case is SDK build really mandatory??? Should
>>> >     NOT be!
>>> >      >>>>>>>
>>> >      >>>>>>
>>> >      >>>>>> You only do the SDK steps if you want to support building
>>> >     out of tree modules in an SDK install. So it is not mandatory for
>>> on
>>> >     target module builds.
>>> >      >>>>>>
>>> >      >>>>>> Bruce
>>> >      >>>>>>
>>> >      >>>>>>
>>> >      >>>>>>>
>>> >      >>>>>>>> Once the SDK is installed, generate the kernel headers:
>>> >      >>>>>>>>   sudo -i
>>> >      >>>>>>>>   .
>>> >
>>>  /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>> >      >>>>>>>>   cd
>>> >     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>> >      >>>>>>>>   cd /usr/src/kernel
>>> >      >>>>>>>>   make oldconfig scripts
>>> >      >>>>>>>>   exit
>>> >      >>>>>>>
>>> >      >>>>>>> This is in nutshell the same what I did (a bit different)
>>> >     for Embedded
>>> >      >>>>>>> Debian. This is already on the target BBB, NOT while
>>> >     building YOCTO
>>> >      >>>>>>> BBB image!
>>> >      >>>>>>>
>>> >      >>>>>>>> Finally, build your module using a Makefile like this
>>> >      >>>>>>>>   obj-m := hello-mod.o
>>> >      >>>>>>>>   all:
>>> >      >>>>>>>>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel
>>> >     M=$(shell pwd)
>>> >      >>>>>>>
>>> >      >>>>>>> As said before: bringing my own module into the target BBB
>>> >     (I have my
>>> >      >>>>>>> own examples, and I build them on the target with the
>>> >     almost the same
>>> >      >>>>>>> Makefiles)
>>> >      >>>>>>>
>>> >      >>>>>>> Zoran
>>> >      >>>>>>> _______
>>> >      >>>>>>>
>>> >      >>>>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds
>>> >     <chris@2net.co.uk <mailto:chris@2net.co.uk>> wrote:
>>> >      >>>>>>>>
>>> >      >>>>>>>> Hi Zoran,
>>> >      >>>>>>>>
>>> >      >>>>>>>> There are two ways to do this
>>> >      >>>>>>>>
>>> >      >>>>>>>> 1. Build using a bb recipe.
>>> >      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
>>> >     an example.
>>> >      >>>>>>>> You just need to add meta-skeleton to your bblaysers.conf
>>> >     and then
>>> >      >>>>>>>>    bitbake hello-mod
>>> >      >>>>>>>>
>>> >      >>>>>>>>
>>> >      >>>>>>>> 2. Build from the SDK:
>>> >      >>>>>>>> First, add the kernel source to the SDK by adding this to
>>> >     conf/local/conf
>>> >      >>>>>>>>    TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>> >      >>>>>>>>
>>> >      >>>>>>>> Then build the SDK
>>> >      >>>>>>>>    bitbake -c populate_sdk [your image recipe]
>>> >      >>>>>>>>
>>> >      >>>>>>>> Once the SDK is installed, generate the kernel headers:
>>> >      >>>>>>>>    sudo -i
>>> >      >>>>>>>>    .
>>> >
>>>  /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>> >      >>>>>>>>    cd
>>> >     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>> >      >>>>>>>>    cd /usr/src/kernel
>>> >      >>>>>>>>    make oldconfig scripts
>>> >      >>>>>>>>    exit
>>> >      >>>>>>>>
>>> >      >>>>>>>> Finally, build your module using a Makefile like this
>>> >      >>>>>>>>
>>> >      >>>>>>>>    obj-m := hello-mod.o
>>> >      >>>>>>>>    all:
>>> >      >>>>>>>>          make -C $(SDKTARGETSYSROOT)/usr/src/kernel
>>> >     M=$(shell pwd)
>>> >      >>>>>>>>
>>> >      >>>>>>>>
>>> >      >>>>>>>> HTH,
>>> >      >>>>>>>> Chris
>>> >      >>>>>>>>
>>> >      >>>>>>>> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>>> >      >>>>>>>>> Hello to the YOCTO community,
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> I am using (to build the target for Beagle Bone Black)
>>> >     the following script:
>>> >      >>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto
>>> >      >>>>>>>>>
>>> >
>>> https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> The latest kernel I am using from the following repo:
>>> >      >>>>>>>>> https://github.com/jumpnow/meta-bbb
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> Is kernel 5.0.14 .
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> Here is the snippet of the boot traces:
>>> >      >>>>>>>>> Starting kernel ...
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> [    0.000000] Booting Linux on physical CPU 0x0
>>> >      >>>>>>>>> [    0.000000] Linux version 5.0.14-jumpnow
>>> >     (oe-user@oe-host) (gcc
>>> >      >>>>>>>>> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>>> >      >>>>>>>>> [    0.000000] CPU: ARMv7 Processor [413fc082] revision
>>> 2
>>> >     (ARMv7), cr=10c5387d
>>> >      >>>>>>>>> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache,
>>> >     VIPT aliasing
>>> >      >>>>>>>>> instruction cache
>>> >      >>>>>>>>> [    0.000000] OF: fdt: Machine model: TI AM335x
>>> >     BeagleBone Black
>>> >      >>>>>>>>> [    0.000000] Memory policy: Data cache writeback
>>> >      >>>>>>>>> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>>> >      >>>>>>>>> [    0.000000] CPU: All CPU(s) started in SVC mode.
>>> >      >>>>>>>>> [    0.000000] AM335X ES2.1 (sgx neon)
>>> >      >>>>>>>>> [    0.000000] random: get_random_bytes called from
>>> >      >>>>>>>>> start_kernel+0xa4/0x460 with crng_init=0
>>> >      >>>>>>>>> [    0.000000] Built 1 zonelists, mobility grouping on.
>>> >     Total pages: 130048
>>> >      >>>>>>>>> [    0.000000] Kernel command line:
>>> console=ttyO0,115200n8
>>> >      >>>>>>>>> root=/dev/ram0 ip=dhcp
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> According to the documentation, the following:
>>> >      >>>>>>>>> 2.10.1. Building Out-of-Tree Modules on the Target
>>> >      >>>>>>>>>
>>> >
>>> https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> I tried to find /usr/src/kernels/5.0.14.
>>> >     <http://5.0.14.>.. Directory, since I see
>>> >      >>>>>>>>> from the build that kernel-dev and kernel-devsrc are
>>> >     included:
>>> >      >>>>>>>>> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>>> >      >>>>>>>>> core-image-kernel-dev
>>>  :1.0-r0
>>> >      >>>>>>>>> kernel-devsrc
>>>  :1.0-r0
>>> >      >>>>>>>>> kernel-selftest
>>>  :1.0-r0
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> THE PROBLEM: But I could not find ob BBB target
>>> >     /usr/src/kernels
>>> >      >>>>>>>>> directory at all!?
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> Two questions here?
>>> >      >>>>>>>>> [1] Do you have any advice on this problem (what I am
>>> >     missing here)?
>>> >      >>>>>>>>> [2] Alternative to [1]: how I can use cross compiler
>>> from
>>> >      >>>>>>>>> .../build/tmp to build Out-of-Tree Module for the BBB
>>> >     target on the
>>> >      >>>>>>>>> host?
>>> >      >>>>>>>>>
>>> >      >>>>>>>>> Thank you,
>>> >      >>>>>>>>> Zoran
>>> >      >>>>>>>>> _______
>>> >      >>>>>>>>>
>>> >      >>>>>>>>
>>> >      >>>>>>>>
>>> >      >>>>>>>> --
>>> >      >>>>>>>> Chris Simmonds, trainer and consultant at 2net
>>> >      >>>>>>>> http://www.2net.co.uk
>>> >      >>>>>>>> Author of "Mastering Embedded Linux Programming"
>>> >      >>>>>>
>>> >      >>>>>>
>>> >      >>>>>>
>>> >      >>>>>> --
>>> >      >>>>>> - Thou shalt not follow the NULL pointer, for chaos and
>>> >     madness await thee at its end
>>> >      >>>>>> - "Use the force Harry" - Gandalf, Star Trek II
>>> >      >>>>>>
>>> >      >>>>
>>> >      >>>>
>>> >      >>>> --
>>> >      >>>> - Thou shalt not follow the NULL pointer, for chaos and
>>> >     madness await thee at its end
>>> >      >>>> - "Use the force Harry" - Gandalf, Star Trek II
>>> >      >>>>
>>> >      >>
>>> >      >>
>>> >      >>
>>> >      >> --
>>> >      >> - Thou shalt not follow the NULL pointer, for chaos and madness
>>> >     await thee at its end
>>> >      >> - "Use the force Harry" - Gandalf, Star Trek II
>>> >      >>
>>> >
>>>
>>
>
> --
> - Thou shalt not follow the NULL pointer, for chaos and madness await thee
> at its end
> - "Use the force Harry" - Gandalf, Star Trek II
>
>

-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

[-- Attachment #2: Type: text/html, Size: 40673 bytes --]

Re: Building Out-of-Tree Modules on the BBB Target

[Zoran Stojsavljevic]

YUP! Thank you for the fix (I totally forgot about scripts directory).

Command: make scripts prepare solved it all!

Here is all captured (in order of execution):
https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/LKM/prepare_modules.log

These bugzillas will be still nice to have, Bruce, if possible (net
pointers to them).

I am acting as Scott Rifenbark, since I would like all of these
details to be rock-solid documented!

Thank you.
Zoran
_______



On Fri, May 24, 2019 at 4:16 PM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>
>
>
> On Fri, May 24, 2019 at 8:50 AM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>>
>>
>>
>> On Fri, May 24, 2019 at 7:24 AM Zoran Stojsavljevic <zoran.stojsavljevic@gmail.com> wrote:
>>>
>>> As I said, I am a man of experimental try-outs. And here is the try!
>>>
>>> Now, after setting sources, I tried to compile the example (from my Git):
>>> https://github.com/ZoranStojsavljevic/bbb-yocto/tree/master/Issues/LKM
>>>
>>> The results are the following (all on the target):
>>> root@beaglebone:~# pwd
>>> /home/root
>>> root@beaglebone:~# ls -al
>>> drwx------    2 root     root             0 May 24 13:11 .
>>> drwxr-xr-x    3 root     root             0 May 23 13:03 ..
>>> -rw-r--r--    1 root     root           159 May 24 12:54 Makefile
>>> -rw-r--r--    1 root     root          1228 May 24 12:54 p15_test.c
>>> root@beaglebone:~# make all
>>> make -C /lib/modules/5.0.15-jumpnow/build M=/home/root modules
>>> make[1]: Entering directory '/lib/modules/5.0.15-jumpnow/build'
>>>   CC [M]  /home/root/p15_test.o
>>> In file included from ./include/asm-generic/int-ll64.h:11,
>>>                  from ./arch/arm/include/uapi/asm/types.h:5,
>>>                  from ./include/uapi/linux/types.h:5,
>>>                  from ./include/linux/types.h:6,
>>>                  from ./include/linux/list.h:5,
>>>                  from ./include/linux/module.h:9,
>>>                  from /home/root/p15_test.c:5:
>>> ./include/uapi/asm-generic/int-ll64.h:12:10: fatal error: asm/bitsperlong.h: No such file or directory
>>>  #include <asm/bitsperlong.h>
>>>           ^~~~~~~~~~~~~~~~~~~
>>> compilation terminated.
>>> make[2]: *** [scripts/Makefile.build:283: /home/root/p15_test.o] Error 1
>>> make[1]: *** [Makefile:1577: _module_/home/root] Error 2
>>> make[1]: Leaving directory '/lib/modules/5.0.15-jumpnow/build'
>>> make: *** [Makefile:4: all] Error 2
>>
>>
>> I'll try some test builds and see what I can find. Some new issues may have crept in.
>
>
> I can confirm that after wget'ing the files from your github, that I can build the module just by using
> kernel-devsrc (on the core-image-kernel-dev image).
>
> I only had my qemux86-64 build handy, so I commented out the inline assembly in the module to make sure it would build :D
>
> Outside of that, I only ran: 'make scripts prepare' in the kernel source dir that dev-src installed to the image.
> root@qemux86-64:/tmp/f# make all
> make -C /lib/modules/5.0.17-yocto-standard/build M=/tmp/f modules
> make[1]: Entering directory '/lib/modules/5.0.17-yocto-standard/build'
>   CC [M]  /tmp/f/p15_test.o
>   Building modules, stage 2.
>   MODPOST 1 modules
>   CC      /tmp/f/p15_test.mod.o
>   LD [M]  /tmp/f/p15_test.ko
> make[1]: Leaving directory '/lib/modules/5.0.17-yocto-standard/build'
>
> Bruce
>
>
>>
>>
>> Cheers,
>>
>> Bruce
>>
>>
>>>
>>>
>>> I see that you have changed the kernel from 5.0.7-jumpnow to 5.0.15-jumpnow . Did you?
>>>
>>> This example works on the same target out of Debian (flashed in eMMC), without the problems.
>>>
>>> Something is wrong with the YOCTO source kernel tree.
>>>
>>> You are free to try example on YOCTO and Embedded Debian yourselves!
>>>
>>> Zoran
>>> _______
>>>
>>> On Fri, May 24, 2019 at 6:37 AM Khem Raj <raj.khem@gmail.com> wrote:
>>>>
>>>>
>>>>
>>>> On 5/23/19 9:14 PM, Zoran Stojsavljevic wrote:
>>>> >  > I think this is a fair suggestion. Having prebuilt kernel available
>>>> >  > that contains the configuration and header files used in the build is
>>>> >  > all that is required for external modules to build in addition to
>>>> >  > toolchain, so maybe its worth a try to create such a package and then
>>>> >  > have kernel-source separated out which can be installed on top if one
>>>> >  > needs
>>>> >
>>>> > I am man of experimental try-outs. So, in order to see how big kernel is,
>>>> > I did the following:
>>>> > Fedora 29 (which I am using as a host) with kernel-headers (NOT full
>>>> > kernel source tree):
>>>> > [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ pwd
>>>> > /usr/src/kernels/5.0.16-200.fc29.x86_64
>>>> > [vuser@fedora29-ssd 5.0.16-200.fc29.x86_64]$ du --summarize
>>>> > /*102124    . <<======= ~95MB*/
>>>> >
>>>> > Kernel.org kernel 5.0.6, the full kernel source tree size:
>>>> > [vuser@fedora29-ssd linux-5.0.6]$ pwd
>>>> > /home/vuser/projects/kernel.org/linux-5.0.6 <http://kernel.org/linux-5.0.6>
>>>> > [vuser@fedora29-ssd linux-5.0.6]$ du --summarize
>>>> > /*960592    . <<======= ~900MB*/
>>>> >
>>>> > These are ballpark numbers. You can draw conclusions for yourselves!
>>>> >
>>>> > It is ~ 7x to 9x reduction in size. Having BBB's DDR2 of size 512MB,
>>>> > and initramfs for testing purposes, in speaks for itself.
>>>> >
>>>>
>>>> yes thats what I was expecting too. Anything smaller helps.
>>>>
>>>>
>>>> > (I am aware that YOCTO kernels are less/smaller in size, but how smaller?)
>>>> >
>>>>
>>>> Not in source. The binaries may be
>>>>
>>>> > Zoran
>>>> > _______
>>>> >
>>>> >
>>>> > On Fri, May 24, 2019 at 3:00 AM Khem Raj <raj.khem@gmail.com
>>>> > <mailto:raj.khem@gmail.com>> wrote:
>>>> >
>>>> >
>>>> >
>>>> >     On 5/23/19 3:32 AM, Zoran Stojsavljevic wrote:
>>>> >      > After some tests (and I had other problems to take care of, as well),
>>>> >      > here is the following:
>>>> >      >
>>>> >      >> These have all been discussed off an on over the past 5 years.
>>>> >      >> I can't get at bugzilla right now, but all the details are
>>>> >     logged in cases.
>>>> >      >> A survey of all the distros, their kernel package, etc, were all
>>>> >     looked at.
>>>> >      >> We had to balance the traditional packaging with some new concepts
>>>> >      >> and landed with what we have now.
>>>> >      >
>>>> >      > I tried several tests. This is my final conclusion (two cases):
>>>> >      >
>>>> >     https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/kernel-development.txt
>>>> >      >
>>>> >      > The kernel issue is described here: there is need to have the YOCTO
>>>> >      > minimum configuration with the kernel setup:
>>>> >      > [1] The entire kernel source code in:
>>>> >      > /usr/src/kernel/`uname-r`/<kernel source code>
>>>> >      > [2] The header files in: /usr/src/kernel/`uname-r`/<header file
>>>> >      > directory structures>
>>>> >      >
>>>> >      > Point [1] is achieved with the following local.config file:
>>>> >      >
>>>> >     https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/Issues/local-devsrc.conf
>>>> >      >
>>>> >      > Namely, with the following snippets in the local.conf:
>>>> >      > TOOLCHAIN_TARGET_TASK_append = " packagegroup-core-tools-profile
>>>> >      > packagegroup-core-buildessential kernel-devsrc"
>>>> >      > KERNEL_DEV_TOOLS = "packagegroup-core-tools-profile
>>>> >      > packagegroup-core-buildessential kernel-devsrc"
>>>> >      > KERNEL_DEV_MODULE = "kernel-modules"
>>>> >      > CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>>>> >      > ${KERNEL_DEV_TOOLS} \
>>>> >      > systemtap \
>>>> >      > "
>>>> >      >
>>>> >      > Problem with this approach is that such a kernel makes the rootfs too
>>>> >      > big and impractical:
>>>> >      > -rw-r--r--. 2 user vboxusers 101499952 May 17 14:32
>>>> >      > core-image-minimal-beaglebone.rootfs.tar.xz
>>>> >      >
>>>> >      > The main issue is point [2]: how to achieve it?
>>>> >      > The suggestion is to introduce the new package in YOCTO kernel,
>>>> >      > called: kernel-headers
>>>> >      > The OBVIOUS benefit is that it will serve to the purpose of building
>>>> >      > modules out of the tree on the target with
>>>> >      > minimal mpact to rootfs!
>>>> >
>>>> >     I think this is a fair suggestion. Having prebuilt kernel available
>>>> >     that contains the configuration and header files used in the build is
>>>> >     all that is required for external modules to build in addition to
>>>> >     toolchain, so maybe its worth a try to create such a package and then
>>>> >     have kernel-source separated out which can be installed on top if one
>>>> >     needs
>>>> >
>>>> >      >
>>>> >      > Thank you,
>>>> >      > Zoran Stojsavljevic
>>>> >      > _______
>>>> >      >
>>>> >      > On Thu, May 16, 2019 at 12:04 AM Bruce Ashfield
>>>> >      > <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
>>>> >      >>
>>>> >      >>
>>>> >      >>
>>>> >      >> On Wed, May 15, 2019 at 4:09 PM Zoran Stojsavljevic
>>>> >     <zoran.stojsavljevic@gmail.com
>>>> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>>>> >      >>>
>>>> >      >>>> The core-image-kernel-dev image is how I do all my on target
>>>> >      >>>> testing when I introduce a new reference kernel for a release.
>>>> >      >>>
>>>> >      >>> Maybe you are correct. Maybe I should use/add in my local.conf
>>>> >     the following:
>>>> >      >>>
>>>> >      >>> KERNEL_DEV_TOOLS ?= "packagegroup-core-tools-profile
>>>> >      >>> packagegroup-core-buildessential kernel-devsrc"
>>>> >      >>> KERNEL_DEV_MODULE ?= "kernel-modules"
>>>> >      >>> CORE_IMAGE_EXTRA_INSTALL += "${KERNEL_DEV_MODULE} \
>>>> >      >>>                               ${KERNEL_DEV_TOOLS} \
>>>> >      >>>                               systemtap \
>>>> >      >>>                              "
>>>> >      >>> I need to try these... Maybe this addendum will solve the $1
>>>> >     mio USD problem?!
>>>> >      >>>
>>>> >      >>>> And IIRC the autobuilders are using a sato based image (Richard
>>>> >      >>>> could confirm more easily that I could what image type the
>>>> >      >>>> autobuilders are using for hello-world on target module tests).
>>>> >      >>>
>>>> >      >>> I am just advertising something more simple. To have mandatory
>>>> >      >>> /lib/modules/`uname -r` directory. And introduce few more
>>>> >     packages, as
>>>> >      >>> Fedora distro, for example, has: kernel-headers (assuming YOCTO
>>>> >      >>> rootfs, the following will be installed: /usr/src/kernel/`uname
>>>> >      >>> -r`/<header file directory structures>. This also makes addition of
>>>> >      >>> /lib/modules/`uname -r`/build file (which is soft link to
>>>> >      >>> usr/src/kernel/`uname -r`).
>>>> >      >>
>>>> >      >>
>>>> >      >> These have all been discussed off an on over the past 5 years. I
>>>> >     can't get at bugzilla right now, but all the details are logged in
>>>> >     cases. A survey of all the distros, their kernel package, etc, were
>>>> >     all looked at. We had to balance the traditional packaging with some
>>>> >     new concepts and landed with what we have now.
>>>> >      >>
>>>> >      >>
>>>> >      >>>
>>>> >      >>> Or kernel-devel package. Then, the whole current kernel source code
>>>> >      >>> will be introduced, and also support for it.
>>>> >      >>
>>>> >      >>
>>>> >      >> There's a case for this one as well, I'll probably have it done
>>>> >     for the fall release. But our devsrc used to pretty much be the full
>>>> >     source it has now been pruned down to something more manageable.
>>>> >     There are definitely some cases for having the full source on the
>>>> >     target again, and it will be a separate package, just not the
>>>> >     minimal one to build out of tree modules, etc.
>>>> >      >>
>>>> >      >>
>>>> >      >>
>>>> >      >>>
>>>> >      >>>
>>>> >      >>> SDK building with such a support is good/cool. But sometimes,
>>>> >     before
>>>> >      >>> introducing SDK, some tests should be done on target. NO need to
>>>> >      >>> optionally include built-in layer hello-world driver example.
>>>> >     Since I
>>>> >      >>> (or you name the person) have own test drivers, which will be
>>>> >     imported
>>>> >      >>> out of tree, externally, to the target test bed!
>>>> >      >>>
>>>> >      >>
>>>> >      >> I never use the SDK myself, so you are not alone in not going to
>>>> >     it first. Hopefully I'll get some new patches out in the coming
>>>> >     month before summer holidays really kick in.
>>>> >      >>
>>>> >      >> Bruce
>>>> >      >>
>>>> >      >>
>>>> >      >>>
>>>> >      >>> Just thinking loud...
>>>> >      >>>
>>>> >      >>> Zoran
>>>> >      >>> _______
>>>> >      >>>
>>>> >      >>> On Wed, May 15, 2019 at 4:25 PM Bruce Ashfield
>>>> >     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
>>>> >      >>>>
>>>> >      >>>>
>>>> >      >>>>
>>>> >      >>>> On Wed, May 15, 2019 at 3:44 AM Zoran Stojsavljevic
>>>> >     <zoran.stojsavljevic@gmail.com
>>>> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>>>> >      >>>>>
>>>> >      >>>>>> That's correct. That command only adds the kernel source and
>>>> >      >>>>>> build infrastructure to the SDK, not to your target image.
>>>> >     You'd still
>>>> >      >>>>>> need to arrange to have the kernel-devsrc package installed
>>>> >     on the
>>>> >      >>>>>> target image if you want it on the board's rootfs. How you
>>>> >     arrange
>>>> >      >>>>>> to have the package installed to the image varies with the image
>>>> >      >>>>>> (since they all don't have the same image install variables,
>>>> >     etc).
>>>> >      >>>>>
>>>> >      >>>>> And here is a $1,000,000 USD question? How to do it on Poky (as
>>>> >      >>>>> example of what you have stated in RED)? ;-)
>>>> >      >>>>>
>>>> >      >>>>> In other words: how to arrange it on Poky (as a Referent
>>>> >     example)?
>>>> >      >>>>
>>>> >      >>>>
>>>> >      >>>> The core-image-kernel-dev image is how I do all my on target
>>>> >     testing when I introduce a new reference kernel for a release. And
>>>> >     IIRC the autobuilders are using a sato based image (Richard could
>>>> >     confirm more easily that I could what image type the autobuilders
>>>> >     are using for hello-world on target module tests).
>>>> >      >>>>
>>>> >      >>>> Bruce
>>>> >      >>>>
>>>> >      >>>>
>>>> >      >>>>>
>>>> >      >>>>>
>>>> >      >>>>> Thank you,
>>>> >      >>>>> Zoran
>>>> >      >>>>> _______
>>>> >      >>>>>
>>>> >      >>>>>
>>>> >      >>>>> On Wed, May 15, 2019 at 7:41 AM Bruce Ashfield
>>>> >     <bruce.ashfield@gmail.com <mailto:bruce.ashfield@gmail.com>> wrote:
>>>> >      >>>>>>
>>>> >      >>>>>>
>>>> >      >>>>>>
>>>> >      >>>>>> On Tue, May 14, 2019 at 1:30 PM Zoran Stojsavljevic
>>>> >     <zoran.stojsavljevic@gmail.com
>>>> >     <mailto:zoran.stojsavljevic@gmail.com>> wrote:
>>>> >      >>>>>>>
>>>> >      >>>>>>> Hello Chris, Bruce,
>>>> >      >>>>>>>
>>>> >      >>>>>>> I have some additional data to share with you both, since I
>>>> >     have tried
>>>> >      >>>>>>> something. And here is my take on the things!
>>>> >      >>>>>>>
>>>> >      >>>>>>>> 1. Build using a bb recipe.
>>>> >      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
>>>> >     an example.
>>>> >      >>>>>>>> You just need to add meta-skeleton to your bblayers.conf
>>>> >     and then
>>>> >      >>>>>>>>   bitbake hello-mod
>>>> >      >>>>>>>
>>>> >      >>>>>>> I looked into this example, and, yes, it is classic kernel
>>>> >     module
>>>> >      >>>>>>> definition out of the tree. With some outdated data, all
>>>> >     cool, the
>>>> >      >>>>>>> YOCTO designer should take care himself to fix these data,
>>>> >     if using
>>>> >      >>>>>>> this stuff.
>>>> >      >>>>>>>
>>>> >      >>>>>>> But this is NOT mandatory, since I can add out of the tree
>>>> >     module NOT
>>>> >      >>>>>>> actually using built-in module. I just use
>>>> >     .../tmp/deploy/images/bbb/*
>>>> >      >>>>>>> generated stuff, since I have automated scripts which are
>>>> >     bringing all
>>>> >      >>>>>>> these on my BBB target. Then I tftp my source code module
>>>> >     to the
>>>> >      >>>>>>> target.
>>>> >      >>>>>>>
>>>> >      >>>>>>>> 2. Build from the SDK:
>>>> >      >>>>>>>> First, add the kernel source to the SDK by adding this to
>>>> >     conf/local.conf
>>>> >      >>>>>>>>   TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>>> >      >>>>>>>
>>>> >      >>>>>>> YES, this is THE command which should generate
>>>> >      >>>>>>> /usr/src/kernel(s)/`uname -r` or similar... But adding it to
>>>> >      >>>>>>> local.conf and after deleting kernel, then regenerating
>>>> >     bitbake -k
>>>> >      >>>>>>> core-image-minimal does not bring this path into the rootfs
>>>> >     image!?
>>>> >      >>>>>>
>>>> >      >>>>>>
>>>> >      >>>>>> That's correct. That command only adds the kernel source and
>>>> >     build infrastructure to the SDK, not to your target image. You'd
>>>> >     still need to arrange to have the kernel-devsrc package installed on
>>>> >     the target image if you want it on the board's rootfs. How you
>>>> >     arrange to have the package installed to the image varies with the
>>>> >     image (since they all don't have the same image install variables, etc).
>>>> >      >>>>>>
>>>> >      >>>>>>
>>>> >      >>>>>>>
>>>> >      >>>>>>>
>>>> >      >>>>>>> I did it actually using meta-bbb, and using poky referent
>>>> >     distro as
>>>> >      >>>>>>> two additional layers to the more complex bbb image!
>>>> >      >>>>>>> https://github.com/jumpnow/meta-bbb.git
>>>> >      >>>>>>>
>>>> >      >>>>>>> The (KAS - you can figure out out of it local.conf) script
>>>> >     I am using
>>>> >      >>>>>>> to build such a BBB image is here:
>>>> >      >>>>>>>
>>>> >     https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-releases/bbb-warrior/kas-bbb-warrior.yml
>>>> >      >>>>>>>
>>>> >      >>>>>>> I did not try it with BBB reference poky only! Maybe I
>>>> >     should try it
>>>> >      >>>>>>> as only referent poky? What do you think?
>>>> >      >>>>>>>
>>>> >      >>>>>>> Does in this case is SDK build really mandatory??? Should
>>>> >     NOT be!
>>>> >      >>>>>>>
>>>> >      >>>>>>
>>>> >      >>>>>> You only do the SDK steps if you want to support building
>>>> >     out of tree modules in an SDK install. So it is not mandatory for on
>>>> >     target module builds.
>>>> >      >>>>>>
>>>> >      >>>>>> Bruce
>>>> >      >>>>>>
>>>> >      >>>>>>
>>>> >      >>>>>>>
>>>> >      >>>>>>>> Once the SDK is installed, generate the kernel headers:
>>>> >      >>>>>>>>   sudo -i
>>>> >      >>>>>>>>   .
>>>> >     /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>>> >      >>>>>>>>   cd
>>>> >     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>>> >      >>>>>>>>   cd /usr/src/kernel
>>>> >      >>>>>>>>   make oldconfig scripts
>>>> >      >>>>>>>>   exit
>>>> >      >>>>>>>
>>>> >      >>>>>>> This is in nutshell the same what I did (a bit different)
>>>> >     for Embedded
>>>> >      >>>>>>> Debian. This is already on the target BBB, NOT while
>>>> >     building YOCTO
>>>> >      >>>>>>> BBB image!
>>>> >      >>>>>>>
>>>> >      >>>>>>>> Finally, build your module using a Makefile like this
>>>> >      >>>>>>>>   obj-m := hello-mod.o
>>>> >      >>>>>>>>   all:
>>>> >      >>>>>>>>         make -C $(SDKTARGETSYSROOT)/usr/src/kernel
>>>> >     M=$(shell pwd)
>>>> >      >>>>>>>
>>>> >      >>>>>>> As said before: bringing my own module into the target BBB
>>>> >     (I have my
>>>> >      >>>>>>> own examples, and I build them on the target with the
>>>> >     almost the same
>>>> >      >>>>>>> Makefiles)
>>>> >      >>>>>>>
>>>> >      >>>>>>> Zoran
>>>> >      >>>>>>> _______
>>>> >      >>>>>>>
>>>> >      >>>>>>> On Sun, May 12, 2019 at 3:15 PM Chris Simmonds
>>>> >     <chris@2net.co.uk <mailto:chris@2net.co.uk>> wrote:
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> Hi Zoran,
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> There are two ways to do this
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> 1. Build using a bb recipe.
>>>> >      >>>>>>>> Take a look at meta-skeleton/recipes-kernel/hello-mod for
>>>> >     an example.
>>>> >      >>>>>>>> You just need to add meta-skeleton to your bblaysers.conf
>>>> >     and then
>>>> >      >>>>>>>>    bitbake hello-mod
>>>> >      >>>>>>>>
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> 2. Build from the SDK:
>>>> >      >>>>>>>> First, add the kernel source to the SDK by adding this to
>>>> >     conf/local/conf
>>>> >      >>>>>>>>    TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> Then build the SDK
>>>> >      >>>>>>>>    bitbake -c populate_sdk [your image recipe]
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> Once the SDK is installed, generate the kernel headers:
>>>> >      >>>>>>>>    sudo -i
>>>> >      >>>>>>>>    .
>>>> >     /opt/poky/2.6.2/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
>>>> >      >>>>>>>>    cd
>>>> >     /opt/poky/2.6.2/sysroots/cortexa8hf-neon-poky-linux-gnueabi
>>>> >      >>>>>>>>    cd /usr/src/kernel
>>>> >      >>>>>>>>    make oldconfig scripts
>>>> >      >>>>>>>>    exit
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> Finally, build your module using a Makefile like this
>>>> >      >>>>>>>>
>>>> >      >>>>>>>>    obj-m := hello-mod.o
>>>> >      >>>>>>>>    all:
>>>> >      >>>>>>>>          make -C $(SDKTARGETSYSROOT)/usr/src/kernel
>>>> >     M=$(shell pwd)
>>>> >      >>>>>>>>
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> HTH,
>>>> >      >>>>>>>> Chris
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> On 12/05/2019 11:53, Zoran Stojsavljevic wrote:
>>>> >      >>>>>>>>> Hello to the YOCTO community,
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> I am using (to build the target for Beagle Bone Black)
>>>> >     the following script:
>>>> >      >>>>>>>>> https://github.com/ZoranStojsavljevic/bbb-yocto
>>>> >      >>>>>>>>>
>>>> >     https://github.com/ZoranStojsavljevic/bbb-yocto/blob/master/bbb-yocto.sh
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> The latest kernel I am using from the following repo:
>>>> >      >>>>>>>>> https://github.com/jumpnow/meta-bbb
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> Is kernel 5.0.14 .
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> Here is the snippet of the boot traces:
>>>> >      >>>>>>>>> Starting kernel ...
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> [    0.000000] Booting Linux on physical CPU 0x0
>>>> >      >>>>>>>>> [    0.000000] Linux version 5.0.14-jumpnow
>>>> >     (oe-user@oe-host) (gcc
>>>> >      >>>>>>>>> version 8.3.0 (GCC)) #1 Fri May 10 13:12:33 UTC 2019
>>>> >      >>>>>>>>> [    0.000000] CPU: ARMv7 Processor [413fc082] revision 2
>>>> >     (ARMv7), cr=10c5387d
>>>> >      >>>>>>>>> [    0.000000] CPU: PIPT / VIPT nonaliasing data cache,
>>>> >     VIPT aliasing
>>>> >      >>>>>>>>> instruction cache
>>>> >      >>>>>>>>> [    0.000000] OF: fdt: Machine model: TI AM335x
>>>> >     BeagleBone Black
>>>> >      >>>>>>>>> [    0.000000] Memory policy: Data cache writeback
>>>> >      >>>>>>>>> [    0.000000] cma: Reserved 16 MiB at 0x9f000000
>>>> >      >>>>>>>>> [    0.000000] CPU: All CPU(s) started in SVC mode.
>>>> >      >>>>>>>>> [    0.000000] AM335X ES2.1 (sgx neon)
>>>> >      >>>>>>>>> [    0.000000] random: get_random_bytes called from
>>>> >      >>>>>>>>> start_kernel+0xa4/0x460 with crng_init=0
>>>> >      >>>>>>>>> [    0.000000] Built 1 zonelists, mobility grouping on.
>>>> >     Total pages: 130048
>>>> >      >>>>>>>>> [    0.000000] Kernel command line: console=ttyO0,115200n8
>>>> >      >>>>>>>>> root=/dev/ram0 ip=dhcp
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> According to the documentation, the following:
>>>> >      >>>>>>>>> 2.10.1. Building Out-of-Tree Modules on the Target
>>>> >      >>>>>>>>>
>>>> >     https://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> I tried to find /usr/src/kernels/5.0.14.
>>>> >     <http://5.0.14.>.. Directory, since I see
>>>> >      >>>>>>>>> from the build that kernel-dev and kernel-devsrc are
>>>> >     included:
>>>> >      >>>>>>>>> [user@fedora29-ssd bbb-yocto]$ bitbake -s | grep kernel
>>>> >      >>>>>>>>> core-image-kernel-dev                                 :1.0-r0
>>>> >      >>>>>>>>> kernel-devsrc                                         :1.0-r0
>>>> >      >>>>>>>>> kernel-selftest                                       :1.0-r0
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> THE PROBLEM: But I could not find ob BBB target
>>>> >     /usr/src/kernels
>>>> >      >>>>>>>>> directory at all!?
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> Two questions here?
>>>> >      >>>>>>>>> [1] Do you have any advice on this problem (what I am
>>>> >     missing here)?
>>>> >      >>>>>>>>> [2] Alternative to [1]: how I can use cross compiler from
>>>> >      >>>>>>>>> .../build/tmp to build Out-of-Tree Module for the BBB
>>>> >     target on the
>>>> >      >>>>>>>>> host?
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>> Thank you,
>>>> >      >>>>>>>>> Zoran
>>>> >      >>>>>>>>> _______
>>>> >      >>>>>>>>>
>>>> >      >>>>>>>>
>>>> >      >>>>>>>>
>>>> >      >>>>>>>> --
>>>> >      >>>>>>>> Chris Simmonds, trainer and consultant at 2net
>>>> >      >>>>>>>> http://www.2net.co.uk
>>>> >      >>>>>>>> Author of "Mastering Embedded Linux Programming"
>>>> >      >>>>>>
>>>> >      >>>>>>
>>>> >      >>>>>>
>>>> >      >>>>>> --
>>>> >      >>>>>> - Thou shalt not follow the NULL pointer, for chaos and
>>>> >     madness await thee at its end
>>>> >      >>>>>> - "Use the force Harry" - Gandalf, Star Trek II
>>>> >      >>>>>>
>>>> >      >>>>
>>>> >      >>>>
>>>> >      >>>> --
>>>> >      >>>> - Thou shalt not follow the NULL pointer, for chaos and
>>>> >     madness await thee at its end
>>>> >      >>>> - "Use the force Harry" - Gandalf, Star Trek II
>>>> >      >>>>
>>>> >      >>
>>>> >      >>
>>>> >      >>
>>>> >      >> --
>>>> >      >> - Thou shalt not follow the NULL pointer, for chaos and madness
>>>> >     await thee at its end
>>>> >      >> - "Use the force Harry" - Gandalf, Star Trek II
>>>> >      >>
>>>> >
>>
>>
>>
>> --
>> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
>> - "Use the force Harry" - Gandalf, Star Trek II
>>
>
>
> --
> - Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end
> - "Use the force Harry" - Gandalf, Star Trek II
>